U.S. patent application number 13/901848 was filed with the patent office on 2017-06-22 for device, apparatus and method for performing separations.
This patent application is currently assigned to Waters Technologies Corporation. The applicant listed for this patent is Waters Technologies Corporation. Invention is credited to Jonathan Belanger, Stephen J. Shiner, Micah Inglis Watt.
Application Number | 20170173497 13/901848 |
Document ID | / |
Family ID | 39808846 |
Filed Date | 2017-06-22 |
United States Patent
Application |
20170173497 |
Kind Code |
A9 |
Belanger; Jonathan ; et
al. |
June 22, 2017 |
DEVICE, APPARATUS AND METHOD FOR PERFORMING SEPARATIONS
Abstract
Embodiment of the present invention feature a device having a
body, a separation media and a frit element. The exterior surface
of the body has a first attachment means positioned radially about
at least one of the media chamber and the frit section to form a
compact assembly.
Inventors: |
Belanger; Jonathan;
(Whitinsville, MA) ; Watt; Micah Inglis;
(Fitchburg, MA) ; Shiner; Stephen J.; (Holden,
MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Waters Technologies Corporation |
Milford |
MA |
US |
|
|
Assignee: |
Waters Technologies
Corporation
Milford
MA
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20130256231 A1 |
October 3, 2013 |
|
|
Family ID: |
39808846 |
Appl. No.: |
13/901848 |
Filed: |
May 24, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12526286 |
Sep 30, 2010 |
8449769 |
|
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PCT/US2008/054237 |
Feb 19, 2008 |
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13901848 |
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61025416 |
Feb 1, 2008 |
|
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60891091 |
Feb 22, 2007 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
Y10T 29/49826 20150115;
G01N 30/08 20130101; G01N 30/6004 20130101; G01N 30/6026 20130101;
G01N 2030/085 20130101; B01D 15/12 20130101; G01N 2030/085
20130101; B01D 15/22 20130101; G01N 30/603 20130101; G01N 30/6039
20130101 |
International
Class: |
B01D 15/22 20060101
B01D015/22 |
Claims
1-33. (canceled)
34. A separation device comprising: a body having a media chamber
configured to hold a media, a connection section configured to
place the media chamber in fluid communication with a source of
fluid, and at least one frit section in fluid communication with
the media chamber; a frit element held in the at least one frit
section; and a separation media disposed within the media chamber,
wherein the separation media is held within the media chamber by
the frit element.
35. The separation device of claim 34, wherein the at least one
frit section is disposed at a first end of the media chamber.
36. The separation device of claim 35, further comprising a second
frit element disposed at a second end of the media chamber.
37. The separation device of claim 34, further comprising a rod
assembly and a compression fitting, the compression fitting
configured to couple the rod assembly to the body.
38. The separation device of claim 37, wherein the rod assembly
includes a tube section and a compression plate section, wherein
the compression fitting engages the compression plate to couple the
rod assembly to the body.
39. The separation device of claim 37, wherein the compression
fitting has an interior surface defining a tube channel, the tube
channel configured to receive the tube section of the rod assembly
therethrough.
40. The separation device of claim 37, wherein an exterior surface
of the compression fitting comprises turning surfaces.
41. The separation device of claim 40, wherein the turning surfaces
are recessed.
42. The separation device of claim 40, further comprising a tube
compression assembly.
43. The separation device of claim 42, wherein the tube compression
assembly comprises a ferrule and a ferrule fitting.
44. The separation device of claim 43, wherein the ferrule fitting
is received on the tube section extending from the compression
fitting.
45. The separation device of claim 42, wherein the tube compression
assembly conceals the turning surfaces.
46. The separation device of claim 34, further comprising a wiper,
wherein the media chamber further comprises a wiper recess
configured to receive the wiper, the wiper comprising a resilient
ring.
47. The separation device of claim 34, further comprising a
compression element, the compression element compelled into the
separation media disposed within the media chamber to occupy a
volume in the range of about 0.1% to about 5% of a total volume
occupied by uncompressed particles of the separation media.
48. The separation device of claim 47, wherein the compression
element is compelled into the particles to occupy a volume of about
2% of the total volume occupied by uncompressed particles of the
separation media.
49. The separation device of claim 47, wherein the compression
element is compelled into the particles to form an interstitial
volume fraction in the range of about 0.38 to about 0.35.
50. The separation device of claim 49, wherein the interstitial
volume fraction is in the range of about 0.365 to about 0.375.
51. The separation device of claim 49, wherein the compression
element compelled into the particles to effect a reduction of an
at-rest interstitial volume fraction in the range of about 5% to
about 15%.
52. The separation device of claim 51, wherein the reduction is in
the range of about 8% to about 12%.
53. A method of separating compounds in a solution from each other
or undesired components of the solution, comprising: providing a
separation device having a body, a separation media, and a frit
element; the body having a media chamber configured to hold a
media, a connection section configured to place the media chamber
in fluid communication with a source of fluid, and at least one
frit section in fluid communication with the media chamber, the
frit element held in the at least one frit section, and the
separation media disposed within the media chamber for effecting
separations of compounds in solutions flowing therethrough; and
flowing a fluid through the device to separate one or more
compounds.
54. The separation device of claim 53, further comprising a rod
assembly and a compression fitting, the compression fitting
configured to couple the rod assembly to the body.
55. The separation device of claim 55, wherein an exterior surface
of the compression fitting comprises turning surfaces.
56. The separation device of claim 55, further comprising a tube
compression assembly.
57. The separation device of claim 56, wherein the tube compression
assembly conceals the turning surfaces.
58. A method of making a separation device comprising: providing a
body, a separation media, at least one frit element, and at least
one compression element; the body having a media chamber configured
to hold a media, a connection section configured to place the media
chamber in fluid communication with a source of fluid, and at least
one frit section in fluid communication with the media chamber;
placing the at least one frit element in the at least one frit
section for retaining the separation media; placing the separation
media within the media chamber for effecting separations of
compounds in solutions flowing therethrough; and placing the
compression element in the body to compress the separation media to
form a stable separation media.
59. The method of claim 58, wherein the compression element
comprises a second frit element.
60. The method of claim 58, wherein the compression element is
compelled into the separation media to occupy a volume in the range
of about 0.1% to about 5% of a total volume occupied by
uncompressed particles of the separation media.
61. The method of claim 58, wherein the compression element is
compelled into the separation media to occupy a volume of about 2%
of the total volume occupied by uncompressed particles of the
separation media.
62. The method of claim 58, wherein the compression element is
compelled into the particles to form an interstitial volume
fraction in the range of about 0.38 to about 0.35.
63. The separation device of claim 58, wherein the interstitial
volume fraction is in the range of about 0.365 to about 0.375.
64. The separation device of claim 58, wherein the compression
element is compelled into the particles to elect a reduction of an
at-rest interstitial volume fraction in the range of about 5% to
about 15%.
65. The separation device of claim 64, wherein the reduction is in
the range of about 8% to about 12%.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit of and priority to U.S. Ser.
No. 60/891,091 filed Feb. 22, 2007 and U.S. Ser. No. 61/025,416,
filed Feb. 1, 2008, the entire contents of which is incorporated
herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND
DEVELOPMENT
[0002] The present invention was not made with Federal funding.
FIELD OF THE INVENTION
[0003] The present invention relates to devices, methods and
apparatus for performing separations, and, in particular,
separations performed by chromatography for analytical
purposes.
BACKGROUND OF THE INVENTION
[0004] The present invention relates to devices, methods and
apparatus for performing chemical separations, and, in particular,
for performing chromatography. The term "chromatography" refers to
the separation of compounds based on differences in affinity or
absorbance. In chromatography, compounds are held in a solution of
a gas, liquid or supercritical fluid. The solution in which the
compound is dissolved is known as the "solvent". The dissolved
compounds exhibit differences in absorbance or affinity to a media
that is not dissolved in the solvent. This media is held in place,
stationary to the flow of a solution holding the dissolved
compounds. This media is commonly a solid phase material.
[0005] Chromatography is a common research tool and can be used to
process samples for analysis by various detection techniques.
Chromatography is used to grossly separate many compounds from a
sample, as an extraction technique. Chromatography can also be
utilized as a fine separation technique in which subtle changes in
molecular structure and function alter the affinity of the
compounds to an immobilized media. Closely related compounds, for
example drugs and drug metabolites, can be effectively
separated.
[0006] Chromatography is performed in open systems or closed
systems. In open systems chromatography is performed without
significant pressure differentials. Examples of devices used in an
open type system are well-like devices, such as ninety-six well
extraction plates.
[0007] An example of a closed system is high performance or high
pressure liquid chromatography (HPLC). Closed chromatography is
normally performed with columns and cartridges through which
solutions are pumped under pressure. The columns and cartridges
typically have a packing of an immobilized media, such as silica or
polymeric particles, to which compounds adsorb. A sample is flowed
through the media and compounds in the sample adsorb to the media.
This paper will make no distinction between a column and cartridge,
and will use the term "column" to mean column or cartridge unless
specifically stated otherwise. Analytical columns are columns made
with fine tolerances for effecting reproducible qualitative and
quantitative separations of closely related compounds. Columns, and
analytical columns, in particular, are expensive.
[0008] The initial flowing of sample onto the media is called
"loading". Removing the potential compounds of interest is known as
"eluting". Elution is often performed by changing the solvent
composition. Preparing the media to receive the sample is known as
"conditioning", Ensuring the prior sample is removed from the
media, to allow a next sample to be loaded on the media is known as
"washing".
[0009] The term "sample" will be used to denote any material that
is received for processing. In clinical settings, a sample may
comprise a biological fluid or tissue. The term "analyte" will be
used to mean a composition of interest, potentially present in a
sample. Samples and solvents may contain particulates, globules and
other materials that are not of analytical or diagnostic interest.
For simplicity, this paper will refer to all such particulates,
globules and materials as particulates. These particulates may
accumulate and reduce flow in columns such that the column no
longer is useful.
[0010] Columns are normally in fluid communication with a detector.
As used in this paper, the term "detector" refers to a device that
produces a signal in response to the presence or absence of a
composition. A typical detector is in the nature of, by way of
example, without limitation, mass spectrometers, optical sensors,
such Raman detectors, light scattering detectors, fluorescent
detectors, chemi-luminescent detectors, light absorbance detectors,
light refraction detectors, electrochemical detectors, viscosity
detectors, nuclear magnetic resonance detectors.
[0011] HPLC is normally performed at pressure of up to 5,000 pounds
per square inch (psi). However, there is a desire to operate at
pressures above 5,000 psi, including pressures in the extreme
pressure region of 5,000 psi up to 15,000 psi. At such elevated
pressures and with higher flow rates associated with such
pressures, the size of columns and conduits to effect fluid
communication between fluidic elements is generally reduced. With
the smaller size, columns are more sensitive to particulates and
pressure pulsation. As used herein, pressure pulsation refers to
the changes in pressure associated with pump, valve and other
mechanical inefficiencies and errors.
[0012] Guard columns are used to protect and extend the useful life
of analytical columns. However, the use of guard columns to protect
other columns, such as an analytical column, often entails
substantial additional conduits and tubing. The additional tubing
and conduits adds to the potential of leaks and contributes to band
spreading due to the effects of the walls of the conduits and
tubes, and decreases the responsiveness of the system to changes in
fluids during elution process or washing processes.
[0013] Thus, there is a need for devices, methods and apparatus
which function to protect a column and detector sensitive to the
effects of particulates and pressure pulsations and ripples in a
high pressure and extreme high-pressure environment.
SUMMARY OF THE INVENTION
[0014] Embodiments of the present invention feature a device,
apparatus and method of separating one or more compounds of
interest from each other or from undesired compounds or
particulates. One embodiment of the device has a body, a separation
media and a frit element.
[0015] The body has an interior body surface, an exterior body
surface, a first body opening at a first body end and a second body
opening at a second body end. The first body opening and the second
body opening define a boundary between the interior body surface
and the exterior body surface. The interior body surface has at
least one wall creating a passage in the body. The passage has at
least one frit section and a media chamber proximal to the first
opening and a manifold section proximal to the second opening. The
frit section is for holding a frit element. The media chamber is
for holding a separation media. The manifold section is for
receiving or discharging fluid from the frit section. The exterior
body surface has a first union means and at least one of the
exterior body surface and the interior body surface has a second
union means. The first union means is towards the first opening for
placing the media chamber in fluid communication with either a
source of fluid or a fluid discharge conduit or a column or
detector. The second union means is towards the second opening for
placing the manifold section in communication with either a source
of fluid or a fluid discharge conduit or a column or detector. The
exterior surface has a first attachment means positioned radially
about at least one of the media chamber and the frit section.
[0016] The separation media is held within the media chamber for
effecting separations of compounds in solutions flowing
therethrough. The frit element is held in the frit section for
retaining the separation media. The body receives a first conduit
attachment means and a second attachment means to place said
passage in fluid communication with a solution to effect separation
of one or more the compounds from other compounds in the solution
or undesired particulates.
[0017] Preferably, the device comprises a first frit element
received in the frit section and a second frit element. The second
frit is received at or about the first end in a second frit section
of the passage or about the exterior surface. For example, one
embodiment features an exterior surface having a rim extending
around the first opening for receiving a frit disc as a second frit
element. Preferably, the rim has a planar rim surface and at least
one rim ridge surrounding the first opening. The frit disc has a
planar disc surface for receiving the rim ridge and sealing the
frit disc upon compression against said rim.
[0018] Preferably, the device has a first union means fitted to the
frit disc. The first union means is for attachment to a conduit for
removing fluid from or placing fluid into the frit element, or to
place into communication with a column or a detector.
[0019] One preferred first union means comprises a rod assembly and
compression fitting. The rod assembly has tube section and a
compression plate section. The tube section is in fluid
communication with the frit disc. The plate section has a first
planar surface for pressing in sealing relationship to the frit
disc and a second surface for receiving a compression surface of a
compression fitting. The compression fitting is received on said
first attachment means of the body for compressing the plate
section and frit disc against the rim.
[0020] Preferably, the compression fitting has a fitting interior
surface and a fitting exterior surface, a first fitting opening and
a second fitting opening. The fitting interior surface defines a
tube channel between the first fitting opening and the second
fitting opening. The tube channel has a narrow section, an expanded
section and a compression surface. The compression surface is
interposed between the narrow section and the expanded section. The
expanded section and the attachment means of the body having
cooperating threads to allow the compression surface to compress
the plate section and frit disc on the rim with said tube section
received in and extending from the tube channel.
[0021] Thus, the rod assembly is received in the compression
fitting with the tube section in the tube channel and extending
outwardly from the first fitting opening, and the plate section
abutting the compression surface. Turning the compression fitting
with respect to the body compresses the plate section, the frit
disc and the rim of the body in sealing engagement. Preferably, at
least one of, and even more preferably, both the body and the
compression fitting have exterior surfaces that facilitate rotation
such as knurled surfaces, wrench receiving notches and other
turning surfaces. Preferably, the turning surfaces on the
compression fitting are recessed and are proximal to the second
opening. The recessed turning surfaces are preferably concealed by
a tube compression assembly. The tube compression assembly is
received on the tube section of the rod assembly to place the tube
section in fluid communication with a detector, column or
conduit.
[0022] Preferably, the tube compression assembly comprises a
ferrule and a ferrule fitting. Thus, the ferrule and the ferrule
fitting are received on the tube extending from the compression
fitting. The ferrule fitting has a ferrule fitting interior
surface, a ferrule fitting exterior surface, a ferrule fitting
first opening and a ferrule fitting second opening. The ferrule
fitting interior surface defining a ferrule fitting tube channel
between the ferrule fitting first opening and the ferrule fitting
second opening. The ferrule fitting tube channel has a ferrule
fitting narrow section and a ferrule fitting expanded section. The
ferrule fitting narrow section receives the tube section. The
ferrule fitting expanded section receives the compression fitting
turning surfaces to conceal such turning surfaces. Thus, the user
is discouraged from separating the body from the compression
fitting, potentially compromising the separation media contained
therein.
[0023] Preferably, the ferrule fitting has a male end at the
ferrule fitting second opening. And, preferably, the ferrule
fitting has a ferrule fitting rim for receiving the ferrule to
allow said ferrule to be compressed by a cooperating ferrule female
fitting. The male end and the female ferrule fitting, preferably
have cooperating threads.
[0024] Preferably, second body end has second end attachment means
for affixing, in fluid communication, to an analytical column,
detector or a conduit. For example, without limitation, second end
attachment means comprise cooperating threads for receiving
cooperating threads of a column, or a detector or conduit, or a
further fitting including ferrule compression fittings and the
like.
[0025] A further embodiment of the present invention comprises a
method of separating compounds in a solution from each other or
undesired components of the solution. The method comprises the step
of providing a device having a body, a separation media, and a frit
element as previously described, and flowing solutions through the
device to separate compounds from each other or from
particulates.
[0026] A further embodiment of the present invention comprises an
apparatus. The apparatus has a device as previously described and
one or more instruments selected from the group comprising a high
performance chromatography pump, detector and column.
[0027] Thus, embodiments of the present invention feature a device,
method and apparatus for separating one or more compounds from each
other or from particulates. The device has small internal volumes
and therefore does not contribute significantly to band spreading.
The device is readily manufactured and conceals features that would
potentially lead to undesirable opening of the separation
media.
[0028] These and other features and advantages will be apparent to
those skilled in the art upon reading the detailed description of
the invention and viewing the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] FIG. 1 depicts a cross-sectional view of a device embodying
features of the present invention;
[0030] FIG. 2 depicts a cross-sectional view of a device embodying
features of the present invention;
[0031] FIG. 3a depicts an exploded view of the device in FIG.
2;
[0032] FIG. 3b depicts an exploded view of the device in FIG. 1
with a wiper and projecting frit;
[0033] FIG. 3c depicts an detailed view of the device in FIG.
3b;
[0034] FIG. 4 depicts an exploded view of the device of FIG. 1;
and,
[0035] FIG. 5 depicts a view of the device of FIG. 1 in partial
cross-section with a further column, conduit, or instrument.
DETAILED DESCRIPTION OF THE INVENTION
[0036] Embodiments of the present invention will be described with
respect to a column used to protect a analytical column, commonly
referred to as a guard column with the understanding that such
column can be used for performing chromatography without an
analytical column. Indeed, such column can be used directly with
analytical, diagnostic instruments, detectors and the like. The
description that follows describes a preferred embodiment of the
device, methods and apparatus of the present invention. Those
skilled in the art will readily recognize that the present
invention can be modified and altered to address specific needs
without departing from the present teaching.
[0037] Turning now to FIG. 1, a device, generally designated by the
numeral 11 is depicted in cross-section. The device is for
separating one or more compounds of interest from each other or
from undesired compounds or particulates. The device 11 has the
following major components: a body 13, a separation media 15 and
frit element 17a and 17b.
[0038] As best seen in FIG. 2, the body 13 has an interior body
surface 21, an exterior body surface 23, a first body opening 25 at
a first body end 27 and a second body opening 31 at a second body
end 33. The first body opening 25 and the second body opening 31
define a boundary between the interior body surface 21 and the
exterior body surface 23. The interior body surface 21 has at least
one wall 35 creating a passage 37 in the body 13. The body 13, and
all components of the device 11, unless otherwise indicated, is
made of a substantially rigid material such as plastic and metal. A
preferred metal is titanium, brass, and stainless steel. The body
13, for extreme high pressure applications is approximately 2.1
millimeters in diameter and 5 millimeters in length. The passage 37
is about 0.050 to 0.0005 inches in diameter at its narrowest.
[0039] The passage 37 has at least one frit section 39a and a media
chamber 39b proximal to the first opening 25. And, the passage 37
has a manifold section 39c in fluid communication with the frit
section 39a and a connection section 39d more proximal to the
second opening 31.
[0040] The frit section 39a is for holding first frit element 17a.
The media chamber 39b is for holding the separation media 15, which
comprises a porous monolith, packed bed of particles, beads or
other solid forms or fibers [not shown], known in the art. The
separation media 15 is held within the media chamber 39b for
effecting separations of compounds in solutions flowing
therethrough. For guard column applications at extreme pressures,
chamber 39a has a volume of 17 to 19 cubic mm. When packed with a
bed of particles, the preferred particles are packed at similar
extreme pressures. A preferred particle bed has particles having a
mean diameter of 1.7 microns.
[0041] A first frit 17a is held in the frit section 39a for holding
the packed bed of particles in the media chamber 39b. First frit
17a is porous filter disc made of a material such as titanium,
plastic or stainless steel in a manner known in the art.
[0042] The manifold section 39c is for receiving from or
discharging to the frit section 39a. The connection section 39d is
constructed and arranged as a union means for receiving a fitting
[not shown] to place the manifold section in fluid communication
with a further conduit, instrument, or detector. Those skilled in
the art will readily recognize that such union means can be formed
as part of the exterior surface 23.
[0043] A second frit element comprising a second frit 17b and a
frit sealing ring 43a is received at or about the first body end 27
in a second frit section of the passage [not shown] in the manner
of the first frit 17a, or, as shown in FIGS. 2 and 3a, outside the
first body 13 end surface 27, or a combination of a second frit
section of the passage and projecting outside the passage surface
27 as shown in FIGS. 3b and 3c to be discussed in greater detail
below.
[0044] Returning now to FIGS. 2 ands 3a, second frit 17b, like
first frit 17a, is a porous filter disc made of a material such as
titanium, plastic or stainless steel. Second frit 17b is held in
frit sealing ring opening 63 of frit sealing ring 43a.
[0045] Exterior surface 23 has a rim 41 extending around the first
body opening 25. Rim 41 has a planar rim surface for receiving frit
sealing ring 43a. Turning now to FIG. 2a, frit sealing ring 43a has
a flat surface that mates with the flat surface of rim 41. At least
one of the flat surface of rim 41 and the flat surface of frit
sealing ring 43a has ridge. As depicted, in FIG. 2, the rim surface
41 has a ridge 45 surrounding the first opening 25. The frit
sealing ring 43a receives the ridge 45 against the ring flat
surface. The ridge 45 seals the frit sealing ring 43a upon
compression against said rim 41.
[0046] Turning now to FIGS. 3b and 3c, such figures depict an
embodiment in which the second frit 17b, is placed into the chamber
39b which would be occupied by particles of other separation media.
Preferably, a compression element, such as a sleeve [not shown],
frit sealing ring 43a, a wiper element 161, to be discussed in
greater detail later, or, as described herein, second frit 17b is
compelled into the media held in chamber 39b to occupy
approximately 0.1 to 5% of the total area occupied by particles not
under pressure. More preferably, the compression element such as
second frit 17b is forced into the at-rest particles to occupy
approximately 2% of the volume. Compression presses the particles
to form an interstitial volume fraction of approximately 0.38 to
0.35. And, preferably, compression presses the particles to form an
interstitial volume fraction of approximately 0.365 to 0.375. These
interstitial volume fractions represent a reduction of at-rest
interstitial volume fraction of approximately 5 to 15%, and
preferably of about 8 to 12%. The compressed particles have an
optimal bed density to promote stability of the bed and avoid the
formation of voids.
[0047] Thus, frit sealing ring 43a and second frit 17b are sized to
allow second frit 17b to project outside the frit seal ring opening
63. The amount of projection can be changed by changing the
thickness of the second frit 17b or the frit sealing ring 43a. The
portion of the second frit 17b projecting outside the opening 63,
as best seen in FIG. 3c, occupies a space of 2% of the volume of
the particles that would occupy chamber 39b. For a chamber of
approximately 18 cubic milimeters in volume and 2.1 mm in diameter,
the amount of projection is approximately 0.051 to 0.330 mm.
[0048] Again referring to FIGS. 3b and 3c, a wiper 161 is received
in a recess 163 in the passage 37 forming chamber 39b. The wiper
161 is a ring of resilient material such as plastic to provide
radial compression of the packed material forming the bed and to
facilitate the compression of the bed upon the pressing the second
frit 17b into the chamber 39b. A preferred plastic is a
fluoropolymer sold under the mark TEFLON.RTM. (Dupont). The second
frit 17b is normally fitted to the first body 13 after the
particles are loaded. The remainder of the structures of FIGS. 3b
and 3c are as described with respect to FIG. 3a.
[0049] Turning now to FIG. 2, the body 13 is fitted to conduits,
instruments and detectors by first union means comprising
cooperating fittings, conduits or structures associated with
instruments and detectors. First union means, as depicted,
comprises the exterior body surface 23 and attachment surfaces 51
positioned radially about at least one of the media chamber 39b and
the frit section 39a. Attachment surfaces comprise pins, cams and
locking fittings known in the art, and as illustrated, a threaded
section of the body 13.
[0050] Turning now to FIGS. 2 and 3, one first union means
comprises a rod assembly 55 and compression fitting 57. The rod
assembly is preferably made of rigid plastic, and metals such as
brass, titanium and stainless steel. The rod assembly 55 has a tube
section 59 and a compression plate section 61. The tube section 59
is in fluid communication via port 67 with the frit center opening
63 of second frit 17b.
[0051] The compression plate section 61 has a first plate surface
65a for pressing in sealing relationship against the corresponding
planar surface of frit sealing ring 43a. Preferably, at least one
of the plate surface 65a and the planar surface of the frit sealing
ring 43a has a ridge for effecting a seal. As depicted in FIG. 3a,
first plate surface 65a has a ridge 71 extending around the port
67. Upon compression the ridge 71 presses into and seals the frit
sealing ring 43a against the plate section 61. The compression
plate section 61 has a second plate surface 65b for receiving a
compression surface 73 of compression fitting 57.
[0052] Compression fitting 57 has a fitting interior surface 81 and
a fitting exterior surface 83, a first fitting opening 85 and a
second fitting opening 87. As best seen in FIG. 2, the fitting
interior surface 81 defines a tube channel 91 between the first
fitting opening 85 and the second fitting opening 87.
[0053] Tube channel 91 has a narrow section 93a, an expanded
section 93b and compression surface 73. The compression surface 73
is interposed between the narrow section 93a and the expanded
section 93b. The expanded section 93b and the attachment surfaces
51 of the body 13 have cooperating threads to allow the compression
surface 73 to compress the compression plate section 61 and frit
sealing ring 43a on the rim 41 of the body 13. The tube section 59
is received in and extends from the tube channel 91.
[0054] Rotation of the compression fitting 57 with respect to the
body 13 in one direction compresses the compression plate section
61, the frit sealing ring 43a and the rim 41 of the body 13 in
sealing engagement. Rotation of the compression fitting 57 in the
opposite direction causes decompression and loss of the sealing
engagement. Preferably, at least one of, and even more preferably,
both the body 13 and the compression fitting 57 have exterior
surfaces that facilitate rotation such as knurled surfaces, wrench
receiving notches and other turning surfaces. Such turning surfaces
facilitate manufacture of the device 11.
[0055] However, it is desirable to maintain the sealing
relationship of the compression plate section 61, the frit sealing
ring 43a and the rim 41 of the body 13 after the device is packed
with separation media 15. Disruption of the sealing relationship
disturbs the separation media 15 making such media less effective.
It is desirable in this regard to not allow or discourage rotation
of the compression fitting 57 and the body 13 after the device 11
is made. As best seen in FIGS. 3 and 4, compression fitting 57 has
an exterior surface 83 having turning surfaces 95 in the form of
notches for receiving a wrench or similar tool [not shown]. The
turning surfaces 95 are recessed and are proximal to the second
opening 87.
[0056] The turning surfaces 95 are preferably concealed by a tube
compression assembly 101. The tube compression assembly 101 is
received on the tube section 59 of the rod assembly 55. As best
seen in FIG. 5, the tube compression assembly 101 facilitates
placing the tube section 59 in fluid communication with a fitting,
detector, column or conduit, generally designated by the numeral
103. The tube compression assembly 101 is made of rigid materials,
such as plastic and metals.
[0057] Tube compression assembly 101 comprises a ferrule 103 and a
ferrule fitting 105. The ferrule fitting 105 is rotatably slidably
received on the tube section 59 extending from the compression
fitting 57 to allow movement. The ferrule fitting 105 moves axially
along the tube section 59 as the ferrule fitting 105 is tightened
against the ferrule 103. As best seen in FIG. 5, the fitting,
detector, column or conduit, generally designated by the numeral
133, has ferrule fitting receiving surfaces 109a which cooperate
with threaded surfaces 109b on the ferrule fitting 105, to allow
the ferrule fitting 105 to be tightened. Ferrule 103 is slidably
received on tube section 59 to allow ferrule 103 to compress
against a ferrule receiving surface 107 fitting, detector, column
or conduit, generally designated by the numeral 133. As the ferrule
fitting 105 is tightened, the ferrule 103 is sealed under
compression against the tube section 59 and the ferrule receiving
surface 107.
[0058] Turning now to FIGS. 1 and 4, when the device 11 is not
fitted to a fitting, detector, column or conduit, generally
designated by the numeral 133, an "O" ring 111 is fitted to the
tube section 59 to retain the ferrule fitting 101 and the ferrule
103 in place. In use, the "O" ring 111 is removed.
[0059] The ferrule fitting 105 has a ferrule fitting interior
surface 113, a ferrule fitting exterior surface 115, a ferrule
fitting first opening 117 and a ferrule fitting second opening 119.
The ferrule fitting interior surface 113 defines a ferrule fitting
tube channel 121, as best seen in FIG. 1, between the ferrule
fitting first opening 117 and the ferrule fitting second opening
119. The ferrule fitting tube channel 121 has a ferrule fitting
narrow section 123a and a ferrule fitting expanded section 123b.
The ferrule fitting narrow section 123a receives the tube section
59.
[0060] As best seen in FIG. 1, the ferrule fitting expanded section
123b receives and conceals the compression fitting turning surfaces
95. Thus, the user is discouraged from separating the body 13 from
the compression fitting 57.
[0061] The ferrule fitting 105 has a male end 125 at the ferrule
fitting second opening 119. The ferrule fitting 105 has a ferrule
fitting rim 127 for receiving the ferrule 103.
[0062] Turning now to FIG. 5, the second body end 33, the body 13
has second end attachment means for affixing, in fluid
communication to an analytical column, fitting, detector or a
conduit, generally designated by the numeral 131. Those skilled in
the art will recognize that the device 11 may accommodate flow in
either direction and the use of the terms "analytical column,
fitting, detector or a conduit" is intended to encompass the use of
the device 11 with a flow in either direction.
[0063] Turning again to FIG. 1, second end attachment means
comprise connection section 39d of passage 37. Connection section
39d has threads 141 for receiving cooperating threads of a column,
or a detector or conduit, or a further fitting, generally
designated by the numeral 131. Such cooperating threads are common
in ferrule compression fittings and the like. For guard column
applications, the total volume, from the narrows of passage 21 at
end 31 to the end of tube 59 is approximately 20 to 22 microliters
of which 9 to 10 microliters are occupied by a particulate bed 15
for a total device volume of approximately 10 to 12
microliters.
[0064] A further embodiment of the present invention comprises a
method of separating compounds in a solution from each other or
undesired components of the solution. The method comprises the step
of providing a device 11 having a body 13, a separation media 15,
and at least one frit element 17a or 17b as previously described.
The method comprises the further step of flowing solutions through
the device 11 to separate compounds from each other or from
particulates.
[0065] Referring now to FIG. 5, a further embodiment of the present
invention comprises an apparatus, generally designated by the
numeral 151. The apparatus 151 comprises a device 11 as previously
described and one or more instruments selected from the group
comprising a high performance chromatography pump, detector and
column, generally designated by the numerals 103 or 131.
[0066] Thus, embodiments of the present invention have been
describe with respect to preferred configurations and steps with
the understanding that the invention can be modified and altered
without departing from the teaching herein. Thus, the present
invention should not be limited to the precise details herein but
should encompass the subject matter of the claims that follow and
their equivalents.
* * * * *