U.S. patent number RE29,725 [Application Number 05/035,438] was granted by the patent office on 1978-08-08 for analytical test pack and process for analysis.
This patent grant is currently assigned to E. I. du Pont de Nemours and Company. Invention is credited to Donald R. Johnson, Richard G. Nadeau, Gerrit Nieuweboer, William L. Truett.
United States Patent |
RE29,725 |
Johnson , et al. |
August 8, 1978 |
Analytical test pack and process for analysis
Abstract
Performing analytical tests more easily, quickly and accurately
by using a specially designed pouch-like container of pliable
material. The container has within it a plurality of compartments,
each compartment being capable of containing a different reagent
and each compartment also being capable of releasing its contained
reagent, independently of any other reagents present in the other
compartments, into the area of the container not occupied by
compartments. This latter area of the container is also adapted to
receive the test sample for reaction with any single reagent or any
combination of reagents released from the compartments.
Inventors: |
Johnson; Donald R. (Wilmington,
DE), Nadeau; Richard G. (Claymont, DE), Nieuweboer;
Gerrit (Claymont, DE), Truett; William L. (Blackwood,
NJ) |
Assignee: |
E. I. du Pont de Nemours and
Company (Wilmington, DE)
|
Family
ID: |
26712127 |
Appl.
No.: |
05/035,438 |
Filed: |
May 7, 1970 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
Reissue of: |
545494 |
Apr 26, 1966 |
03476515 |
Nov 4, 1969 |
|
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Current U.S.
Class: |
435/12; 206/219;
356/246; 356/409; 422/562; 422/915; 422/940; 435/14; 435/16;
435/287.6; 435/288.5; 435/810; 436/108; 436/165; 436/95 |
Current CPC
Class: |
B01L
3/502 (20130101); B01L 3/5453 (20130101); C12Q
1/00 (20130101); G01N 21/03 (20130101); G01N
21/253 (20130101); G01N 33/528 (20130101); G01N
35/00 (20130101); G01N 35/02 (20130101); B01L
3/505 (20130101); B01L 2200/16 (20130101); B01L
2300/0867 (20130101); B01L 2400/0683 (20130101); G01N
35/1079 (20130101); G01N 2035/0436 (20130101); Y10T
436/144444 (20150115); Y10T 436/171538 (20150115) |
Current International
Class: |
B01L
3/14 (20060101); B01L 3/00 (20060101); C12Q
1/00 (20060101); G01N 21/25 (20060101); G01N
33/52 (20060101); G01N 21/03 (20060101); G01N
35/00 (20060101); G01N 33/487 (20060101); G01N
35/02 (20060101); G01N 35/04 (20060101); G01N
35/10 (20060101); G01N 033/16 (); G01N
021/24 () |
Field of
Search: |
;23/23B,23R,253R,259
;356/246,180 ;206/219,459,498 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Serwin; R.E.
Claims
What is claimed is:
1. An analytical test pack consisting essentially of a pouch-like
container of pliable material; said container having a plurality of
compartments, the compartments occupying less than the total volume
of said container to leave a reaction chamber, the compartments
being adapted to be charged with predetermined quantities of
testing reagents and each compartment being further adapted to
release said reagents independently of any other reagents present
in the other compartments into the reaction chamber; and means
communicating with said reaction chamber for introducing the test
sample into said reaction chamber, said means being adapted to
prevent backflow of said test sample after its introduction into
the reaction chamber.
2. An analytical test pack as in claim 1 wherein information for
identifying and for processing said pack are affixed to said
pack.
3. An analytical test pack composed of two opposed layers of
pliable polymeric material of substantially equal dimensions; the
first of said layers having at least one recess therein, said
recess occupying less than the total area of first first layer; a
predetermined amount of analytical reagent in said recess; the
second layer bonded to said first layer in the area about said
recess, the bonded area being adapted to be ruptured sufficiently
to release reagent from said recess independently of any other
reagent present in any other recess upon the application of
pressure into the space between said two opposed layers not
occupied by said recess; means communicating with the space between
said two opposed layers not occupied by said recess for introducing
the material to be tested into the said space; the second layer
being further bonded to said first layer in an area remote from
said recess, the further bonded area being substantially permanent,
to provide an enclosed reaction chamber communicating with sid
means for introducing the material to be tested.
4. An analytical test pack as in claim 3 wherein said means for
introducing the material to be tested comprises a substantially
rigid header bonded to at least one of said opposed layers of
polymeric material, said header having a substantially cylindrical
channel disposed laterally therein and at least one opening, said
opening communicating with said channel and with an opening in said
layer of polymeric material, said channel adapted to receive a
cartridge in snug-fitting relationship, said cartridge having an
opening communicating with the opening in the header.
5. An analytical test pack as in claim 3 wherein information for
identifying and for processing said pack are affixed to said pack.
6. An analytical test pack composed of two opposed layers of
pliable polymeric material of substantially equal dimensions; the
first of said layers having a plurality of recesses therein, said
recesses occupying less than the total area of said first layer;
predetermined amounts of analytical reagents in at least two of
said recesses; the second layer bonded to said first layer in areas
about each of said recesses, the bonded areas being adapted to be
ruptured sufficiently to release said reagents from each of said
recesses independently of each other and independently of any
reagents in any other recesses upon the application of pressure
into the space between said two opposed layers not occupied by said
recesses; means communicating with the space between said two
opposed layers not occupied by said recesses for introducing the
material to be tested into said space; the second layer being
further bonded to said first layer in an area remote from said
recesses, the further bonded area being substantially permanent, to
provide an enclosed reaction chamber communicating with said means
for introducing the material to be tested.
An analytical test pack as in claim 6 wherein information for
identifying and for processing said pack are affixed to said pack.
8. An analytical test pack as in claim 6 wherein said means for
introducing the material to be tested comprises a substantially
rigid header bonded to at least one of said opposed layers of
polymeric material, said header having a substantially cylindrical
channel disposed laterally therein and at least one opening, said
opening communicating with said channel and with an opening in said
layer of polymeric material, said channel adapted to receive a
cartridge in snug-fitting relationship, said cartridge having
an
opening communicating with the opening in the header. 9. An
analytical test pack as in claim 8 wherein said cartridge contains
means for removing
undesirable components from the material to be tested. 10. An
analytical test pack as in claim 8 wherein information for
identifying and for
processing said pack are affixed to said header. 11. A process for
preparing an analytical test pack which comrises forming a
plurality of depressions in a sheet of polymeric material, said
depressions occupying less than the total areas of the sheet;
placing pre-measured quantities of reagents in at least one of said
depressions; placing a second sheet having substantially the same
dimensions as the first sheet over the first sheet; bonding the
second sheet to the first sheet substantially along the outer
periphery of the sheets to provide a reaction chamber between the
sheets; bonding the second sheet to the first sheet in areas about
each of said reagent-containing depressions, said bonded areas
being adapted to be ruptured sufficiently to release said reagents
from each of said depressions independently of any other reagents
present in the other
depressions into the reaction chamber. 12. A process for preparing
an analytical test pack which comprises forming a plurality of
depressions in a sheet of polymeric material, said depressions
occupying less than the total area of the sheet; placing
pre-measured quantities of reagents in at least one of said
depressions; placing a second sheet having substantially the same
dimensions as the first sheet over the first sheet; bonding the
second sheet to the first sheet in the areas about each of said
depressions, said bonded areas being adapted to be ruptured
sufficiently to release said reagents from each depression
independently of any other reagents present in the other
depressions into the remaining space between said sheets; bonding
the second sheet to the first sheet substantially along the outer
periphery of the sheets; bonding a substantially rigid header to
said sheets, said header having an inlet port communicating with an
opening in the sheet adjacent to said header; and bonding said
header to said sheet adjacent thereto in the area surrounding the
opening in said
sheet. 13. A method of analyzing a test sample in a reaction
chamber provided by the space between two sheets of pliable
material bonded together at their outer peripheries, the space
between the sheets also containing at least one reagent, each
reagent enclosed by an area in which the two sheets are bonded to
each other, comprising introducing the test sample into the
reaction chamber; applying pressure to at least one of the sheets
in an area adjacent at least one of said reagents sufficient to
rupture the bonded area enclosing said reagent to release said
reagent into said reaction chamber independently of any other
reagents in other bonded areas whereby any single reagent or
combination of reagents may be released; applying a pulsating
pressure to the sheets encompassing the reaction chamber to mix
said test sample and said reagent; and reading out
the result of the reaction between said reagent and said test
sample. 14. A method as in claim 13 wherein said reaction chamber
is formed into an analytical cell and the result of the reaction is
read out in said cell. .Iadd. 15. An analytic test pack comprising
a container having at least one wall of pliable material; said
container having at least two compartments occupying less than the
total volume of said container and a reaction chamber, the
compartments being adapted to be charged with predetermined
quantities of testing reagents and each compartment being further
adapted to release said reagents independently of any other
reagents present in the other compartments into the reaction
chamber; and means communicating with said reaction chamber for
introducing a test sample into said reaction chamber.
.Iaddend..Iadd. 16. The analytic test pack of claim 15 wherein at
least a portion of the walls of said reaction chamber are
sufficiently optically transparent so that said reaction chamber
can be utilized as an optical cell for optical analysis.
.Iaddend..Iadd. 17. The analytic test pack of claim 15 wherein said
reaction chamber comprises at least one compartment and wherein
each of said compartments has at least one wall of a pliable
polymeric material. .Iaddend..Iadd. 18. The analytic test pack of
claim 17 wherein at least a portion of the walls of each of said
compartments are sufficiently optically transparent so that each of
said compartments can be utilized as an optical cell for optical
analysis. .Iaddend. .Iadd.19. A method of analyzing a test sample
comprising: providing an analytic test pack having a reaction
chamber, at least one wall of which is of pliable material, and at
least one reagent compartment containing reagents and separated
from said reaction chamber; introducing the test sample into said
reaction chamber; releasing at least one reagent contained in at
least one reagent compartment into said reaction chamber,
independently of any other reagents in other reagent compartments,
whereby any single reagent or combination of reagents may be
introduced into said reaction chamber; mixing said test sample and
said reagent; and reading out the result of the reaction between
said reagent and said test sample. .Iaddend. .Iadd. 20. The method
of claim 19 wherein at least a portion of the walls of said
reaction chamber are optically transparent and wherein the step of
reading out the result of the reaction between said reagent and
said test sample is accomplished by monitoring the optical
properties of the reaction mixture by directing electromagnetic
radiation through the reaction mixture while it is in the test
pack, and generating a signal in response to the transmitted
radiation, and processing said signal to produce an analytical
result. .Iaddend. .Iadd. 21. The method of claim 19 wherein the
step of releasing reagents into said reaction chamber takes place
by first releasing at least one reagent into said reaction chamber,
and, then, after a period of time, releasing at least one other
reagent into said reaction chamber. .Iaddend..Iadd. 22. The method
of claim 19 wherein said reaction chamber is divided into two
compartments, wherein each of said compartments is conditioned
differently, and wherein the step of reading out the reaction
between said reagents and said test sample is accomplished
differentially. .Iaddend. .Iadd. 23. The method of analyzing a test
sample comprising providing a disposable test pack having a
reaction compartment and at least one reagent stored within said
test pack but separated from said reaction compartment, at least a
portion of the test pack being sufficiently optically transparent
so that the test pack can be utilized as an optical cell for
optical analysis, the test pack carrying information for
identifying and for processing the test pack, adding a measured
quantity of a sample to the reaction compartment, adding at least
one reagent stored within the disposable container to the reaction
compartment to form a reaction mixture, incubating said reaction
mixture within said test pack for a period of time sufficient to
bring the reaction mixture to the desired state for analysis, and
monitoring at least one of the optical properties of said reaction
mixture while it is within said test pack by directing
electromagnetic radiation through said reaction mixture, and
generating a signal in response to the transmitted radiation, and
processing said signal to produce an analytical result. .Iaddend.
.Iadd. 24. The method of claim 23 wherein a plurality of stored
reagents are added to the reaction compartment. .Iaddend..Iadd. 25.
The method of claim 23 wherein a plurality of stored reagents are
added each at different times to the reaction compartment.
.Iaddend. .Iadd. 26. The method of claim 23 further including
mixing the measured quantity of sample after each reagent is added
thereto. .Iaddend..Iadd. 27. The method of analyzing a test sample
comprising providing a disposable test pack having a reaction
compartment and a plurality of reagents stored within said test
pack but separated from said reaction compartment, at least a
portion of test pack being sufficiently optically transparent so
that the test pack can be utilized as an optical cell for optical
analysis, adding a measured quantity of a sample to the reaction
compartment, adding at least one reagent stored within the test
pack to the reaction compartment to form a reaction mixture,
incubating said reaction mixture within said reaction compartment,
adding at least one further reagent stored within the disposable
container to the reaction mixture, and monitoring at least one of
the optical properties of said reaction mixture while it is within
said test pack by directing electromagnetic radiation through said
reaction mixture, and generating a signal in response to the
transmitted radiation, and processing said signal to produce an
analytical result. .Iaddend..Iadd. 28. A disposable test pack
comprising: a reaction compartment, for the mixing of materials
added thereto; a storage section having a plurality of separate
reagent storage chambers, said reagent storage chambers being
adapted to be charged with predetermined quantities of reagents,
each of said reagent storage chambers being further adapted to
release said reagents independently of any other reagents present
in other reagent storage chambers into said reaction compartment;
and means communicating with said reaction compartment for
introducing a sample into said reaction compartment.
.Iaddend..Iadd. 29. A disposable test pack comprising: a reaction
compartment for the mixing of materials added thereto; a storage
section having a plurality of separate reagent storage chambers,
said reagent storage chambers being adapted to be charged with
predetermined quantities of reagents, each of said reagent storage
chambers being further adapted to release said reagents
independently of any other reagents present in other reagent
storage chambers into said reaction compartment; and means
communicating with said reaction compartment for introducing a
sample into said reaction compartment; at least a portion of said
test pack being sufficiently optically transparent so that said
test pack can be utilized as an optical cell for optical analysis.
.Iaddend..Iadd. 30. The disposable test pack of claim 30 wherein
said test pack comprises a plurality of reaction compartments.
.Iaddend..Iadd. 31. The disposable test pack of claim 30 wherein at
least a portion of said reaction compartment is made from a pliable
material. .Iaddend..Iadd. 32. The disposable test pack of claim 30
having data stored thereon. .Iaddend..Iadd. 33. The disposable test
pack of claim 30 wherein said storage section comprises a layer
having a plurality of reagent-storing chambers formed therein.
.Iaddend. .Iadd. 34. The method of analyzing a test sample in a
disposable test pack having a reaction compartment, at least one
reagent stored within said disposable container but separated from
said reaction compartment, and at least a portion of said test pack
being sufficiently transparent so that the reaction compartment can
be utilized as an optical cell for optical analysis, said method
comprising adding a measured quantity of a sample to the reaction
compartment, adding at least one reagent stored within the test
pack to said reaction compartment, and monitoring at least one of
the optical properties of said reaction mixture while it is within
said test pack, said monitoring including defining an optical path
through the reaction mixture in the test pack by cooperation of
external optical path-defining means with the sufficiently flexible
walls of said test pack and passing a beam of electromagnetic
radiation through said reaction mixture along said optical path.
.Iaddend..Iadd. 35. The method of analyzing a test sample
comprising providing a disposable test pack having a reaction
compartment and at least one reagent stored within said disposable
test pack but separated from said reaction compartment, the test
pack carrying information for identifying and for processing the
test pack, adding a measured quantity of a sample to the reaction
compartment, adding a reagent stored within the test pack to the
sample to form a reaction mixture, incubating said reaction mixture
within said test pack for a period of time sufficient to bring the
reaction mixture to the desired state for analysis, and reading out
the result of the reaction between the reagent and the test sample
while the reaction mixture is within said test pack. .Iaddend.
Description
This invention relates to novel testing containers, processes for
making them, and the processes of using such containers to carry
out analytical procedures.
Among the many problems facing the biomedical field is the lack of
assurance that the results of analytical tests are error-free.
Although these analytical tests are extremely important, and
critical decisions relating to patient treatment must be based upon
the results of such tests, the procedures leave much to be desired
from the standpoint of being free of operator errors. The
procedures are usually repetitive, routine, time-consuming and
dull. Hence, they are usually performed by technicians whose slight
errors in weighing reagents, in mixing reactants, in timing the
reactions, etc., can and sometimes do produce disastrous
results.
The object of this invention is to provide the means for performing
analytical tests more easily, more quickly and accurately even by
those without any significant technical training while minimizing
the possibility of operator errors. Other objects will appear
hereinafter.
Although the invention will be described primarily for its
application in the biomedical field, the invention is useful for
the performance of a variety of chemical and biological tests.
Thus, the subject matter of the invention will find use in
pharmaceutical laboratories, agricultural laboratories, etc., as
well as in general chemical and biological laboratories.
The objects are accomplished by providing an analytical test pack
composed of a pouch-like container of flexible (pliable) polymeric
material, preferably of transparent or transluscent, thermoplastic
material, the container being divided into, or containing a
plurality of small compartments or chambers; the plurality of small
compartments occupying less than the total volume of the container
to leave a reaction chamber, the small compartments being adapted
to be charged with predetermined amounts of testing reagents and
each adapted further to be capable of releasing these reagents
independently into the reaction chamber, usually upon the exertion
of suitable energy, e.g., pressure; and means communicating with
the reaction chamber for introducing the material to be tested, the
test sample, into the reaction chamber, the introducing means being
adapted to prevent backflow of the test sample after its
introduction into the reaction chamber.
In the broadest sense, one process for preparing the analytical
test pack comprises forming at least one depression or recess,
preferably a plurality of depressions or recesses, in a
substantially flat sheet of a polymeric film, the depressions
occupying less than the total area of the sheet; placing
premeasured quantities of reagents in the depressions; placing a
second sheet usually having substantially the same dimensions as
the first sheet over the first sheet, the second sheet preferably
being heat sealable to the first sheet; bonding the second sheet to
the first sheet substantially along the outer periphery of the
sheets to provide a reaction chamber between the sheets; bonding
the two sheets to one another around the depression(s) to fix the
location of the reagent(s) in a manner such that the bonded areas
are rupturable so that they may be unbonded upon the exertion of
suitable force to release the reagents from the depressions into
the reaction chamber. It should be understood that the means for
introducing the material to be treated into the reaction chamber is
preferably built into the test pack as will be shown in the
subsequent description. However, it is possible to use a hypodermic
needle inserted carefully into the wall to introduce the material
to be tested and to reseal the point of insertion after withdrawing
the needle.
The process of using the analytical test pack involves employing
premeasured quantities of the analytical reagents in the various
recesses, bonding the areas around the reagents and introducing the
sample to be analyzed through an inlet into the reaction chamber;
applying pressure to at least one sheet in the area adjacent to at
least one reagent to rupture the bonded area around the reagent to
release the reagent from the recess into the reaction chamber;
mixing the reagent by pulsating the sheets encompassing the
reaction chamber and reading out the result of the reaction between
the reagent and the test sample.
"Reading out" may be accomplished by measuring the spectral
characteristics with an appropriate photometer, e.g.,
spectrophotometer, fluorimeter, etc., or measuring the thermal
properties, the chemical properties, the physical properties, or
the electrical or electrochemical properties, e.g., dielectric
constant, conductivity, diffusion current, or electrochemical
potential etc. It should be understood that, where appropriate, the
sensors for certain measurements can be incorporated in the test
pack during construction. For example, electrodes for conductivity
or electrochemical measurements, thermocouples or thermistors for
thermal measurements, etc., can be incorporated in the test pack
during construction. "Reading out" is preferably accomplished by
forming the reaction chamber into a suitable optical cell and
measuring spectral characteristics.
In using the test pack, advantage may be taken of differential
measurement techniques. This may be accomplished by dividing the
reaction chamber into two portions by sealing it accordingly and
subjecting the two portions to different conditions. "Read out" is
then accomplished by determining any of the above properties in a
differential manner.
The test packs, their preparation and their use in analysis will be
more clearly understood by referring to the drawings and the
description that follows.
In the drawing:
FIG. 1 is a view, in perspective, of one embodiment of an
analytical test pack of this invention;
FIGS. 1A-1C depict the steps in forming the test pack illustrated
in FIG. 1;
FIGS. 2-4 are other embodiments of test packs that utilize the
principles of this invention; and
FIG. 5 is a schematic illustration of an automatic apparatus that
uses the preferred analytical test pack.
PREPARATION OF TEST PACK
The preferred test pack is shown in FIG. 1. Reference is made first
to FIG. 1A in describing its preparation. The first step involves
forming a plurality of circular depressions or recesses 10 in
substantially side-by-side relationship in a base sheet of
impervious pliable or flexible polymeric material 11. The sheet is
preferably transparent, thermoplastic and selected from any of the
following materials; polymers of olefins, e.g., ethylene, propylene
and copolymers with vinyl acetate, etc., halogenated polymers,
e.g., polymers of vinyl chloride, vinylidene chloride and
copolymers with vinyl acetate, rubber hydrochloride, vinyl fluoride
polymers, etc., polyesters, e.g., polyethylene terephthalate,
ionomer resins, etc. or laminates thereof or laminates with metal
foils. Preferred materials are disclosed in U.S. Patent application
Ser. No. 271,477, filed Apr. 8, 1963 to R. W. Rees, now U.S. Pat.
No. 3,264,272. They are the ionic copolymers of alpha-olefins
(ethylene) and alpha, beta-ethylenicaly unsaturated carboxylic
acids of 3-8 carbon atoms having 10-90% of the carboxylic acid
groups ionized by being neutralized with metal ions. The size of
the sheet may be anywhere from 1 inch .times. 1 inch, 3 inch
.times. 4 inch, etc. to any conveniently handled size. The recesses
10 are most easily formed by bringing an appropriate die, heated or
otherwise, into contact with the base sheet and applying pressure.
It should be understood that vacuum forming may also be used for
forming the recesses.
The next step involves placing solid or liquid reagents in the
recesses 10. The simplest procedure is to place tablets in the
recesses. The reagents may also be added as liquids followed by
freeze-drying, if desired, in situ. Specific representative
materials for specific analytical tests will be disclosed in the
subsequent examples.
After the reagents have been placed in the recesses, a second sheet
12 corresponding to the first or base sheet in size and usually in
composition is placed over the first sheet. Heat and pressure are
then applied to the areas a surrounding the pods of reagent with a
conventional heat sealing die or using an impulse heat sealer.
However, the bonded or sealed areas are relatively narrow and/or
the heat input is controlled carefully to avoid permanently sealing
these areas. Specifically, the temperature, pressure, and dwell
time may be controlled to provide seals that can be later ruptured
by the application of pressure to liquid in the chamber between the
two sheets exterior to the recesses, the liquid serving to peel the
seals hydraulically. Alternatively, adhesives or other forms of
bonding may be used, provided that rupturable bonds, as disclosed
previously, are formed in these areas. Heat and pressure are then
applied to area b to provide permanent bonding at the peripheries
of sheets 11 and 12 and to form a reaction chamber 28 between them.
It will be noted that a small area c at one edge is left
unbonded.
The rigid header 13 having a substantially cylindrical channel 14
disposed laterally therein and a single small opening 15 from one
side of the header communicating with the channel, is then placed
under the base sheet 11 in a manner shown in FIG. 1B such that the
opening 15 is directly beneath the opening 17 in the base sheet 11.
Two additional openings, 16a and 16b, will be noted on the face of
header 13 opposite to the face in which opening 15 is located. This
face of the header may also carry information for identifying and
using the test pack.
Heat and pressure are then applied to the sheet 11 and the header
13 in the area d to bond the base sheet 11 to the header around the
opening 17. After this step, heat and pressure are applied along
area e across the upper edges of the two sheets and the header to
bond the sheets to the header 13 and to form the test pack shown in
FIG. 1. It will be noted that the test pack has been reversed in
FIG. 1 so that the header 13 and the base sheet 11 are over sheet
12.
To complete the test pack, the cartridge shown in FIG. 1C is
inserted into the channel 14. The cartridge is composed of a length
of relatively stiff polymeric tubing (preferably of polypropylene)
18; a stopper 19, usually of rubber, designed to provide free area
shown at 27; and a combined stopper and valve 20. The stopper valve
20 is designed with a passage 21 to provide communication from
within the tube 18 through the passage 21 and through the opening
15 in the header 13 and the opening 17 in the base sheet 11 into
the reaction chamber between the sheets 11 and 12. A partition 23
separates the channel 21 from the interior of the tube 18. When the
partition 23 is made of an impervious material, liquid may be
delivered into the reaction chamber by injecting it into channel 21
and thence through the passage previously described by inserting an
appropriate injection means such as a hypodermic needle through
opening 16a in the header 13. When the partition is made of a
porous material such as a screen or filter, liquid may be delivered
into the reaction chamber through the interior of the tube 18 and
the channel 21 and thence through the passage previously described
by inserting an appropriate injection means such as a hypodermic
needle into the free area 27 of stopper 19 through oepning 16b in
the header 13. In either case, after the delivery of liquid into
the reaction chamber is complete, the stopper-cartridge assembly is
moved to the right a sufficient amount to close the opening 15 to
prevent backflow of the test sample.
The advantages of the cartridge are readily apparent. Besides
providing an efficient and accurate means for delivering liquid,
e.g., the liquid sample, into the test pack, the cartridge provides
an area for the possible location of analytical aids. Thus, an ion
exchange resin can be placed within the tube 18 so that the ions
can be removed or the pH of a sample can be altered as the sample
flows through the tube and into the chamber. A filter bed, a filter
screen, or a gel filtration material, e.g., "Sephadex" dextran gel,
"Biogel" polyacrylamide gel, etc., can also be placed within the
tube. Alternatively, combinations of the above with or without
other analytical aids, mixed or in sequence, may be included in the
tube 18.
FIGS. 2, 3, and 4 represent less preferred embodiments of the
analytical test pack of the invention. Instead of using a header as
the means for providing the inlet to the reaction chamber, these
embodiments utilize a flexible tube 22 conjointly sealed with the
two sheets forming the container to provide a resealable inlet.
Specifically, in FIG. 2, a plurality of depressions 10 are formed
in at least one of the sheets 11. The reagents are placed in the
depressions. The flexible tube 22, usually of the same material as
the sheets, is placed so that it intersects one edge of the sheet.
Sheet 12 is then placed over sheet 11 and the sheets are joined
along the edge by heat sealing or adhesion without sealing the
opening in the tube 22. This may be accomplished by placing a rigid
wire or rod within the opening during heat sealing and removing it
after sealing. The area surrounding the depressions 10 in sheet 11
are also joined to sheet 12 to isolate each reagent. Heat sealing
is preferred for this purpose, although any method may be used to
provide a seal that will prevent release of the reagent until the
seals are subsequently ruptured.
In FIG. 3, two sheets 11 and 12 are joined along three edge areas
a, b, and c by heat sealing or adhesion. They are also joined along
the longitudinal areas represented by d. After the reagents are
placed in the spaces 26, they are sealed in by a breakable seal
along the area represented by e. The flexible tube 22 is then
placed between the two sheets 11 and 12 so as to intersect the
unjoined edge f. Thereafter, the sheets are joined along this last
mentioned edge, the process of joining also serving to preserve the
opening in the tube 22 as described with reference to FIG. 2.
The container shown in FIG. 4 employs separate lengths 24 of the
container in which to place the reagents. For this embodiment,
breakable seals or clips 25 can be used to prevent release of the
reagents until desired. In all other respects, this container may
be prepared substantially as the container of FIG. 3.
PROCESS OF USING THE TEST PACK
A process for using the preferred analytical test pack is shown in
FIG. 5. A series of sample containers are affixed to cards at the
input; a test pack for each analysis to be performed on the sample
is placed with the container; and the test set (the sample
container and test packs) is routed accordingly.
At station 1, a measured quantity of the sample is introduced into
the reaction chamber of the test pack. Optionally, a diluent may
also be added at this point. This step is most easily performed by
using a hypodermic needle to withdraw sample from a sample cup and
to inject it into the cartridge of the pack shown in FIG. 1. This
can be done manually or mechanically. If the sample is suitable for
analysis as received, it is injected into channel 21 through the
opening 16a in the header 13, and thence into the reaction chamber
as previously described. If the sample requires preliminary
treatment, e.g., filtration, removal of interfering substances,
etc., it is injected into the free area within stopper 19, through
opening 16b. The sample then passes through a suitably filled
interior of tube 18, the partition 23 and channel 21 before passing
into the reaction chamber.
At station 2, a selected pod or pods containing reagents for the
analysis are released into the reaction chamber and mixed with its
contents. Manually, this can be done by applying suitable force to
open the "breakable" seals and, thus to release the reagents into
the reaction chamber. In a mechanical operation, this is most
easily done by first protecting those pods which are not to be
opened with a ring of metal or other rigid material. A flat metal
surface behind the pods and a metal surface containing recesses to
enclose the pods to be protected represent the simplest device.
Thereafter, by applying pressure to the remainder of the bag, the
hydraulic force of the liquid in the pack can be used to open the
"breakable" seals around the unprotected pods. In this manner, the
reagents are released into the reaction chamber. By the application
and release of a light, pulsing force on the liquid, the reagents
are mixed thoroughly with the contents of the reaction chamber.
Station 3 may be used if a waiting period is necessary before
releasing one or more additional reagents at station 4. Station 3
may also be used to provide time for obtaining a blank reaction
based on the activities at station 2 before proceding to station 4.
Since station 4 is substantially identical to station 2, either of
these stations may be used if only one addition of reagent(s) is
contemplated. The choice of station depends upon whether a delay at
station 3 is desired prior or subsequent to the single
addition.
Station 5 is the readout station. If the result is to be read out
photometrically, then means are provided to clamp the pack in a
position where electromagnetic radiation, e.g., visible,
ultraviolet, or infrared can be directed through the contents of
the reaction chamber and the transmitted radiation can be directed
on to an appropriate detector. The measurement obtained usually
provides the absorption or rate of change of absorption of the
contents of the chamber. Optionally, the signal from the detector
can be amplified and processed with the result being printed on the
card affixed to the original sample container at the "digital
printer" location. Thereafter, the card and the spent test pack(s)
are fed as a test set to the output station.
The process of using the test pack provides many advantages. For
example, any test or tests for which test packs are available may
be performed in any order or at any time by relatively unskilled
personnel without modifying the experimental apparatus. Reagents
and other materials can be kept in their most stable form until
immediately before use and little or no operator effort is required
to prepare them for use. Materials and methods can be made uniform
and can be controlled for optimum performance to insure accuracy of
the test irrespective of the operator or the location. Positive
identification of the sample and the test can be provided on the
print-out device to further minimize the opportunity for operator
error. New and sophisticated tests may be performed with a minimum
of operator training. Since the test packs are disposable, there is
no investment in glassware nor is there any necessity for cleaning.
The possibility of contaminating the reagents or the test equipment
is minimized. It will also be apparent that the waste of expensive
reagents incurred when usual laboratory batches are incompletely
used is minimized.
Additional advantages will be apparent from the following examples
illustrating the utility of the invention. These examples, being
merely illustrative, should not be considered to limit the scope of
the invention.
EXAMPLE 1
In this example, the testing procedure for determining blood urea
nitrogen as described in U.S. patent application Ser. No. 502,596
filed Oct. 22, 1965 to R. G. Nadeau, may be performed.
A measured amount of 1-cysteine hydrochloride (1.575 milligrams) is
placed in compartment No. 1 of the test pack illustrated in FIG. 1.
Measured amounts of the monosodium salt of alpha-ketoglutaric acid
(3.54 milligrams) and the disodium salt of
dihydro-beta-diphosphopyridinenucleotide (1.01 milligrams) are
placed in compartment No. 2 of the test pack. A measured amount
(4.5 units) of alpha-glutamic dehydrogenase in 50% glycerol is
placed in compartment No. 3. A measured amount (0.5 unit) of urease
is placed in compartment No. 4.
The test sample of blood serum is first introduced into the chamber
by injection into channel 21 of the header of the test pack of FIG.
1 as described on page 8. A phosphate buffer is then introduced
into the reaction chamber. Pressure is applied to rupture the seals
surrounding compartments Nos. 1, 2, and 3 to release their contents
and mix them with the test sample. After a suitable delay, the seal
surrounding compartment No. 4 is ruptured to release urease and the
results are "read out" as described in Ser. No. 502,596 by
determining absorbance or rate of change of absorbance using light
at 340 millimicrons to provide the concentration of urea in the
test sample.
EXAMPLE 2
In this example, a test pack similar to that shown in FIG. 1 is
used, the pack containing only four reagent compartments. In the
first reagent compartment is placed 10.0 milligrams of
beta-nicotinamide adenine dinucleotide disodium salt (oxidized
form), 0.25 milligram of phenazine methosulfate, and 0.2 milligram
of 2,6-dichlorophenol indophenol. The second, third and fourth
compartments contain measured amounts of 1-lactic acid, 1-malic
acid and alpha-hydroxybutyric acid, respectively. The main reaction
chamber contains a liquid buffer composition of sodium hydrogen
phosphate.
An exact quantity of blood serum is introduced into the reaction
chamber by injection into channel 21 of the header of the test pack
of FIG. 1 as described on page 8. A phosphate buffer as a diluent
is then injected into channel 21 and fed into the reaction chamber.
The seal surrounding the first reagent compartment is ruptured to
release the nicotinamide adenine dinucleotide, phenazine
methosulfate and dichlorophenol indophenol. These reagents are
mixed with the serum and the buffer solution in the main reaction
chamber by applying pressure in a pulsating manner to the chamber.
Thereafter, depending upon which of three dehydrogenase
determinations (lactic acid dehydrogenase, malic acid dehydrogenase
or alpha-hydroxybutyric acid dehydrogenase) is desired, the seal
around one of the remaining three reagent compartments is
ruptured.
The contents are mixed with the solution in the reaction chamber by
again applying a pulsating pressure and the result is "read out" in
a manner similar to that described in Ser. No. 502,596 by
determining absorbance or change in absorbance using light at 610
millimicrons to provide the concentration of the particular
dehydrogenase. Alternatively, the main reaction chamber and its
contents may be divided into two sections by the application of an
impulse sealer. One section may be heated to about 37.degree. C.
while the other section may be cooled to 5.degree. C. After a
suitable period, the two sections may then be read differentially
using a spectrophotometer. The concentration of the particular
enzyme in the test sample is determined from the differential
absorbance measurement.
EXAMPLE 3
This example describes a testing procedure for determining
glucose.
A measured amount of 3,3' dimethoxybenzidine dihydrochloride (0.25
milligram) is placed in compartment No. 1 of the test pack
illustrated in FIG. 1. A measured amount of peroxidase (0.01
milligram or 1.1 units) is placed in compartment No. 2 of the test
pack. Lastly, a measured amount of glucose oxidase (0.125 milligram
or 16.25 units) is placed in compartment No. 3.
A test sample of blood serum, or other fluid in which glucose is
present, is introduced into the chamber. A phosphate buffer is then
introduced into the reaction chamber as in Example 2. A force is
applied to rupture the seals surrounding compartments Nos. 1 and 2
to release the reagents and mix them with the contents of the
reaction chamber. After thorough mixing, the seal surrounding
compartment No. 3 is ruptured to release the glucose oxidase and
the results are "read out" as in Example 1 by determining the
absorbance or rate of change of absorbance using light as 437
millimicrons.
EXAMPLE 4
This example describes a procedure for examining a test sample to
determine its glutamic-oxalacetic transaminase or glutamic-pyruvic
transaminase activity. For this example it is necessary to separate
the active enzyme fraction from the protein-free fraction of the
blood serum test sample. This separation may be accomplished within
the test pack shown in FIG. 1 by using a cartridge containing a gel
filtration material. Specifically, cartridge 18 of FIG. 1 is loaded
with 1.5 milliliter of hydrated polyacrylamide gel.sup.1. The test
sample is injected into the area 27 in stopper 19 and thence
through the gel in the cartridge as described on page 9.
Thereafter, a phosphate buffer is forced through the gel filtration
material containing the test sample in the same manner. The first
effluent containing the active enzyme is then channelled into the
reaction chamber of the test pack. After separation has been
accomplished, an additional amount of the phosphate buffer is
injected through channel 21 into the main reaction chamber of the
test pack.
In this analytical test pack, five compartments for reagents are
used. Compartment No. 1 is charged with 10.0 milligrams of
beta-nicotinamide adenine dinucleotide disodium salt (oxidized
form), 0.25 milligram of phenazine methosulfate, and 0.2 milligram
of 2,6-dichlorophenol indophenol. In compartment No. 2 there are 75
microliters of 1-glutamic dehydrogenase solution (100 micro-molar
units/milliliter). Cpmpartment No. 3 contains 1.35 milligram of
alpha keto-glutaric acid. Compartments Nos. 4 and 5 contain 30
milligrams of 1-aspartic acid and 25 milligrams of 1-alanine,
respectively. The reagent compartments are charged with
predetermined, but non-rate limiting, amounts of each compound.
Reagent compartments Nos. 1, 2, and 3 are ruptured and their
contents mixed with the main reaction chamber solution in the
manner disclosed in the previous examples. Depending on which
transaminase assay is desired, either compartment No. 4 or
compartment No. 5 is ruptured and its contents mixed with the main
reaction chamber solution.
The contents are mixed with the solution in the reaction chamber by
again applying a pulsating pressure and the result is "read out" in
a manner similar to that described in Ser. No. 502,596 by
determining absorbance or change in absorbance using light at 610
millimicrons to provide the concentration of the particular
dehydrogenase. Alternatively, the main reaction chamber and its
contents may be divided into two sections by the application of an
impulse sealer. One section may be heated to about 37.degree. C.
while the other section may be cooled to 5.degree. C. After a
suitable period, the two sections may then be read differentially
using a spectrophotometer. The concentration of the particular
enzyme in the test sample is determined from the differential
absorbance measurement.
* * * * *