U.S. patent application number 10/519147 was filed with the patent office on 2005-11-17 for sampling kits, devices and uses thereof.
Invention is credited to Devonshire, Martin Adrian, Poku, Ernest, Sanchez-Felix, Manuel Vicente.
Application Number | 20050252820 10/519147 |
Document ID | / |
Family ID | 9939516 |
Filed Date | 2005-11-17 |
United States Patent
Application |
20050252820 |
Kind Code |
A1 |
Sanchez-Felix, Manuel Vicente ;
et al. |
November 17, 2005 |
Sampling kits, devices and uses thereof
Abstract
Disclosed are sampling kits and sampling devices and uses of the
same. A sampling kit is disclosed including a swab (10) with a
handle (12) and a swab head (14). The kit also includes a container
(30) with an optional closure (70). Sampling head (14) is
detachable from the handle (12) by engaging the sampling head with
engagement means and moving the handle with respect to the
engagement means. The engagement means may be formed on the closure
or on the container. After detachment of the sampling head from the
handle, the sampling head remains in the container. The container
may then be sealed using sealing means (220). Also disclosed is a
sampling kit containing processing means for initiating sample
processing of sample collected. The processing means disclosed is
an absorbent cover means (88) which allows sample held by the
sampling head to transfer to the cover means. In particular, the
adsorbent material may be an impregnated paper which is capable of
yielding amplifiable nucleic acid from buccal cells.
Inventors: |
Sanchez-Felix, Manuel Vicente;
(Zionsville, IN) ; Devonshire, Martin Adrian;
(Portsmouth, GB) ; Poku, Ernest; (London,
GB) |
Correspondence
Address: |
NIXON & VANDERHYE, PC
901 NORTH GLEBE ROAD, 11TH FLOOR
ARLINGTON
VA
22203
US
|
Family ID: |
9939516 |
Appl. No.: |
10/519147 |
Filed: |
December 27, 2004 |
PCT Filed: |
June 27, 2003 |
PCT NO: |
PCT/GB03/02800 |
Current U.S.
Class: |
206/569 |
Current CPC
Class: |
A61B 10/0045 20130101;
A61B 10/0051 20130101; A61B 10/0096 20130101; A61B 10/02
20130101 |
Class at
Publication: |
206/569 |
International
Class: |
B65D 069/00; B65D
071/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 28, 2002 |
GB |
0215044.9 |
Claims
1. A sampling kit having: a sampling device with a sampling head
and a handle; a container for receiving the sampling head; and,
optionally, a closure for closing an open end off the container,
wherein the container or closure has engagement means arranged so
that the sampling head is detachable from the handle by engaging
the sampling head with the engagement means and moving the handle
with respect to the engagement means.
2. A sampling kit according to claim 1, wherein, in the sampling
device, the handle has a distal end and a proximal end, the
proximal end being for handling by a user and the sampling head
being detachably supported around a support portion at the distal
end of the handle.
3. A sampling kit according to claim 2 wherein the sampling head is
connected to the support portion by at least one frangible
connection extending therebetween.
4. A sampling kit according to claim 2 wherein the sampling head is
at least partially hollow so that, before the sampling head is
detached from the handle, there is a space suitable for sample
retention between an internal surface of the sampling head and a
surface of the support portion.
5. A sampling kit according to claim 1 wherein the sampling head is
formed so that, in use, once detached from the handle, it presents
an aperture.
6. A sampling kit according to claim 5 wherein, in use, the
aperture becomes enlarged compared to the cross-sectional area of
the handle during detachment of the sampling head from the
handle.
7. A sampling kit according to claim 1 wherein the sampling head is
splittable into two or more segments, thereby allowing exposure for
analysis of sampled material held inside the sampling head.
8. A sampling kit according to claim 7 wherein, in use, the
segments of the sampling head which split apart abut the inner
surface of the container.
9. A sampling kit according to claim 1 wherein the sampling head is
formed of a material which substantially does not absorb DNA and/or
water.
10. A sampling kit according to claim 1 wherein the engagement
means is formed at a surface of the closure.
11. A sampling kit according to claim 10 wherein the engagement
means has a tapering shape to assist, in use, detachment and/or
segmentation of the sampling head.
12. A sampling kit according to claim 10 wherein the handle of the
sampling device is slidable within the closure, to enable
detachment of the sampling head by the engagement means.
13. A sampling kit according to claim 12 wherein the closure
includes an aperture in which the handle of the sampling device is
slidable the aperture being closable substantially to seal the
closure when the handle is removed from the closure.
14. A sampling kit according to claim 10 wherein the closure
includes an adapter and sealing means shaped to cooperate with the
adapter substantially to seal the adapter.
15. A sampling kit according to claim 14 wherein the adapter is
connectable to the container at the open end of the container.
16. A sampling kit according to claim 14 wherein the engagement
means is formed at a surface of the adapter.
17. A sampling kit according to claim 16 wherein the engagement
means is an aperture through the adapter, shaped to allow the
sampling head through the adapter in a first rotational position
and to prevent the sampling head passing through the adapter in a
second rotational position.
18. A sampling kit according to claim 14 wherein the sampling head
is detachable from the handle via relative rotational movement
between the engagement means and the sampling head.
19. A sampling kit according to claim 14 wherein the sealing means
is attachable to the container via attachment means independent of
the cap.
20. A sampling kit according to claim 1 wherein the engagement
means is formed on an internal surface of the container.
21. A sampling kit according to claim 20 wherein the engagement
means is a lip, step, barb or slot formed on the internal surface
of the container and shaped and/or directed to allow the sampling
head to pass into the container in an entry direction, but not in
an exit direction, to detach the sampling head from the handle.
22. A sampling kit according to claim 21 wherein the engagement
means comprises a tapering internal cross-section of the
container.
23. A sampling kit according to claim 1 wherein the container is
suitable for multiple well testing, such as part of a 24, 32, 48,
96, 384 or 1536 well plate or is suitable for use in such a well
plate or microplate.
24. Use of a sampling kit according to claim 1 to take a biological
sample from a subject or location, with the optional further steps
of storing and/or processing the sample.
25. Use off a sampling device to take a biological sample from a
subject, the sampling device having a handle and a detachable
sampling head, the use including the step of engaging the sampling
head with engagement means of a container or of an associated
closure and moving the handle with respect to the engagement means
to detach the sampling head from the handle, with the optional
further steps of storing and/or processing the sample.
26. A use according to claim 24 wherein the sampling head is
detached from the handle by manipulating the handle to force the
sampling head against the engagement means and, optionally,
subsequently removing the handle.
27. A use according to claim 26 wherein the sampling head is
rotated from a first, entry rotational position to a second,
detachment configuration, relative to the engagement means, before
detachment of the sampling head from the handle.
28. A use according to claim 26 wherein the sampling head deforms
during engagement with the engagement means, thereby breaking a
connection between the sampling head and the handle.
29. A use according to claim 28 wherein subsequent movement of the
handle with respect to the sampling head causes the sampling head
to split or partially split into segments.
30. A use according to claim 23 wherein detachment of the sampling
head from the handle occurs during withdrawal of the handle from
the container, engaging the sampling head on the engagement
means.
31. A use according to any one of claim 23 wherein detachment of
the sampling head from the handle occurs during entry of the
sampling device into the container.
32. A use according to claim 23 wherein the detachment of the
sampling head from the handle occurs via movement of the sampling
device substantially along a principal axis of the container.
33. A sampling kit according to claim 23 further including
processing means for initiating sample processing of sample
collected, the processing means being locatable in the
container.
34. A sampling kit having: a sampling device with a sampling head
and a handle; a container for receiving the sampling head;
processing means for initiating sample processing of sample
collected, and, optionally, a closure for closing an open end of
the container, wherein the processing means is locatable in the
container.
35. A sampling kit according to claim 33 or claim 34 wherein the
processing means is an absorbent cover means to allow, in use,
sample held by the sampling head to transfer to the cover
means.
36. A sampling kit according to claim 35 wherein the absorbent
material is an impregnated paper or fabric which is capable of
yielding amplifiable nucleic acid from suitable biological
material, such as buccal cells.
37. A sampling kit according to claim 35 wherein the absorbent
covering means is configurable to be interposed between the
sampling head and an inner surface of the container.
38. A sampling kit according to claim 33 wherein the processing
means is capable of initiating or performing cell lysing on sample
held, in use, in the container.
39. Use of a sampling kit according to claim 33 to take a
biological sample from a subject or location, with the optional
further steps of storing and/or processing the sample.
40. A use according to claim 24 further including the step of
carrying out at least one of a DNA/RNA assay, forensics, chemical,
biological, microbiological sampling, or cleaning validation of
process equipment to be used for pharmaceuticals, foods, proteins
or biological species.
Description
[0001] The present invention relates to sampling kits and sampling
devices. In particular, it relates to swab kits for taking and
analysing biological samples.
[0002] Biological samples can be used to obtain and analyse DNA.
DNA is usually extracted from such samples using known DNA
purification techniques. The aim of such techniques is typically to
produce a preparation of DNA roughly 40-150 Kb in length,
representing the genetic information within a cell.
[0003] Modern DNA isolation techniques exploit both the physical
and chemical properties of DNA molecules. Cell lysis and protein
denaturisation is accomplished simultaneously using proteolytic
enzymes, chemical denaturants and heat. DNA can be separated and
purified by sorting out (Miller et al, 1998, Nucleic Acids
Research, Vol. 16, page 1215) or by reversing binding to a matrix.
Modern isolation techniques can allow isolation and purification of
DNA in a relatively short time, e.g. 20-30 minutes.
[0004] In order to carry out DNA testing on biological material
from a subject, it is first necessary to obtain a sample of the
biological material. For some types of cells, it is easier to
extract DNA than other types of cells. Furthermore, some types of
cells are more easily sampled from a subject than others. For DNA
analysis, buccal (cheek) cells are often sampled from a subject
since they yield DNA relatively easily and they are easy to
obtain.
[0005] To obtain buccal cells from a subject (e.g. patient or
client), a swab is typically used. Typically, the swab is
self-administered by the subject. Typical swabs have a handle and a
swab head (here also referred to as "sampling head"). The swab head
is brushed over the inside surface of the subject's cheek to scrape
away some buccal cells. Subsequently, the swab is stored in a
container for storage before analysis can be carried out. A
particular advantage of buccal cell samples is that such samples
can be transported safely by mail. Furthermore, they can be stored
for lengthy periods of time whilst still yielding high quality DNA
after storage.
[0006] Known swabs include: swab TS/19-M of Technical Service
Consultants Ltd.; IsoSwab.TM. (Ref: ISO-SWAB) of Schleicher &
Schuell Inc.; Catch-All.TM. Sample Collection Swab of Epicentre,
Madison Wis. 53713 USA; and the foam-tipped applicator of Whatman
International Ltd., Maidstone, Kent ME16 OLS, UK.
[0007] The main product on the market for buccal cell sampling has
been the Omniswab.TM. of Whatman International Ltd. (catalogue
number WB10-0004). This swab has a tubular handle with a serrated
swab head mounted at a slit in a first end. A plunger extends
through the length of the handle and away from the second end of
the handle. A user can depress the plunger to remove the swab head
from the handle. Therefore, after sampling, the swab head can be
removed from the handle without the user touching the swab head.
This can help to avoid contamination of the sample with other
samples or with other external contaminants.
[0008] A problem with the Whatman Omniswab.TM. is that the nature
of the swab head detachment system requires that only a narrow
surface area of the swab head is available to rub against the cheek
for capture of buccal cells. Therefore, although the swab provides
a mechanism for detachment of the swab head from the handle, the
yield of biological material from the swab head is often
unsatisfactory. This problem is exacerbated by the fact that the
swab head is made from absorbent material. This material typically
swells during processes to isolate DNA from the buccal cells and
the material also absorbs DNA. This reduces yet further the yield
of DNA from the swab head.
[0009] A first development of the present invention has several
aspects, which are discussed below. In general, the first
development uses engagement means associated with a container into
which the head is to be received, or associated with a closure of
the container, to detach a sampling head. This can reduce the risk
of contamination and also allows the number of processing steps
involved with sampling and/or analysis of the sample to be
reduced.
[0010] Preferably, in a first aspect, the first development of the
present invention provides: a sampling kit having a sampling device
with a sampling head and a handle; a container for receiving the
sampling head; and, optionally, a closure for closing an open end
of the container, wherein the container or closure has engagement
means arranged so that the sampling head is detachable from the
handle by engaging the sampling head with the engagement means and
moving the handle with respect to the engagement means.
[0011] In this first aspect, the sampling head may be removed from
the handle in a way which reduces the risk of contamination from a
user, in particular by simplifying the construction of the
handle.
[0012] Preferably, in a second aspect, the present invention
provides a use of a sampling kit according to the first aspect to
take a biological sample from a subject or location, with the
optional further steps of storing and/or processing the sample.
[0013] In a third aspect of the first development, the present
invention preferably provides a use (or a method of operation) of a
sampling device to take a biological sample from a subject, the
sampling device having a handle and a detachable sampling head, the
use including the step of engaging the sampling head with
engagement means of a container or of an associated closure and
moving the handle with respect to the engagement means to detach
the sampling head from the handle, with the optional further steps
of storing and/or processing the sample.
[0014] In this way, the detached sampling head can be separated
from the handle so that the sampling head can be located in the
container without the handle.
[0015] Preferably, the sampling device of the third aspect is part
of the sampling kit of the first aspect. The optional or preferred
features which follow may be applied to any or all of the first,
second or third aspects.
[0016] Preferably, in the sampling device, the handle has a distal
end and a proximal end. Typically, the proximal end is for handling
by a user. Preferably, the sampling head is detachably supported
around a support portion at the distal end of the handle. In this
way, the sampling head may embrace the support portion of the
distal end of the handle.
[0017] Preferably, the sampling head is connected to the support
portion by at least one frangible connection extending
therebetween. Breakage of said at least one frangible connection
can allow the detachment of the sampling head from the support
portion.
[0018] The sampling head may be at least partially hollow. This can
have the advantageous effect that, before the sampling head is
detached from the handle, there is a space suitable for sample
retention between an internal surface of the sampling head and a
surface of the support portion.
[0019] The sampling head may be formed so that, in use, once
detached from the handle, it presents an aperture. Preferably, in
use, the aperture becomes enlarged compared to the cross-sectional
area of the handle during detachment of the sampling head from the
handle. Furthermore, the sampling head preferably is splittable
into two or more segments, thereby allowing exposure for analysis
of sampled material held inside the sampling head. In use, the
segments of the sampling head which split apart may abut the inner
surface of the container. This has the advantage that the segments
of the sampling head can be disposed away from the central axis of
the container, so that they do not impede the subsequent insertion
of probes into the container to carry out processes on the
sample.
[0020] Preferably, the sampling head is formed of a material which
substantially does not absorb DNA and/or water. Thus, the sampling
head material can allow a large proportion of the sample collected
to be available for subsequent processing.
[0021] As mentioned above, the sampling head may be attached to the
support portion of the handle via one or more releasable
attachments. Such attachments may be re-attachable. However, since
the sampling kit is typically manufactured for single use
applications (e.g. supplied sterile or clinically clean for
biological material sampling), the sampling head is typically
attached to the support portion by one or more breakable
attachments. In particular, the head may be attached to the handle
via a series of breakable links extending from the end portion of
the shaft to the sampling head.
[0022] In the case where the sampling head is hollow, the breakable
links connecting the handle to the sampling head typically extend
from the support portion to the internal surface of the sampling
head. A particular advantage associated with a hollow sampling head
is that some biological material to be sampled can be held within
the head. This can help to improve the sampling efficiency of the
sampling kit.
[0023] A further advantage associated with a hollow sampling head
is that a retention volume, in which biological material can be
disadvantageously retained during an isolation procedure subsequent
to a sampling step, is advantageously reduced in comparison to a
non-hollow sampling head of similar outer dimensions. This is
particularly the case if the sampling head is capable of being
split to allow access to biological material held within the
sampling head. This advantage can be enhanced by using a material
for the sampling head which does not absorb water and/or DNA
material. The yield of DNA material from the sampling head can
consequently be increased.
[0024] Preferably, the sampling head has an undulating outer
surface. This can improve the material collecting efficiency of the
sampling head, particularly when the material to be collected is in
part abraded from its source. Typical surface configurations
include ribbed, toothed, bobbled, dimpled, etc. For some
applications, a smooth outer surface of the sampling head is
suitable. A smooth outer surface may be useful for sampling from
people with sensitive mouths or for sampling from open wounds.
Furthermore, a smooth outer surface may be useful for cleaning
validation of process equipment used for the manufacture of drugs
or chemicals or biological or fluid products. The material of the
sample head may be selected to provide a gentle surface
texture.
[0025] An advantage of forming the sampling head of a material
which does not absorb DNA or water is that this allows the yield of
DNA to be improved by substantially avoiding absorption of DNA by
the sampling head material. Similarly, if the sampling head
material does not absorb water, aqueous solutions or buffers can be
more easily recovered from processes subsequent to the sampling
step. Consequently, the sampling head can be left in the container
during the subsequent processing steps. Avoiding the need to remove
the sampling head from the container avoids yet another step by
which the contents of the container could become contaminated.
[0026] The material of the sampling head may be a semi-rigid
plastics material, such as suitably processed polypropylene, e.g.
melt-blown (typically 100% melt-blown) polypropylene. Other
materials suitable for the sampling head include polyethylene, PBT
(polybutylene tetraphalate), nylon 6, nylon 11, polycarbonate,
poly(4-5 methylpentene-1), polystyrene and polyethylene
terephthalate. Typically, such material will be formed by melt
blowing. In this sense, any polymer suitable for melt blowing can
be used to form the sampling head. The fibres of the sampling head
typically have a round cross-section. However, square, rectangular,
triangular, pie segment and cross-shaped fibres may be used. Such
angular fibres can affect the surface texture of the sampling head.
For this reason, such materials may allow a further increase in the
yield of biological material from the sampling head.
[0027] Preferred sampling devices have sampling heads formed using
polypropylene, e.g. melt blown polypropylene. The average fibre
diameter in the sampling head may be 1 .mu.m or more, preferably 5
.mu.m or more. The average fibre diameter in the sampling head may
be 20 .mu.m or less, preferably 10 .mu.m or less.
[0028] In a preferred embodiment, the engagement means is formed at
a surface of the closure. This allows the engagement means to be
formed separately from the container, allowing the use of readily
available containers of a standard size.
[0029] The engagement means may have a tapering shape to assist, in
use, detachment and/or segmentation of the sampling head. The
tapering shape preferably tapers in cross-sectional area in a
direction along the principal axis of the container, when the
closure is fitted on the container. The engagement means may be,
for example, convex or concave. If convex, the engagement means may
taper to increase the cross-sectional area of the engagement means
in the direction of movement of the handle to remove the sampling
head. In this way, the sampling head can be prised from the handle,
for example by a wedging action. If convex, the surface of the
engagement means is preferably conical or frusto-conical. If
concave, the engagement means may taper to decrease the bore area
of the engagement means in the direction of movement of the handle
to remove the sampling head. In this way, the sampling head can be
squeezed from the handle. The engagement means may be a suitably
shaped slot in the closure.
[0030] Preferably, the handle of the sampling device is slidable
within the closure, to enable detachment of the sampling head by
the engagement means. The closure may be separable from the
container.
[0031] In use, the assembly of the closure and sampling device may
be mounted on the container by inserting the sampling head and part
of the handle into the container and attaching the closure to the
container. Subsequent withdrawal of the handle from the container
through the closure may cause detachment of the sampling head.
[0032] The closure may include an aperture in which the handle of
the sampling device is slidable, the aperture being closable
substantially to seal the closure when the handle is removed from
the closure.
[0033] Preferably, the closure includes an adapter such as a cap
and sealing means shaped to cooperate with the adapter
substantially to seal the adapter. The adapter may be connectable
to the container at the open end of the container. The aperture may
be formed through the adapter. The engagement means may be formed
on a surface of the adapter.
[0034] Preferably, the engagement means is an aperture through the
adapter, shaped (e.g. as an elongate slot) to allow the sampling
head through the adapter in a first rotational position and to
prevent the sampling head passing through the adapter in a second
rotational position. Thus, detachment of the sampling head may be
achieved in the second rotational position. In this way, the
sampling kit may include a cap which is connectable to the
container, the cap having engagement means allowing detachment of
the sampling head from the handle. Thus, the container may be a
container of a standard form and the cap may be fixable to the
container, for example by means of a cooperating screw thread, by
adhesive or by welding (e.g. ultrasonic welding).
[0035] Preferably, the sealing means is attachable to the container
via attachment means independent of the cap. In this way, the
sealing means may be attached to the container independently from
the cap, for example to ensure that the sealing means is not lost
during use of the kit. The attachment means may include a resilient
ring attachable around the container. The ring may be attached to
the sealing means by a resilient link. The sealing means may be a
plug shaped to cooperate with an opening in the cap. The function
of the sealing means is typically to seal the cap to ensure that
sample is not lost from the container, for example through the
aperture of the closure through which the handle is slidable.
[0036] In another embodiment, the engagement means is formed on an
internal surface of the container. In that case, the kit may not
include a closure.
[0037] The container may be a tube which is closed at one end and
open at the other end to receive the sampling head.
[0038] The engagement means may, for example, be a lip, step, barb
or slot formed on the internal surface of the container and shaped
and/or directed to allow the sampling head to pass into the
container in an entry direction, but not in an exit direction, to
detach the sampling head from the handle. Using this arrangement,
the sampling head can be trapped in the container as it is detached
from the handle.
[0039] Additionally or alternatively, the engagement means may
comprise a tapering internal cross-section of the container. The
internal surfaces of the container may be shaped, for example, so
that the distance between opposing internal surfaces of the
container changes with distance along the container. In the case
where the container is tubular, the change in cross-section of the
container may be gradual along at least a part of the axial length
of the container. In particular, an internal cross-section
dimension of the container may reduce with depth from the open end
of the container. Preferably, the internal sectional shape of the
container is equilateral, e.g. square, circular, hexagonal, etc.
Advantageously, the internal cross-sectional area of the container
may also correspondingly change with depth. With this arrangement,
the sampling head may be inserted into the container until it is
jammed between opposing internal surfaces of the container. Further
insertion of the handle into the container may then detach the
sampling head from the handle, following which the handle can be
removed from the container.
[0040] Additionally or alternatively, the container may have a
flexible portion, for example one or more flexible walls. In that
case, the engagement means may be the internal surfaces of said
flexible walls. A user can detach the sampling head from the handle
by inserting the sampling head into the container and holding the
sampling head with respect to the container by pressing or
squeezing the sampling head by pressing or squeezing an appropriate
part of the container, and then moving the handle to detach the
sampling head.
[0041] The container is typically of a standard size and shape. In
particular, the container is preferably the same container as used
for further processing of the sample collected by the sampling kit.
Such further processing may include an assay such as an analysis of
the sample collected by chemical, biological, biochemical,
forensic, etc. testing or testing involving the clean validation of
process equipment used for the manufacture of drugs or chemicals or
biological or food products. It is often advantageous to carry out
such testing using automated equipment for the introduction of
reagents and the subsequent analysis of the product(s). Such
automated equipment has the advantage of reliability,
reproducibility and standardisation, sample identification
tracking, along with a smaller risk of contamination, over
conventional non-automated analysis. Furthermore, automated
equipment can run very many similar tests at the same time,
reducing the overall time required for carrying out a large number
of tests. However, such automated equipment is also expensive, and
so is usually designed according to a standard. In the field of
assays such as high throughput screening and/or DNA assays, the
standard has become the use of multi-well plates, i.e. an array of
individual reaction containers set out in a predetermined shape,
order and geometry with particular dimensions. In particular, the
use of 96-well plates or microplates has become commonplace, with
each plate having an 8.times.12 rectangular array of reaction
containers. The plate may either be moulded in one piece, including
the containers, or the containers may be separable from a holder
having an array of corresponding housings. Higher density well
plates are also known for similar applications, e.g. 384
(16.times.24 array) and 1536 (32.times.48 array). Alternatively,
24, 32 or 48 well plates may be used, the container being suitable
for at least one of such plates.
[0042] In a preferred embodiment, a rack allowing an array of up to
32 containers is envisaged. For such containers, the volume of the
containers may be at least 0.1 ml, about 0.25 ml or up to 2 or 2.5
ml, and/or at most 4 or 3.5 ml.
[0043] The sampling kit may be used for applications other than DNA
assays. In particular, the sampling kit may be used for protein
assays and/or for cleaning validation of process equipment to be
used in the manufacture of drug products/substances or other
pharmaceuticals, foods processing/products, chemicals or biological
processing/products.
[0044] Preferably, therefore, the container used in the sampling
kit is compatible for use in standardised automated assay
equipment. In particular, the container is shaped and dimensioned
to be suitable for multi-well (e.g. 32-well or 96-well) testing.
The container may be an individual container, or it may be attached
to other (typically similar) container in an array suitable for a
multi-well (e.g. 32-well or 96-well) assay.
[0045] Typically, the container has an internal depth of at least
10 mm. Preferably the depth is at least 30 mm. Typically the
container has an internal depth of at most 200 mm, preferably at
most 80 mm.
[0046] Typically, the container has an internal width at its open
end of at least 4 mm, preferably at least 6 mm. Typically, the
container has an internal width at its open end of at most 15 mm,
preferably at most 11 mm.
[0047] Overall, the container typically has a volume of about 1.2
ml, but volumes of 0.25, 0.5, 0.8 and 2 ml (and others in this
range) may also be used. As mentioned above, use of containers with
volumes larger than this is also envisaged.
[0048] The containers preferably have a rounded internal
cross-sectional shape. However, it is possible for the containers
to have an angular, e.g. rectangular cross-sectional shape.
[0049] The sampling device may also be adapted to be more suited to
automated assay techniques. The sampling head may be formed so
that, once detached from the handle, it presents an aperture. The
aperture may be formed at that part of the sampling head though
which the handle extends before the sampling head is detached from
the handle. Therefore, the aperture may take the shape of the
handle at that part of the sampling device. As mentioned above, the
sampling head is preferably hollow, so that it may hold sampled
material. The aperture typically allows access to the sampled
material held within the sampling head. The aperture is therefore
preferably of a suitable size and shape to allow access to the
interior of the sampling head to, e.g., reagents and/or probes.
[0050] The aperture may be of a different size and shape to the
size and shape of the handle. In particular, the aperture may
become enlarged compared to the cross-sectional area of the handle
during the detachment process. Dilatation of the aperture may be
achieved by respective sides of the sampling head splitting apart.
In the intact sampling device, the sampling head may be formed in
different, e.g. longitudinal, segments which are connected along
lines of weakness. Subsequent detachment of the sampling head from
the handle may cause the segments to break apart, for example
around the aperture, thereby dilating the aperture. In some cases,
the sampling head may split into two or more parts, thereby
exposing sampled material for analysis. In preferred embodiments,
the parts of the sampling head which split apart abut the inner
surface of the container. This can leave the central, e.g. axial,
portion of the container free of sampling head, which may allow a
probe (e.g. an automated probe) more easily to enter the container.
Furthermore, this feature may reduce the risk of a probe
accidentally withdrawing the sampling head from the container,
which otherwise could lead to cross-contamination of other
containers.
[0051] The sampling head may be non-symmetrical. In particular, it
may have a first width measured in one direction which is greater
than a second width measured in another direction. Put another way,
the sampling head may have a flattened configuration. This is
particularly applicable where the engagement means of the container
for detaching the sampling head is the tapering walls of the
container or closure. In that case, the sampling head may be
detached from the handle by pressing the sampling device, head
first, into the container. At the part of the container at which
the first width is the same as the internal width of the container,
the sampling head touches opposing internal surfaces of the
container. Further insertion of the sampling head into the
container may cause the sampling head to deform, thereby breaking a
connection between the sampling head and the handle. The
deformation may cause the sampling head to split or partially split
into segments. Once the sampling head and handle are no longer
connected, further insertion of the handle into the container may
assist in splitting the sampling head apart. Removal of the handle
back through the sampling head may further separate the segments of
the sampling head. The configuration of the remains of the
breakable connections between the handle and the sampling head may
assist in this. Alternatively, where the engagement means is formed
on the closure, the sampling head may be detached when the handle
is drawn away from the container, the detachment process otherwise
taking a similar form.
[0052] In the case where the engaging means of the container is a
discontinuity such as a step, lip or barb on the internal surface
of the container, the change in internal diameter (or internal
width) of the container at the discontinuity should usually be at
least about 2 mm. Alternatively, the internal width at the
narrowest part of the container around the discontinuity should be
at least about 2 mm smaller than the width (e.g. the largest width)
of the sampling head. In this case, the detachment of the sampling
head from the handle typically comes when the sampling device is
being removed from the container, catching the sampling head on the
discontinuity. Further removal of the handle typically breaks the
connection between the sampling head and the handle. The shape of
the handle and/or the shape of the broken connection between the
handle and the sampling head may be chosen to allow the sampling
head to be split apart (either partially or wholly) as the handle
is further extracted from the container.
[0053] In some cases where the engaging means of the container is a
surface of the closure, asymmetry of the sampling head can be less
important, in a similar way to the case where the engaging means is
a discontinuity on the internal surface of the container. In these
cases, the sampling head is typically detached from the handle by
being forced against the engagement means. Again, the sampling head
may be split apart by interaction between the broken connecting
elements attached to the handle. The shape of the engagement means
also has a role to play. In particular, the engagement means may
have a tapering shape extending into the container (e.g. a wedge
shape or a frusto-conical shape) when the closure is attached to
the container. Then the sampling head may be split apart (either
wholly or partially) by being forced along the tapering shape of
the engagement means as the handle is withdrawn from the
container.
[0054] It is mentioned here that the term "closure" is intended to
include a lid, stopper, cap or bung or other equivalent closing
means.
[0055] The engagement means may be formed by an extension or
attachment of the closure. In particular, when the closure is in
place closing the container, the engagement means, although
connected to the closure, may be located some distance away from
the opening end of the container. The closure may have an extended
neck portion which extends into the container, towards the closed
end of the container. Preferably, when the lid is in place closing
the container, the neck portion extends at least 50%, or preferably
at least 75% along the longitudinal axis of the container, towards
the closed end (e.g. the base) of the container. Having the
engagement means relatively close to the base of the container
allows the sampling head to be detached from the handle at a
location relatively close to the base of the container. In this
way, the sampling head is less likely to become stuck between the
walls of the container at a location away from the base of the
container.
[0056] The extended neck may include guide means. This guide means
may cooperate with corresponding means (e.g. a groove, ridge or
lug) formed on the handle. The guide means preferably extends along
a predetermined portion of the neck, from the engagement means. In
operation, an end of the guide means away from the engagement means
may provide a stop limit for movement of the handle with respect to
the next. Preferably, this stop limit allows the swab head to be
detached from the handle by the engagement means before the stop
limit is reached. After detachment of the sampling head from the
handle, the handle and lid may be removed from the container
together, e.g. by pulling the handle. The cooperation of the stop
limit of the guide means and the handle can thereby allow removal
of the lid and handle in a single operation. This may, for example,
be done robotically, e.g. prior to DNA isolation processing.
[0057] Preferably, the sampling head is formed of a material which
is sufficiently rigid to allow the sampling head to split open
during (or after) detachment of the sampling head from the handle
by the engagement means. Suitable materials are mentioned above.
The rigidity of the sampling head is determined by its shape and by
the material used. The rigidity also determines (in part) the
abrasiveness of the sample head, to obtain high yields of
cells/DNA. Typically, the sampling head material is selected so
that the sampling head is substantially not capable of absorbing
water or DNA.
[0058] The sampling head is preferably formed in two segments.
These segments are typically of similar size and shape. They are
typically formed as one piece, with one or more lines of weakness
joining them, or they are formed as separate pieces which are
subsequently bonded together (the bonds forming lines of weakness).
During detachment from the handle, the segments preferably split
apart.
[0059] The sampling head is preferably joined to the handle by a
series of breakable attachment elements. These may be attachment
fingers or lattices. Preferably, these elements break at their
connection with the sampling head. In this way, once the sampling
head is detached from the handle, the connection elements remain
attached to the handle and are removable from the container with
the handle. In order to assist with breaking open the sampling head
on removal of the handle, the connection elements are typically
protruding elements. They may, for example, protrude from the
handle to a width as great at the width of the sampling head, or
slightly smaller. They may provide the sampling head with rigidity,
particularly where the sampling head has a flattened configuration.
They may be attached to the sampling head at a line of weakness,
e.g. at a join between segments of the sampling head.
[0060] Usually, the dimensions of the sampling head are chosen with
respect to the container which will be used with the sampling
device. For multi-well applications in particular, the length of
the sampling head may be about 10-20 mm, preferably about 17 mm.
The width in one direction may be about 5-8 mm, preferably about 7
mm. The width in another direction may be about 2-5 mm, preferably
about 3-3.5 mm.
[0061] An important factor in assessing the risk of contamination
of a sample is the number of steps taken during the lifetime of the
sample. The steps include the taking and storage of the sample, but
also include subsequent processing steps and/or assay of the
sample.
[0062] The inventors have realised that the number of processing
steps required to be undertaken during use of the sampling kit can
be reduced by incorporating processing means into the kit.
[0063] Accordingly, in an independent, second development of the
invention there is provided a preferred first aspect, providing a
sampling kit having: a sampling device with a sampling head and a
handle; a container for receiving the sampling head; processing
means for initiating sample processing of sample collected, and,
optionally, a closure for closing an open end of the container,
wherein the processing means is locatable or located in the
container.
[0064] In a second preferred aspect of the second development,
there is provided a sampling kit according to the first aspect of
the first development, further including processing means for
initiating sample processing of sample collected, the processing
means being locatable or located in the container.
[0065] In the first or the second aspect, the inclusion of
processing means into the kit allows a later processing step to be
avoided. Typically, each processing step requires invasion of the
sample held in the container. Thus, the reduction in processing
steps reduces the chances of contamination of the sample.
[0066] In a third preferred aspect of the second development, there
is provided a use of a sampling kit according to the first or
second aspect of the second development to take a biological sample
from a subject or location, with the optional further steps of
storing and/or processing the sample.
[0067] Preferably, the third aspect further includes the step of
carrying out at least one of a DNA/RNA assay, forensics, chemical,
biological, microbiological sampling, or cleaning validation of
process equipment to be used for pharmaceuticals, foods, proteins
or biological species.
[0068] Preferred and/or optional features of the first, second or
third development are mentioned below. Any aspect or optional
feature of the second development may be combined with any aspect
or optional feature of the first development.
[0069] Preferably, the processing means is capable of initiating or
performing cell lysing on sample held, in use, in the
container.
[0070] Handling of a fluid sample can be simplified by allowing the
sample to be absorbed into an absorbent material such as filter
paper. Subsequent drying of the paper can allow retention of useful
biological material in or on the paper. Typically, this can be
handled more easily than the original fluid sample, e.g. parts of
the paper can be cut away for further analysis by rehydration of
the sample.
[0071] However, the transfer of sample to the filter paper is
inefficient, since it is difficult to ensure that a usefully large
proportion of the sample held by, e.g., a swab is transferred to
the filter paper by wiping the swab on the paper.
[0072] To address this, preferably, the processing means is as
absorbent cover means to allow, in use, sample held by the sampling
head to transfer to the cover means. The absorbent material may be
an impregnated paper or fabric which is capable of yielding
amplifiable nucleic acid from suitable biological material, such as
buccal cells.
[0073] The absorbent covering means may be configurable to be
interposed between the sampling head and an inner surface of the
container. This can allow efficient transfer of sample from the
sampling head to the absorbent covering means.
[0074] Preferably, in use, there is included the step of
transferring sample from the sampling head to the absorbent
material by receiving the sampling head in the cover means formed
of the absorbent material.
[0075] The absorbent cover means may be a sheet of absorbent
material configured to define a shape which is able to cooperate
with the shape of the sampling head. In particular, the cover means
may be shaped to enclose or embrace (at least partially but
preferably wholly) the sampling head. The cover means may be a
sleeve, collar or tube and may be open or closed.
[0076] Absorbent material is known which can not only help in the
storage of biological samples, but which also can initiate
processing of the sample. An example of such material is
IsoCode.TM. paper, available from Schleicher & Schuell (P.O.
Box 4, D-37582 Dassel, Germany). Preferred embodiments of the
present invention incorporate similar material. Accordingly, the
cover means is preferably formed from a material which is capable
of interacting with biological material to release nucleic
acid(s).
[0077] The biological material may be cellular material or virus
particles, for example.
[0078] The interaction between the biological material and suitable
material for the cover means may be a disrupting or lysing
interaction for cellular material or a disrupting interaction for
virus particles. Typically, the kit is to be used for assays of
double stranded DNA (dsDNA), as found in nucleated cells, but is
also suitable for other DNA such as ssDNA or other nucleic acids
such as RNA (e.g. ssRNA, dsRNA, tRNA or rRNA), mitochondrial DNA,
plasmid/bacterial DNA samples, etc.
[0079] In general, the absorbent material is preferably an
impregnated (or otherwise treated) paper or fabric which is capable
of yielding amplifiable nucleic acid from suitable biological
material, such as buccal cells.
[0080] The absorbent covering means is preferably configurable to
be interposed between the sampling head and an inner surface of the
container. Preferably, in use, the covering means is pressed
between the sampling head and the inner surface of the
container.
[0081] In the kit, before use, the cover means may be disposed in
the container, i.e. prior to the sample head being received by the
cover means. In that case, the cover means may be a lining (e.g. a
partial lining) of the container. An advantage of having the cover
means pre-placed in the container of the kit is that the user does
not need to perform this step. This eliminates a step from the
sampling process and so reduces the risk of contamination.
[0082] Alternatively, before use, the container and the cover means
may be separate. In that case, the use may include the step of
locating the cover means in the container. This step may take place
before or after the sampling head is received by the cover
means.
[0083] Preferably, the kit or use is according to the first
development of the invention, with absorbent cover means provided
which is configurable to be interposed between the sampling head
and an internal surface of the container. Typically, this allows an
efficient transfer of sample held by the sampling head to the cover
means.
[0084] Preferred embodiments of the invention will now be
described, by way of example only, with reference to the
accompanying drawings, in which:
[0085] FIG. 1 is a schematic longitudinal cross-sectional view of a
kit according to an embodiment of the invention.
[0086] FIG. 2 is a schematic lateral cross-sectional view along
line A-A' in FIG. 1.
[0087] FIG. 3 is a schematic longitudinal cross-sectional view of
the kit of FIG. 1 with the swab further inserted.
[0088] FIG. 4 is a schematic lateral cross-sectional view along
line B-B' in FIG. 3.
[0089] FIG. 5 is a schematic longitudinal cross-sectional view of
the kit of FIG. 3 with the swab still further inserted.
[0090] FIG. 6 is a schematic lateral cross-sectional view along
line C-C' in FIG. 5.
[0091] FIG. 7 is a schematic longitudinal cross-sectional view of
the kit of FIG. 5 with the handle of the swab being removed from
the container.
[0092] FIG. 8 is a schematic lateral cross-sectional view along
line D-D' in FIG. 7.
[0093] FIG. 9 is a schematic longitudinal cross-sectional view of a
container for use in a kit according to an embodiment of the
present invention.
[0094] FIG. 10 is a schematic longitudinal cross-sectional view of
an alternative container for use in a kit according to an
embodiment of the present invention.
[0095] FIG. 11 is a schematic longitudinal cross-sectional view of
a kit according to an embodiment of the invention.
[0096] FIG. 12 is a schematic longitudinal cross-sectional view of
a kit according to another embodiment of the invention.
[0097] FIG. 13 is a schematic longitudinal cross-sectional view of
an alternative stopper for use with the kit shown in FIG. 12.
[0098] FIG. 14 is a schematic lateral cross-sectional view along
line E-E' in FIG. 13.
[0099] FIG. 15 is a schematic longitudinal cross-sectional view of
another alternative stopper for use with the kit shown in FIG.
12.
[0100] FIG. 1-6 is a schematic lateral cross-sectional view along
line F-F' in FIG. 15.
[0101] FIG. 17 is an enlarged, schematic, exploded view of one end
of a swab for use in or with embodiments of the invention.
[0102] FIG. 18 is an enlarged, schematic, exploded view of one end
of another swab for use in or with embodiments of the
invention.
[0103] FIG. 19 is an enlarged, schematic, exploded view of one end
of a further swab for use in or with embodiments of the
invention.
[0104] FIG. 20 is an enlarged, schematic, exploded view of one end
of a further swab for use in or with embodiments of the
invention.
[0105] FIG. 21 is a schematic, exploded, partial longitudinal
cross-section of a kit according to an embodiment of the
invention.
[0106] FIG. 22 is a schematic longitudinal cross-section of part of
a kit according to another embodiment of the invention.
[0107] FIG. 23 is a schematic longitudinal cross-section of a kit
according to another embodiment of the invention.
[0108] FIG. 24 shows the kit of FIG. 23 with the stopper in place
closing the container.
[0109] FIG. 25 shows the kit of FIGS. 23 and 24 after detachment of
the sampling head from the swab handle.
[0110] FIG. 26 is a schematic longitudinal cross-section of a kit
according to an alternative embodiment of the invention.
[0111] FIG. 27 shows the kit of FIG. 26 with the stopper in place
closing the container.
[0112] FIG. 28 shows the kit of FIGS. 26 and 27 during removal of
the stopper and swab handle from the container.
[0113] FIG. 29 shows a schematic view of the stopper only, along
line G-G' in FIG. 27.
[0114] FIG. 30 is a schematic longitudinal cross-section of a kit
according to another embodiment of the invention, without the
swab.
[0115] FIG. 31 is a schematic lateral cross-sectional view along
line H-H' in FIG. 30.
[0116] FIG. 32 is a schematic longitudinal cross-sectional view of
the kit of FIG. 30 with the swab inserted in a first rotational
position.
[0117] FIG. 33 is a schematic longitudinal cross-sectional view of
the kit of FIG. 30 with the swab in the second (head detachment)
rotation position.
[0118] FIG. 34 is a schematic longitudinal cross-sectional view of
the kit of FIG. 30 with the swab head detached, the swab handle
removed and the stopper lid sealing the adapter.
[0119] FIG. 35 is a schematic longitudinal cross-sectional view of
a kit according to another embodiment of the invention.
[0120] FIG. 36 is a schematic longitudinal cross-sectional view of
the kit of FIG. 35 with the swab head detached, the handle removed
and the cap sealing the container.
[0121] FIGS. 1 to 8 illustrate a mode of operation of a kit
according to an embodiment of the invention. Like features are
given the same reference numerals in these drawings.
[0122] FIG. 1 shows one end of a swab 10, including a shaft 12 at
one end of which is formed a swab head 14. Such a swab is
illustrated in more detail in FIG. 17. In FIG. 17, there is shown
an enlarged exploded view of the structure of the swab 10. The
shaft 12 narrows to a constriction 16 which leads to a flattened
tongue portion 18. Connection elements 20 project from the narrow
sides of tongue portion 18. The swab head 14 is composed of two
opposing segments 14a and 14b. Segments 14a and 14b are lightly
bonded to each other at their peripheries, embracing the tongue 18.
Connection elements 20 provide some extra stiffness to the
structure and may be sandwiched in the bond between the segments
14a and 14b. The upper ends 22a and 22b of the segments 14a and 14b
form a collar around the constriction 18 and may be lightly bonded
to the surface of the constriction 18. There is a hollow space
between the inside surfaces of the segments 22a,22b and the tongue
18.
[0123] Swab head 14 is made from melt blown polypropylene,
typically 100% melt blown polypropylene. The surface of the swab
head 14 is ridged. This allows the swab to rub or scrape more
sample from a sampling location. Typically, the swab is used to
sample buccal (cheek) cells from the inside of a subject's mouth.
However, the swab may also be used to take forensic samples, for
example. Polypropylene has the advantage that it does not absorb
water or DNA. For this reason, it is efficient at transferring high
yields of sample. A suitable swab is the Texwipe scourswab, model
no. TX8641, produced by the Texwipe Company LLC, Upper Saddle
River, N.J. 07458, USA. Such a swab has typical dimensions as
follows: swab head 16.8 mm long and 7 mm wide at widest point; swab
shaft (including tongue 18) 146 mm long and 3 mm wide.
[0124] In a typical use, the first step is the sampling step, e.g.
a subject rubs the inside surface of their cheek to load cellular
material onto the swab head. The cellular material is loaded on the
outer surface of the swab head (e.g. between ridges on the swab
head) and in the space between the segments 22a,b and the tongue
18. Subsequent steps are shown by FIGS. 1-8, which are described in
detail below.
[0125] In FIG. 1, the swab 10 is inserted, head 14 first, into the
open end of a tubular container 30. Container 30 has a generally
circular cross-section (as shown by FIG. 2) but is not wholly
cylindrical. Instead, the base 32 of the container 30 is rounded.
This allows the analysis of small volumes of fluid in the container
30. Also, the side walls 34,36 of the container 30 taper towards
each other in a direction away from the open end of the container
30. For convenience, opposing side walls 34,36 are labelled
separately but of course in the present case of a container 30 with
a cylindrical cross-section, there is a single, continuous side
wall.
[0126] FIG. 2 shows a lateral cross-sectional view along line A-A'
in FIG. 1. The swab head 14 has a generally oval (or pointed oval)
cross-sectional shape, and the tongue 18 has a generally
rectangular cross-sectional shape. With the swab head 14 in the
position shown in FIGS. 1 and 2, the swab head 14 does not touch
both of the inner surface of the side walls 34,36.
[0127] The swab head 14 is pushed further into the container 30 in
FIG. 3. At the point shown in FIG. 3, the swab head is pressed
lightly between the side walls 34,36 due to the tapering of the
side walls 34,36. FIG. 4 shows a lateral cross-section along line
B-B' in FIG. 3. FIG. 4 shows that the cross-sectional shape of the
swab head 14 changes due to the deformation imposed by the side
walls 34,36. The deformation involved is the forcing-apart of the
segments 14a,b which make up the swab head 14.
[0128] FIG. 5 shows the subsequent step where the swab head 14 has
been forced as far as it can go into the container 30. At this
point, the swab head is jammed between the side walls 34,36 of the
container 30. Further forcing of the swab into the container (by a
user pressing down on shaft 12) moves the shaft 12 with respect to
the swab head 14. The tongue 18 pierces the base of the swab head
14, until the tongue abuts against the inner surface of the base of
the container 30. Thus, the shaft 12 moves with respect to the swab
head 14 and the constricted portion 16 of the shaft 12 is forced
into the swab head 14. The wider portion of the shaft 12 is thereby
interposed between the upper portions 22a and 22b of the swab head,
forcing the segments 14a,b apart slightly at this location. FIG. 6
shows that the segments 14a,b are moved apart further than in FIG.
4.
[0129] Finally, in FIG. 7, the shaft 12 is pulled up from the
container 30. The swab head 14 at least partially breaks into its
component segments 14a,b by the withdrawal of the tongue 18 and
particularly by the broken projecting connection elements 20 which
help to break the light bond between the segments 14a and 14b. As
shown by FIG. 8, the segments 14a and 14b break away from each
other once the shaft 12 is removed from the container. This leaves
a space 38 in the container along the axis of the container. Sample
held within the swab head is therefore easily accessible, thereby
improving the efficiency of the sampling process. Furthermore, the
space 38 left along the axis of the container means that it is not
necessary to remove the remains of the swab head from the
container, since the sample is easily accessible along the axis of
the container. The need for removal of the swab head would
introduce an element of risk of contamination of the sample.
Elimination of this need eliminates that particular risk of
contamination.
[0130] A particular advantage associated with this embodiment is
that the space 38 left in the container allows the easy application
of automated assaying equipment to the kit. The space 38 allows
sample to be extracted easily from the container using automated
probes, and equally allows the easy introduction of buffers and/or
reagents into the container using automated probes.
[0131] Suitable containers 30 for the kit are containers which also
can be arranged in an array to allow multiple testing of samples
held in each container. In particular, the containers can be
containers (either fixed or removable) for 96 well plates (or
microtubes), a standard 8.times.12 format for genomic automated
processes such as DNA testing, e.g. >1 ml tubes. Suitable
products include the Riplat.TM. microtube rack systems (catalogue
numbers 602100, 602200, 602300, 602350, 602101, 602201, 602110,
602112, 602400, 602500, 602450, 602550) and the 2.4 ml and 1 ml
deep well plates of the same supplier (catalogue numbers DW850301,
DW850276), all available from Elkay Laboratory Products (UK) Ltd.,
Basingstoke, Hampshire RG24 8NA, UK. Other suitable products are
the 2.2 ml storage plate, the 2.2 ml storage plate Mark II and the
1.2 ml storage plate (catalogue numbers AB-0932, AB-0661, AB-0564,
respectively), all available from Abgene, Epsom, Surrey KT19 9AP,
UK. Similar plates are available from other manufacturers.
[0132] Following sampling and introduction and separation of the
swab head into the container, DNA testing may be carried out.
Suitable DNA isolation kits for use with embodiments of the present
invention include those using magnetic bead and filter techniques,
e.g. QIAamp DNA blood mini kit (catalogue no. 51104) and QIAamp 96
DNA blood kit (catalogue no. 51161), both available from Qiagen
Ltd., Boundary Court, Gatwick Road, Crawley, West Sussex RH10 2AX,
UK. Also suitable are nucleospin multi-96 blood kit (catalogue no.
K-3062-1) and nucleospin blood kit mini kits (catalogue no.
K-3052-1), both available from BD Biosciences Clontech UK, 21, In
Between Towns Road, Cowley, Oxford OX4 3LY, UK. Also suitable is
Agowa Mag Maxi DNA isolation kit, from AGOWA GmbH Glienicker Weg
185, D-12489, Berlin, Germany. Also suitable are magnetic bead kits
under development at DR1 (DNA Research Innovation Ltd), 940
Cornforth Drive, Sittingbourne Research Centre, Kent ME9 8PX.
[0133] Alternative types of container are illustrated in FIGS. 9
and 10. In FIG. 9, the container 40 has a rounded base 42 with a
generally cylindrical outer surface 44. In other words, the
container does not have tapering walls. Instead, the inner surface
of the side walls of the container presents a step 48 which
increases the cross-section or cross-sectional area of the
container in a stepwise fashion in a direction away from the open
end 46 of the container. Substituting now the container 40 of FIG.
9 into the sequence of events shown in FIGS. 1-8, the cross-section
of the open end 46 of the container is just large enough to allow
the intact swab head to be inserted into the end 46, but with some
deformation of the swab head 14 due to pressure against side walls
50,52. The cross-section of the container may taper at the open end
46 to facilitate insertion of the swab head into the container.
[0134] When the swab head passes the step 48, the pressure on the
sides of the swab is relaxed and the swab head (being slightly
elastic) can return to its original shape. Subsequently, upwards
movement of the swab forces the swab head 14 against step 48. The
abrupt reduction in cross-section of the container in the upwards
direction does not assist the swab head in passing through the
constriction. Consequently, the swab head is trapped against the
step 48. If the swab handle (shaft 12) is pulled up further, the
swab head detaches from the handle and falls back into the
container 40. Thus, the risk of contamination of the sample is
avoided during the detachment of the swab head from the shaft
12.
[0135] FIG. 10 shows a similar container 54 to the container 40
shown in FIG. 9. In FIG. 10, the container 54 has a tapering
section 56 at its inside side surface. This taper is sufficient to
deform the swab head 14, but insufficient to detach it from the
shaft 12. The tapering section ends abruptly in a step 58 which
widens the cross-section of the container again. Removal of the
shaft 12 from the container causes the swab head to become detached
due to abutment with step 58, in a similar way to that described
with respect to FIG. 9.
[0136] FIG. 11 shows another embodiment of a kit 60 according to
the present invention. The kit as illustrated is (schematically) as
it would appear to a user before using the kit. A swab 10 is
located in a container 62. Again, the swab has shaft 12 and swab
head 14. The container has a lid 64 which fits over the side walls
of the container. Lid 64 has a hole at its centre through which the
shaft 12 of the swab extends. For use, the swab is removed from the
container 62 by removing the swab 10 and the lid 64 together from
the rest of the container. The lid 64 therefore remains in place
with respect to the shaft 12. The swab is used to collect a sample
(with the lid still on the shaft) and then the swab is placed back
inside the container 62 and the lid reattached over the side walls
of the container. Subsequently, the user draws the shaft of the
swab upwardly with the lid remaining in place with respect to the
rest of the container. When the swab head 14 reaches the lid 64, it
presses against it due to the upwards force exerted on the shaft 12
by the user. The inner surface 66 of the lid detaches the swab head
from the shaft 12 and the shaft can be removed completely from the
container. The detached swab head then falls to the base of the
container for further processing/analysis, for example as referred
to above with respect to DNA assays or pharmacogenomic or forensic
applications.
[0137] FIGS. 12-16 illustrate variations on the embodiment
described with respect to FIG. 11. In FIG. 12, the lid is a stopper
70. The abutment surface 72 of the stopper facing the inside of the
container is shaped to facilitate removal of the swab head. In
particular, the abutment surface 72 of the stopper tapers towards
the swab head 14. As the swab is pulled out from the container, the
swab head 14 is wedged open into its components segments 14a,b by
the tapering abutment surface 72. The surface 72 in FIG. 12 is
shown as part of a cone, but other shapes can be used. In
particular, the shape can be a partial curved cone which tapers
non-uniformly, e.g. as shown by surface 74 arranged around hole 76
in FIGS. 13 and 14. Additionally or alternatively, the surface may
include a blade section 78, as shown by FIGS. 15 and 16. This
assists in separating the segments of the swab head.
[0138] The advantage of the separation of the swab head has already
been described with respect to FIGS. 1-8 and will not be repeated
here.
[0139] FIGS. 23-25 show an alternative embodiment to the
embodiments shown in FIGS. 12-16. In FIG. 23, a container 100
receives an assembly of a swab (consisting of handle 12 and swab
head 14) and s stopper 102. Stopper 102 has a sealing cap 104 and
an extended neck portion 106. A cylindrical bore 108 is formed
along the longitudinal axis of the neck portion 106 and cap 104.
Within the cylindrical bore 108 is located the shaft 12 of the
swab. The fit between the shaft 12 and the bore 108 is such that
stopper 102 and handle 12 are slidable with respect to each
other.
[0140] FIG. 24 shows the kit of FIG. 23 when the stopper is located
within container 100. Cap 104 forms a seal (e.g. a fictional seal)
with the open end of container 100. As shown in FIG. 24, when the
stopper 102 is in place closing the container 100, the neck portion
106 extends between two-thirds and three-quarters of the axial
length of the container 100. Beyond the lower end 110 of the neck
106 is located the swab head 14. Due to the length of the neck 106,
the swab head 14 is located close to the closed end (i.e. base) of
container 100.
[0141] FIG. 25 shows the kit of FIGS. 23 and 24 after the swab head
14 has been detached from the swab handle 12. The mode of
detachment of the swab head 14 from handle 12 is similar to that
described in respect of FIGS. 12-16. However, a significant
difference between this embodiment and the embodiments described in
relation to FIGS. 12-16 is the positioning of the tapering contact
surface 112 with respect to the container 100. Since it is the
abutment between the swab head 14 and surface 112 which acts to
detach the swab head 14 from the handle 12 (on relative movement
between the swab handle 12 and the stopper 102), the detachment
takes place at a position which is deep inside container 100. For
this reason, the swab head 14 has only a small distance to travel
to rest at the base of container 100. This reduces the likelihood
of the swab head becoming wedged sideways, for example, at an upper
portion of the container 100. An advantage here is that, by
ensuring that the swab head 14 is located deep within container
100, it is less likely that the swab head will interfere with
subsequent processing. In particular, ensuring that the swab head
14 does not become trapped at a shallow portion of container 100
allows probes (e.g. robotic probes) to be inserted part way into
container 100 during subsequent processing of the biological sample
(e.g. DNA assaying).
[0142] In an alternative embodiment to that shown in FIGS. 23-25,
stopper 102 may be releasably attached to handle 12. The advantage
of this is that the stopper may be used as a handle by the user of
the swab. This is helpful because a thicker handle is easier for a
user to manipulate. The means attaching stopper 102 to handle 12
can be a frangible connection between the two. The frangible
connection is broken, for example, when the stopper is brought into
engagement with the container. Then handle 12 can be moved with
respect to stopper 102 in order to detach the swab head from the
handle, as described with respect to FIGS. 23-25.
[0143] FIGS. 26-29 show another modification of the embodiment
described in relation to FIGS. 23-25. Stopper 102 again has an
extended neck portion 106. However, in this case, a pair of slots
114 is formed in neck portion 106. Slots 114 extend axially from
end 110 of the neck portion to a stop limit 116. Slots 114
communicate with cylindrical bore 108. Slots 114 are shown in FIG.
29.
[0144] Handle 12 includes protruding lugs or arms 118. These are
located close to the swab head 14. Arms 118 are shaped to be able
to slide along slots 114 up to the stop limit 116.
[0145] FIG. 27 shows the kit after cap 104 has closed the open end
of container 100. Furthermore, handle 12 has been moved upwardly
with respect to stopper 102 in order to detach swab head 14 from
the handle. The upwards travel of handle 12 is limited by the
abutment of arms 118 with stop limit 116 of slots 114.
[0146] As shown in FIG. 28, the handle 12 and the stopper 102 can
be removed from the container by pulling on handle 12. In this way,
the number of steps required to prepare the sample for analysis can
be reduced. In particular, the removal of stopper 102 with handle
12 is suited to robotic processing of the sample. The reduction in
the number of processing steps and the suitability for large scale
robotic analysis can reduce the risk of contamination (including
cross-contamination) of the sample.
[0147] FIG. 30 shows a schematic longitudinal cross-sectional view
of another embodiment of the invention. The swab is not shown in
FIG. 30. Instead, FIG. 30 shows the container 200 with an adapter
210 attached to the open end of the container by ultrasonic
welding. Alternatively, the adapter may be attached via cooperating
screw threads at the outer wall of container 200 and the inner wall
of adapter 210. Also shown in FIG. 30 is a rubber stopper 220 with
integral sealing rings 222 shaped for sealing engagement with inner
wall surface 224 of adapter 210. Stopper 220 is attached to
container 200 (or alternatively to adapter 210) by an integral
strap 226. Strap 226 may have a line of weakness 228 formed close
to the container, to allow the stopper 220 to be detached from the
container or adapter during subsequent processing of the
sample.
[0148] FIG. 31 shows a lateral cross-sectional view along lines
H-H' in FIG. 30. Aperture 210 has a rigid diaphragm portion 230
extending perpendicularly away from inner wall 224. Diaphragm
portion 230 has an elongate slot 232 formed in it which, when the
adapter 210 is fitted on the container 200, defines an aperture
between the internal space of the container and the outside world.
Slot 232 is shaped and sized to allow the swab head 14 through in
one rotational position, but not at another rotational position
(e.g. perpendicular to the first rotational position).
[0149] The operation of this embodiment is shown in FIGS. 32 to 34
which all show schematic longitudinal cross-sectional views of the
kit. In FIG. 32, swab 10 has been inserted into the container 200
via slot 232 in adapter 210. This has been achieved by inserting
the swab head into the container (in the direction of arrow X) in
the first rotational position, namely with the broad faces of the
swab head being parallel to the axis of insertion into the
container and perpendicular to the plane of the paper.
Subsequently, the swab handle is rotated by 90.degree. in the
direction of arrow Y. This gives the arrangement shown in FIG. 33.
Here, the broad face 15 of the swab head is parallel with the plane
of the paper. Next, the user moves the swab handle in direction Z.
The shape of the slot 232 is such that the handle 12 of the swab is
able to move up and down in slot 232. However, in this second
rotational position, the swab head 14 is not able to pass through
slot 232. Due to the rigid nature of diaphragm 230, and due to its
strength, the swab head 14 is detached from handle 12 by further
upwards movement of the swab handle relative to the adapter 210 in
direction Z. The handle may then be removed from the container and
disposed of. As shown in FIG. 34, the stopper 220 may then be used
to seal the container by sealing engagement of the rings 222 with
internal wall 224 of adapter 210. The stopper 220 has a broad
removal flange 234, this is to facilitate removal of the stopper
during subsequent processing of the sample, for example in a
laboratory. At that stage, the stopper 220 may be removed from the
container. If desired, strap 226 may be broken at line of weakness
228, and stopper 220 may be disposed of.
[0150] The embodiment shown in FIGS. 30 to 34 is particularly
suited to small-volume containers, for example 0.25 ml volume
containers. It is intended that adapter 210 is not removed from the
container 200 during subsequent processing of the sample. For this
reason, slot 232 should be of suitable size to allow a probe to
pass into the container in order to introduce or remove reagent,
sample or processed sample 2/from the container.
[0151] FIGS. 35 and 36 both show schematic longitudinal
cross-sectional views of another embodiment of the invention. This
embodiment is particularly suited to larger-volume containers than
the previous embodiment. For example, this embodiment is suitable
for containers of volume of about 1 ml. This embodiment may be
considered a modification of the embodiment shown in FIG. 12. In
FIG. 35, the swab head has a stopper 250 slidably located on handle
12. The stopper 250 includes an aperture 252 extending
therethrough, shaped to allow a snug fit around handle 12, allowing
sliding with respect to handle 12, but not to allow swab head 14 to
pass along aperture 252. With stopper 250 located on the handle 12,
the swab is used by a subject to take a sample of buccal cells.
Then, the swab head is placed in container 256 and the outer
surface 258 of stopper 250 is engaged with inner surface 260 of
container 256. These surfaces typically sealingly engage with each
other. Then, the user pulls handle 12 out of the container,
engaging swab head 14 with bottom surface 254 of stopper 250.
Further upwards movement of handle 12 causes swab head 14 to become
detached from handle 12 by abutment with surface 254.
[0152] After removal of the handle 12 from container 256, lid 262
may be used to seal the container. Lid 262 may be formed from
rubber, or it may be a more rigid material. For example, it may
cooperate with a screw thread 264 formed on the outer surface of
container 256. In a similar way to the embodiment of FIGS. 30 to
34, lid 262 may have a strap 266 which attaches it to container
256. Strap 266 may include a line of weakness 268. During
subsequent processing of the sample, lid 262 may be removed from
the container, and, if desired, strap 266 may be broken at line of
weakness 268 to remove lid 262 completely from the kit. The lid may
then be disposed of, if desired.
[0153] The structure of the swab head itself has already been
described with reference to FIG. 17. FIGS. 18-20 illustrate
modifications of the swab structure, in particular modifications of
the size and shape of the projecting connection elements 20. In
FIG. 18, the connection elements 20 are directed to curve upwardly
from the tongue 18 with respect to the swab head. This can assist
in breaking the swab head segments apart when the tongue 18 moves
downwardly with respect to the swab head 14. In FIG. 19, the
connection elements 20 are directed to curve upwardly from the
tongue 18. This can assist in breaking the swab head segments apart
when the tongue 18 moves upwardly with respect to the swab head 14.
In FIG. 20, the connection elements 20 are enlarged compared to the
connection elements of the embodiment illustrated by FIG. 18. This
can provide extra stiffness to the swab head as a whole and also
can assist in breaking the swab head segments apart during movement
of the tongue 18 with respect to the swab head.
[0154] Another embodiment of the invention is illustrated in FIG.
21. The kit includes a swab 10, a sleeve of paper 80 and a
container 82. The sleeve of paper 80 is shaped and sized to fit
snugly around the swab head 14. The paper is absorbent, typically
absorbing water and/or aqueous solutions. In particular, the snug
fit allows sample held by the swab to be transferred (e.g. by
leaching) from the swab to the paper sleeve 80. This is enhanced by
the fact that polypropylene (the material of the swab) is
non-absorbent.
[0155] In one embodiment, after the swab head 14 is located within
the sleeve 80, the combination is placed into the container 82 for
storage. The container may be a container, e.g. similar to one of
the containers illustrated and described with respect to FIGS. 1-8
or FIGS. 9 and 10 or FIGS. 11-16.
[0156] In another embodiment, the sleeve is first fitted within the
container 82 before the swab head is located within the sleeve. An
advantage of this is that the sleeve need only be handled by way of
the outside surface of the container. This can avoid contamination
problems. The sleeve is a snug fit within the container 82. In this
way, the sleeve can be pressed between the swab head 14 and the
inside surface 84 of the container 82. This can assist in the
efficient transfer of sample from the swab head 14 to the sleeve
80.
[0157] FIG. 22 illustrates an embodiment of a modified container
for use, e.g. with the kit arrangement of FIGS. 1-8. In this
figure, a container 86 of a similar shape to the container 30 of
FIG. 1 is shown. A partial lining 88 of absorbent material is
located on the inside surface of the container 86. The lining 88 is
located at or close to the final location of a detached (and split)
swab head in the container 86 after use of the kit. Use of a
tapering container means that the swab head 14 is detached from the
shaft 12 due to pressure between the inner surface of the container
86. Since the inner surface of the container is lined with the
absorbent lining, the swab head is pressed against this lining.
This further improves the transfer of sample from the swab head to
the lining.
[0158] The absorbent material used in these embodiments is
typically an impregnated sample collection paper, e.g. a treated
filter paper. The sample is typically collected from the swab head
onto the paper and allowed to dry. This can be an efficient, stable
and cost-effective method for storing biological samples. The
treated paper can yield high quality nucleic acid for PCR
amplification. The treatment of the paper allows the paper to
disrupt intact cells and release nucleic acids from nucleated cells
in blood, eukaryotic cells, bacteria or virus particles. After
drying, the sample can be rehydrated and then amplifiable nucleic
acids can be eluted from the paper. Alternatively, DNA (for
example) can be amplified from the paper itself. The paper is
treated in such a way that substances which inhibit PCR reactions
(e.g. haemoglobin in blood samples) become fixed to the matrix of
the paper and are not released with template nucleic acids.
Suitable material is available in the form of modified filter paper
called IsoCode.TM. (e.g. catalogue no. 495020, 495000, 495005,
495015, 495017, 495025), available from Schleicher & Schuell,
P.O. Box 4, D-37582 Dassel, Germany or Keene, N.H. 03431, USA. The
content of U.S. Pat. Nos. 5,939,259, 6,168,922, 5,807,527 is
incorporated herein by reference.
[0159] Use of the treated absorbent paper in the container allows
the paper to process (i.e. commence nucleic acid release) from the
sample transferred to it from the swab head during shipment of the
sample. This can greatly reduce the time taken to process the
sample and can remove yet another step from the processing of the
sample which could otherwise give rise to a risk of
contamination.
[0160] Use of the swab described provides a high yield of
biological material due to the non-absorbent nature of the swab
head material, and also due to the large surface area of the swab
head and its rigid surface (which makes it relatively abrasive).
The absorbent paper can allow longer term storage of the sample at
room temperature.
[0161] The embodiments described above are examples only.
Modifications of these embodiments, further embodiments and
modifications thereof will be apparent to the skilled person and as
such are within the scope of the invention.
* * * * *