CA1286578C - Test plate assembly defining discrete regions on a microporous membrane with low boundary distortion - Google Patents
Test plate assembly defining discrete regions on a microporous membrane with low boundary distortionInfo
- Publication number
- CA1286578C CA1286578C CA000509797A CA509797A CA1286578C CA 1286578 C CA1286578 C CA 1286578C CA 000509797 A CA000509797 A CA 000509797A CA 509797 A CA509797 A CA 509797A CA 1286578 C CA1286578 C CA 1286578C
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- plate
- apertures
- upper plate
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
- B01D61/14—Ultrafiltration; Microfiltration
- B01D61/18—Apparatus therefor
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- Life Sciences & Earth Sciences (AREA)
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- Health & Medical Sciences (AREA)
- Water Supply & Treatment (AREA)
- Food Science & Technology (AREA)
- Biochemistry (AREA)
- Hematology (AREA)
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- Urology & Nephrology (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Physics & Mathematics (AREA)
- Analytical Chemistry (AREA)
- Biomedical Technology (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analysing Biological Materials (AREA)
- Sampling And Sample Adjustment (AREA)
- Devices For Use In Laboratory Experiments (AREA)
Abstract
TEST PLATE ASSEMBLY DEFINING DISCRETE REGIONS ON
A MICROPOROUS MEMBRANE WITH LOW BOUNDARY DISTORTION
ABSTRACT OF THE DISCLOSURE
A biochemical test plate assembly for use in multiple simultaneous contact tests arranged in a fixed array of discrete regions on a single microporous mem-brane sheet provides less distortion of the boundaries of these regions than do pre-existing assemblies. Like its predecessors, the assembly contains two apertured plates; an apertured gasket sheet and a microporous membrane, both placed between the apertured plates; and a third plate for placement beneath the apertured plates, having a recess which serves as a reservoir for liquids passing through the membrane. The improvement resides in the enclosure of the lower apertured plate by the upper apertured plate and the base plate, thereby seal-ing the lower apertured plate and the microporous mem-brane off entirely from the atmosphere. This eliminates evaporation of moisture from the edges of the membrane, and any lateral diffusion of biochemical species which might occur as a result due to capillary attraction.
A MICROPOROUS MEMBRANE WITH LOW BOUNDARY DISTORTION
ABSTRACT OF THE DISCLOSURE
A biochemical test plate assembly for use in multiple simultaneous contact tests arranged in a fixed array of discrete regions on a single microporous mem-brane sheet provides less distortion of the boundaries of these regions than do pre-existing assemblies. Like its predecessors, the assembly contains two apertured plates; an apertured gasket sheet and a microporous membrane, both placed between the apertured plates; and a third plate for placement beneath the apertured plates, having a recess which serves as a reservoir for liquids passing through the membrane. The improvement resides in the enclosure of the lower apertured plate by the upper apertured plate and the base plate, thereby seal-ing the lower apertured plate and the microporous mem-brane off entirely from the atmosphere. This eliminates evaporation of moisture from the edges of the membrane, and any lateral diffusion of biochemical species which might occur as a result due to capillary attraction.
Description
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. 2558-185/BBBBBl TEST PLATE ASSEMBI,Y DEFINING DISCRETE REGIONS ON
A MICROPOROUS MEMBRANE WITH LOW BOUNDARY DISTORTION
This invention relates to an apparatus for bio-chemical testing and screening procedures involving the use of a microporous membrane.
A biochemical test plate assembly capable of handling multiple simultaneous tests involving a single microporous membrane is disclosed in Fernwood et al. r U.S. Patent No. 4,493,815, Bio-Rad Laboratories, Inc., January 15, 1985. The assembly provides a standard 8-by-12 rectangular array of cylindrical wells, with the bottom of each well sealed by a common microporous membrane. The membxane in turn rests above a recess forming an enclosed chamber from which a vacuum may be drawn or which may be completely sealed against air loss thereby providing a static air cushion beneath the membrane. The device may thus be used for either (a) drawing a fluid containing bïochemical species through the microporous membrane, or (b) supporting a static fluid above the membrane for an indefinite length of time. The exposed membrane regions collectively provide an array of discrete test regions with highly defined boundaries. Accurate automated detections can then be performed on the membrane after it is removed from the assembly.
The assembly generally consists of two aper-tured plates (an upper and a lowex) and a base platecontaining a recess to form the vacuum chamber beneath the welTs. The microporous membrane and an apertured gasket are placed between the two apertured plates.
The membrane is thus the only obstacle be-tween the upper plate apertures and the vacuum chamber, thereby permit ting both flow-thxough and static contact procedures, ' .. : ... . . .
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depending on the air pressure in the chamber. The wells and flow passages are sealed from the surr~unding room atmosphere by the apertured gasket between the two aper-tured plates, and a further gasket between the lowerapertured plate and base plate.
It is critical that these seals be perfectly air-tight so that prolonged tests can be done without loss of chamber pressure. This requires highly polished finishes at the surfaces where the seals are made, which adds considerably to the cost of manufacturing.
Furthermore, since the membrane must be fully moistened before assembly of the parts, the exposure of its outer edges to the atmosphere during the test proce-dures raises another disadvantage - evaporation from these edges. This induces outward migration of the biochemical species which have contacted the mer~rane through the ~utermost wells. ~he result is distortion of the outermost test regions on the membrane. This is a serious failing, since the lack of uniform contact areas obscures the test results in a number of ways.
An improvement over the device described above is offered by the present invention, in which the lower of the two apertured plates is fully enclosed by the remaining two plates. This reduces the number of seals which have atmospheric contact to a single seal ~etween the two enclosing plates. The microporous membrane is thus sealed off from the atmosphere entirely, and evap-oration from the membxane itself is eliminated as wellas any lateral diffusion driven by the resulting capil-lary attraction. With these features, the assembly of the present invention overcomes both of the problems mentioned above, while still retaining the same versa-tility of use and function. The result is a test plateassembly which provides even greater accuracy and repro-ducibility.
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The invention is illustrated, merely by way of example, in the drawings, in which:
FIG. 1 is an expanded view of one embodiment of a test plate assembly according to the present inven-tion;
FIG. 2A and FIG. 2B are a plan view and end view with cutawayl respectively, of the lower apertured plate shown as one of the components in FIG. l;
FIG. 3A and FIG. 3B are a plan view and a side sectional view, respectively, of the bottom plate shown in FIG. l; and FIG. 4, on the second sheet, is a side view in partial cutaway of the assembled parts of the embodiment shown in FIG. 1.
As in Fernwood et al., referenced above, the test plate assembly of the present invention is inten-ded to accommodate a multitude of simultaneous biochem-ical tests, each in one of a series of discrete wells or reservoirs arranged in a horizontal array. Although the number, size and spacing of the wells may vary, the most common and versatile arrangement is one comprising 96 circular wells in an 8-b~-12 rectangular array, with a center-to-center spacing of approximately 9mm, an arrangement used by a large variety of associated labo-ratory eguipment. Other examples include oval or slot-shaped wells with associated apertures of appropriate shape. For convenience, the drawings and the remainder of the description herein refer to a standard 96-well array.
FIG. 1 illustrates one embodiment of the test plate assembly of the invention. The assembly is desig-nated by the numeral 10, its primary parts consisting of an upper plate 11 having a plurality of apertures 12 arranged in the aforementioned array; a middle plate 13, also wi-th a plurality of apertures 14 aligned with those of the upper plate 11; a lower plate 15 containing ., ~
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a recess 16 sufficiently large to receive the middle plate 13; a gasket sheet 17, having apertures in the identical array and alignment of the upper and middle plates 11, 13; and a microporous membrane 19 of suffi-cient length and width to cover all of the apertures in the array.
The assembly is held together with foux cap-tive manually operated screws 20, with coil springs 21 for holding the screws in a raised position until they are pushed down and screwed into the lower plate 15.
This keeps the screw tips from interfering with the alignment of the porous membrane and gasket during as-sembly and disassembly. For convenience, the screws are captive in the upper plate 11, the threaded ends (not shown) mating with threaded holes 22 in the bottom plate 15 after passi~g through holes 23 in the gasket sheet 17.
Proper placement of the middle plate 13 inside the lower plate 15 is ensured by chamfering of the middle plate 13 at one corner 24 to mate with an angled corner segment 25 of the inner wall of the recess 16. Proper orienta-tion of the upper and lower plates is achieved by a pair of guideposts 26 along one side of the upper surface of the lower plate 15 to fit into corresponding holes (not shown) in the underside of the upper pla-te 11.
The middle plate 13 is shown in detail in FIGS. 2A and 2B~ Surrounding each aperture 14 is a boss 30 extending upward from the plate. The upper surface of each boss is flat and coplanar with each of the remaining bosses. The result is an even and concen-trated pressure on the gasket sheet 17 resting on top of the middle plate (see FIG. 1.) when the asse~bly is secured together, the pressure being concen-trated around the rims of the apertures.
The underside of the plate has an array of protruding ribs 31, which add structural strength to the plate and also keep the lower opening 32 of each aperture clear, avoiding stoppage of li~uid. As ~, . . ~ , .
- . ., : . ~ - :
' ' '' ~ ' . '~ ' ' ' '' ', 5~8 mentioned above, one corner 24 of the plate is cham-fered for purposes of proper orientation.
A detailed look at the lower plate 15 is of-fered in FIGS. 3A and 3B. It will be noted that therecess 16 is similar in lateral dimensions yet slightly larger than the middle plate 13, to snugly accommodate the latter. The angled wall 25 at one corner mates with the chamfered corner 24 of -the middle plate to ensure that the middle plate is inserted with the bosses facing upward.
The recess is surrounded by a ledge 40. When the parts of the assembly are secured together under the tension of the tightening screws, the ledge 40 is forced against the outer edge of the lower surface of the upper plate 11 through an intervening gasket, thus sealing the interior of the recess 16 from the labor-atory environment~ In the embodiment shown, the seal is achieved by a perimeter gasket (not shown) which rests in a machined groove 42 (shown in FIG. 3B) which completely encircles the recess 16. The gasket may assume any o a variety of conventional f~rms such as, for example, a large O-ring of circular cross-section (to mate with the curved groove 42 shown) or rectangular cross-section. Alternatively, the gasket may be combined with the gasket sheet 17 (see FIG. 1) as an extension thereof in the form of a protruding ridge. The latter is illustrated iIl FIG. 4, discussed in detail below.
Returning to FIG. 3B, the recess has a slant-ing floor 43 and a series of support posts 44 extendingupward ~rom the floor, on which the downwardly protrud-ing ribs 31 of the micldle plate 13 rest. This holds the middle plate above the sloping floor 43, defining an open space 45 below the middle plate to allow drain-3S age of any liquids passing through the apertures in themiddle plate. The sloping floor 43 promotes li~uid drainage toward a port ~6 at one side. The port may be connected to a vacuum line (not shown) for use of the ~' ' .
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assembly in performing a filter assay. Alternatively, the port may be closed by a valve (also not shown) to close off the inner space 45 of the base plate when a static blot assay is to be performed.
The assembled structure is shown in FIG. 4.
It will be noted that the peripheral seal is formed by a protruding ridge 47 on the gasket sheet 17, extending downward into the groove 42 which has been machined into the lower plate 15. The microporous membrane 19 lies entirely within the area defined by this protruding ridge 47. Accordingly, when the entire apparatus is assembled, and the apertures 12 in the upper plate are occupied by li~uid samples, the microporous membrane has no contact with the external atmosphere. Evapora-tion from the side edges and the resulting distortion of the test areas in the membrane is thereby avoided.
It is preferred that the range of compression of the peripheral seal exceed the range of compressio~
of the gasket sheet by the ~osses 30 around each set o~
aligned apertures. The peripheral seal will then be formed first as the securing screws are tightened, and less pressure is exerted on the individual aperture seals at the top of each boss. This minimizes distor-tion of the contact areas on the microporous membrane.This difference in the range of compression may be achieved in any of a variety of ways, but is most con-veniently achieved by selecting an appropriate height for the ridge 47 and thickness for the remainder of the gasket sheet 17.
Further features of the drawing show prefer-red embodiments o~ the structure. The apertures 12 in the upper plate, for instance, are generally cylindri-cal, the diameter of each undergoing a reduction from the upper surface of the plate to the lower surface.
This is useful in concentrating the biochemical species as it passes through the well and is deposited on the microporous membrane, improving the ease of detection .
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and subse~uent processing steps. To maximize the well capacity, the tapering portion is located toward the bottom of the aperture, providing a well capacity rang-ing from about 100 to about l,000 microliters in volume.
As another feature, the apertures 18 in thesheet gasket 17 are of slightly smaller diameter than bo-th those of the upper plate (at the narrower end) and the lower plate. In this way, the define~ test area on the microporous membrane 19 is slightly smaller than the diameter of the apertures in the plates, and slight misaligmnents of either the plates or the gasket sheet will not affect the size of the test area, since it will still be in full contact with the liquid either held in or passing through the wells.
The plates may be constructed of any rigid inert material, preferably transparent so tha-t the test fluids may be observed. Conventional materials will suffice, notably acrylic, polycarbonate, polypropylene or polysulfone. A convenient means of forming the plates is by injection molding. Since this avoids the need for machining of the plates individually, open spaces or gaps are easily incorporated into the structures to reduce the weight and the amount of plastic required.
The embodiments shown in the drawings are simplified, however, for a better understanding of the functional aspects of the construction.
As in the structure disclosed in Fernwood e-t al., referenced above, -the test p}.ate assembly of the present invention may be used for two basic modes of operation - ~orcibly drawing a fluid through the mem-brane, and retaining a ~luid above the membrane for a prolonged period of time. The former may be achieved by drawing a vacuum through the vacuum port g6, while the latter is achieved by sealing the port 46 from the atmosphere and retaining a slight positive pressure in the recess of the base plate below the middle plate.
These functions may be performed either individually or :' ' . '. ' ' ' ' ~ ., '': ' ., , - ' , . . : :
, ~ .' .
5~8 seguentially in a wide variety of biochemical laboratory procedures, with improved results in terms of accuracy, reproducibility, and lack of distortion.
The foregoing description is offered primari-ly for purposes of illustration. Although a variety of e~nbodiments has been disclosed, it is not intended that the present invention be limited to the particular struc~
tures or methods of operation set forth above. It will be readily apparent to those skilled in the art that numerous modifications and varia-tions not mentioned here can st.ill be made without parting from the spiri-t and scope of the invention as claimed hereinbelow.
- - .
~ - -: . .
~.
. 2558-185/BBBBBl TEST PLATE ASSEMBI,Y DEFINING DISCRETE REGIONS ON
A MICROPOROUS MEMBRANE WITH LOW BOUNDARY DISTORTION
This invention relates to an apparatus for bio-chemical testing and screening procedures involving the use of a microporous membrane.
A biochemical test plate assembly capable of handling multiple simultaneous tests involving a single microporous membrane is disclosed in Fernwood et al. r U.S. Patent No. 4,493,815, Bio-Rad Laboratories, Inc., January 15, 1985. The assembly provides a standard 8-by-12 rectangular array of cylindrical wells, with the bottom of each well sealed by a common microporous membrane. The membxane in turn rests above a recess forming an enclosed chamber from which a vacuum may be drawn or which may be completely sealed against air loss thereby providing a static air cushion beneath the membrane. The device may thus be used for either (a) drawing a fluid containing bïochemical species through the microporous membrane, or (b) supporting a static fluid above the membrane for an indefinite length of time. The exposed membrane regions collectively provide an array of discrete test regions with highly defined boundaries. Accurate automated detections can then be performed on the membrane after it is removed from the assembly.
The assembly generally consists of two aper-tured plates (an upper and a lowex) and a base platecontaining a recess to form the vacuum chamber beneath the welTs. The microporous membrane and an apertured gasket are placed between the two apertured plates.
The membrane is thus the only obstacle be-tween the upper plate apertures and the vacuum chamber, thereby permit ting both flow-thxough and static contact procedures, ' .. : ... . . .
, . . :. . . :
.
';' ' ' ' ' "
~L2~
depending on the air pressure in the chamber. The wells and flow passages are sealed from the surr~unding room atmosphere by the apertured gasket between the two aper-tured plates, and a further gasket between the lowerapertured plate and base plate.
It is critical that these seals be perfectly air-tight so that prolonged tests can be done without loss of chamber pressure. This requires highly polished finishes at the surfaces where the seals are made, which adds considerably to the cost of manufacturing.
Furthermore, since the membrane must be fully moistened before assembly of the parts, the exposure of its outer edges to the atmosphere during the test proce-dures raises another disadvantage - evaporation from these edges. This induces outward migration of the biochemical species which have contacted the mer~rane through the ~utermost wells. ~he result is distortion of the outermost test regions on the membrane. This is a serious failing, since the lack of uniform contact areas obscures the test results in a number of ways.
An improvement over the device described above is offered by the present invention, in which the lower of the two apertured plates is fully enclosed by the remaining two plates. This reduces the number of seals which have atmospheric contact to a single seal ~etween the two enclosing plates. The microporous membrane is thus sealed off from the atmosphere entirely, and evap-oration from the membxane itself is eliminated as wellas any lateral diffusion driven by the resulting capil-lary attraction. With these features, the assembly of the present invention overcomes both of the problems mentioned above, while still retaining the same versa-tility of use and function. The result is a test plateassembly which provides even greater accuracy and repro-ducibility.
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: ' . . .
-' .: ' : ''' . ' .. ': ' , : :
~2~3~57~
The invention is illustrated, merely by way of example, in the drawings, in which:
FIG. 1 is an expanded view of one embodiment of a test plate assembly according to the present inven-tion;
FIG. 2A and FIG. 2B are a plan view and end view with cutawayl respectively, of the lower apertured plate shown as one of the components in FIG. l;
FIG. 3A and FIG. 3B are a plan view and a side sectional view, respectively, of the bottom plate shown in FIG. l; and FIG. 4, on the second sheet, is a side view in partial cutaway of the assembled parts of the embodiment shown in FIG. 1.
As in Fernwood et al., referenced above, the test plate assembly of the present invention is inten-ded to accommodate a multitude of simultaneous biochem-ical tests, each in one of a series of discrete wells or reservoirs arranged in a horizontal array. Although the number, size and spacing of the wells may vary, the most common and versatile arrangement is one comprising 96 circular wells in an 8-b~-12 rectangular array, with a center-to-center spacing of approximately 9mm, an arrangement used by a large variety of associated labo-ratory eguipment. Other examples include oval or slot-shaped wells with associated apertures of appropriate shape. For convenience, the drawings and the remainder of the description herein refer to a standard 96-well array.
FIG. 1 illustrates one embodiment of the test plate assembly of the invention. The assembly is desig-nated by the numeral 10, its primary parts consisting of an upper plate 11 having a plurality of apertures 12 arranged in the aforementioned array; a middle plate 13, also wi-th a plurality of apertures 14 aligned with those of the upper plate 11; a lower plate 15 containing ., ~
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a recess 16 sufficiently large to receive the middle plate 13; a gasket sheet 17, having apertures in the identical array and alignment of the upper and middle plates 11, 13; and a microporous membrane 19 of suffi-cient length and width to cover all of the apertures in the array.
The assembly is held together with foux cap-tive manually operated screws 20, with coil springs 21 for holding the screws in a raised position until they are pushed down and screwed into the lower plate 15.
This keeps the screw tips from interfering with the alignment of the porous membrane and gasket during as-sembly and disassembly. For convenience, the screws are captive in the upper plate 11, the threaded ends (not shown) mating with threaded holes 22 in the bottom plate 15 after passi~g through holes 23 in the gasket sheet 17.
Proper placement of the middle plate 13 inside the lower plate 15 is ensured by chamfering of the middle plate 13 at one corner 24 to mate with an angled corner segment 25 of the inner wall of the recess 16. Proper orienta-tion of the upper and lower plates is achieved by a pair of guideposts 26 along one side of the upper surface of the lower plate 15 to fit into corresponding holes (not shown) in the underside of the upper pla-te 11.
The middle plate 13 is shown in detail in FIGS. 2A and 2B~ Surrounding each aperture 14 is a boss 30 extending upward from the plate. The upper surface of each boss is flat and coplanar with each of the remaining bosses. The result is an even and concen-trated pressure on the gasket sheet 17 resting on top of the middle plate (see FIG. 1.) when the asse~bly is secured together, the pressure being concen-trated around the rims of the apertures.
The underside of the plate has an array of protruding ribs 31, which add structural strength to the plate and also keep the lower opening 32 of each aperture clear, avoiding stoppage of li~uid. As ~, . . ~ , .
- . ., : . ~ - :
' ' '' ~ ' . '~ ' ' ' '' ', 5~8 mentioned above, one corner 24 of the plate is cham-fered for purposes of proper orientation.
A detailed look at the lower plate 15 is of-fered in FIGS. 3A and 3B. It will be noted that therecess 16 is similar in lateral dimensions yet slightly larger than the middle plate 13, to snugly accommodate the latter. The angled wall 25 at one corner mates with the chamfered corner 24 of -the middle plate to ensure that the middle plate is inserted with the bosses facing upward.
The recess is surrounded by a ledge 40. When the parts of the assembly are secured together under the tension of the tightening screws, the ledge 40 is forced against the outer edge of the lower surface of the upper plate 11 through an intervening gasket, thus sealing the interior of the recess 16 from the labor-atory environment~ In the embodiment shown, the seal is achieved by a perimeter gasket (not shown) which rests in a machined groove 42 (shown in FIG. 3B) which completely encircles the recess 16. The gasket may assume any o a variety of conventional f~rms such as, for example, a large O-ring of circular cross-section (to mate with the curved groove 42 shown) or rectangular cross-section. Alternatively, the gasket may be combined with the gasket sheet 17 (see FIG. 1) as an extension thereof in the form of a protruding ridge. The latter is illustrated iIl FIG. 4, discussed in detail below.
Returning to FIG. 3B, the recess has a slant-ing floor 43 and a series of support posts 44 extendingupward ~rom the floor, on which the downwardly protrud-ing ribs 31 of the micldle plate 13 rest. This holds the middle plate above the sloping floor 43, defining an open space 45 below the middle plate to allow drain-3S age of any liquids passing through the apertures in themiddle plate. The sloping floor 43 promotes li~uid drainage toward a port ~6 at one side. The port may be connected to a vacuum line (not shown) for use of the ~' ' .
-. . . . .
' . ' ' ' ,. ' '' ' ~' '. '.: ~ ' ,', :' ' ' - ' : ' ' ' ' ' '' " ;~ ' '. , . .' ' . .............. ' ' '. ' . ', . ..
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assembly in performing a filter assay. Alternatively, the port may be closed by a valve (also not shown) to close off the inner space 45 of the base plate when a static blot assay is to be performed.
The assembled structure is shown in FIG. 4.
It will be noted that the peripheral seal is formed by a protruding ridge 47 on the gasket sheet 17, extending downward into the groove 42 which has been machined into the lower plate 15. The microporous membrane 19 lies entirely within the area defined by this protruding ridge 47. Accordingly, when the entire apparatus is assembled, and the apertures 12 in the upper plate are occupied by li~uid samples, the microporous membrane has no contact with the external atmosphere. Evapora-tion from the side edges and the resulting distortion of the test areas in the membrane is thereby avoided.
It is preferred that the range of compression of the peripheral seal exceed the range of compressio~
of the gasket sheet by the ~osses 30 around each set o~
aligned apertures. The peripheral seal will then be formed first as the securing screws are tightened, and less pressure is exerted on the individual aperture seals at the top of each boss. This minimizes distor-tion of the contact areas on the microporous membrane.This difference in the range of compression may be achieved in any of a variety of ways, but is most con-veniently achieved by selecting an appropriate height for the ridge 47 and thickness for the remainder of the gasket sheet 17.
Further features of the drawing show prefer-red embodiments o~ the structure. The apertures 12 in the upper plate, for instance, are generally cylindri-cal, the diameter of each undergoing a reduction from the upper surface of the plate to the lower surface.
This is useful in concentrating the biochemical species as it passes through the well and is deposited on the microporous membrane, improving the ease of detection .
,. . ~ , .
. - . ~ . , . ., . ., : : . . ' , .
: - . - . ~ ~
.. . ..
... . , - . :
- : . . .
.
. . . : . .
~ 365~ ~
and subse~uent processing steps. To maximize the well capacity, the tapering portion is located toward the bottom of the aperture, providing a well capacity rang-ing from about 100 to about l,000 microliters in volume.
As another feature, the apertures 18 in thesheet gasket 17 are of slightly smaller diameter than bo-th those of the upper plate (at the narrower end) and the lower plate. In this way, the define~ test area on the microporous membrane 19 is slightly smaller than the diameter of the apertures in the plates, and slight misaligmnents of either the plates or the gasket sheet will not affect the size of the test area, since it will still be in full contact with the liquid either held in or passing through the wells.
The plates may be constructed of any rigid inert material, preferably transparent so tha-t the test fluids may be observed. Conventional materials will suffice, notably acrylic, polycarbonate, polypropylene or polysulfone. A convenient means of forming the plates is by injection molding. Since this avoids the need for machining of the plates individually, open spaces or gaps are easily incorporated into the structures to reduce the weight and the amount of plastic required.
The embodiments shown in the drawings are simplified, however, for a better understanding of the functional aspects of the construction.
As in the structure disclosed in Fernwood e-t al., referenced above, -the test p}.ate assembly of the present invention may be used for two basic modes of operation - ~orcibly drawing a fluid through the mem-brane, and retaining a ~luid above the membrane for a prolonged period of time. The former may be achieved by drawing a vacuum through the vacuum port g6, while the latter is achieved by sealing the port 46 from the atmosphere and retaining a slight positive pressure in the recess of the base plate below the middle plate.
These functions may be performed either individually or :' ' . '. ' ' ' ' ~ ., '': ' ., , - ' , . . : :
, ~ .' .
5~8 seguentially in a wide variety of biochemical laboratory procedures, with improved results in terms of accuracy, reproducibility, and lack of distortion.
The foregoing description is offered primari-ly for purposes of illustration. Although a variety of e~nbodiments has been disclosed, it is not intended that the present invention be limited to the particular struc~
tures or methods of operation set forth above. It will be readily apparent to those skilled in the art that numerous modifications and varia-tions not mentioned here can st.ill be made without parting from the spiri-t and scope of the invention as claimed hereinbelow.
- - .
~ - -: . .
~.
Claims (12)
1. A biochemical test plate assembly for use in both filter assays and static blot assays, said assembly comprising:
an upper plate having a plurality of aper-tures;
a middle plate having a plurality of aper-tures aligned with the apertures of said upper plate;
a lower plate having a recess which, when said lower plate is covered by said upper plate, defines an enclosed chamber of suffi-cient size to contain said middle plate;
means for forming an air-tight peripheral seal between said upper plate and said lower plate around said enclosed chamber;
a microporous film of sufficient size to span the apertures of said upper plate when placed between said upper plate and said mid-dle plate, yet lie within the area defined by said peripheral seal; and a gasket sheet having a plurality of aper-tures aligned with the apertures of said upper plate and adapted to form a lateral seal around the adjoining edges of each aligned pair of apertures when compressed between said upper plate and said middle plate.
an upper plate having a plurality of aper-tures;
a middle plate having a plurality of aper-tures aligned with the apertures of said upper plate;
a lower plate having a recess which, when said lower plate is covered by said upper plate, defines an enclosed chamber of suffi-cient size to contain said middle plate;
means for forming an air-tight peripheral seal between said upper plate and said lower plate around said enclosed chamber;
a microporous film of sufficient size to span the apertures of said upper plate when placed between said upper plate and said mid-dle plate, yet lie within the area defined by said peripheral seal; and a gasket sheet having a plurality of aper-tures aligned with the apertures of said upper plate and adapted to form a lateral seal around the adjoining edges of each aligned pair of apertures when compressed between said upper plate and said middle plate.
2. A biochemical test plate assembly accord-ing to claim 1 further comprising means for applying a vacuum to said enclosed chamber.
3. A biochemical test plate assembly accord-ing to claim 1 in which said recess includes a floor and means for supporting said middle plate above said floor, thereby defining a space between said middle plate and said floor to receive liquid passing through the apertures in said middle plate.
4. A biochemical test plate assembly accord-ing to claim 3 further comprising a vacuum port communi-cating said space with the exterior of said lower plate, and wherein said floor slopes toward said vacuum port.
5. A biochemical test plate assembly accord-ing to claim 3 in which said supporting means is com-prised of a plurality of posts extending up from said floor.
6. A biochemical test plate assembly accord-ing to claim 1 further comprising means for securing said upper plate, said microporous film, said gasket sheet, said middle plate and said lower plate together to compress said gasket sheet and said peripheral seal forming means sufficiently to form said lateral seals and said peripheral seals, respectively.
7. A biochemical test plate assembly accord-ing to claim 1 in which said peripheral seal forming means is comprised of a compressible gasket.
8. A biochemical test plate assembly accord-ing to claim 1 in which said peripheral seal is a com-pressible gasket, and the range of compression of said peripheral seal exceeds that of each said lateral sheet around the adjoining edges of said apertures.
9. A biochemical test plate assembly accord-ing to claim 1 in which all said apertures are of circular cross section, and each aperture in said gasket sheet is of smaller diameter than the apertures in both said upper plate and said middle plate with which said gasket sheet aperture is aligned.
10. A biochemical test plate assembly accord-ing to claim 1 in which each of the apertures in said middle plate terminates at its upper end in a flat boss extending upward from said middle plate, the uppermost surfaces of said bosses being coplanar.
11. A biochemical test plate assembly for use in both filter assays and static blot assays, said assembly comprising:
an upper plate having a plurality of cylindrical apertures of uniform size and spacing;
a middle plate having a plurality of cylindrical apertures of uniform size and spacing and aligned with the apertures of said upper plate;
a lower plate having a recess which, when said lower plate is covered by said upper plate, defines an enclosed chamber of suffi-cient size to contain said middle plate, said recess including a floor and means for support-ing said middle plate above said floor to de-fine a space below said middle plate for re-ceiving liquid, said floor being sloped toward one inner wall of said recess;
a port in said inner well of said recess for communicating said space with the exterior of said lower plate;
a microporous film of sufficient size to span the apertures of said upper plate when placed between said upper plate and said mid-dle plate yet lie within said recess;
a gasket sheet having a plurality of aper-tures aligned with the apertures of said upper plate and adapted to form a lateral seal around the adjoining edges of each aligned pair of
an upper plate having a plurality of cylindrical apertures of uniform size and spacing;
a middle plate having a plurality of cylindrical apertures of uniform size and spacing and aligned with the apertures of said upper plate;
a lower plate having a recess which, when said lower plate is covered by said upper plate, defines an enclosed chamber of suffi-cient size to contain said middle plate, said recess including a floor and means for support-ing said middle plate above said floor to de-fine a space below said middle plate for re-ceiving liquid, said floor being sloped toward one inner wall of said recess;
a port in said inner well of said recess for communicating said space with the exterior of said lower plate;
a microporous film of sufficient size to span the apertures of said upper plate when placed between said upper plate and said mid-dle plate yet lie within said recess;
a gasket sheet having a plurality of aper-tures aligned with the apertures of said upper plate and adapted to form a lateral seal around the adjoining edges of each aligned pair of
12 apertures when compressed between said upper plate and said middle plate;
and a perimeter gasket adapted to form a seal between said upper plate and said lower plate encircling said recess, the range of compression of said perimeter seal exceeding that of said gasket sheet.
and a perimeter gasket adapted to form a seal between said upper plate and said lower plate encircling said recess, the range of compression of said perimeter seal exceeding that of said gasket sheet.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US74317485A | 1985-06-10 | 1985-06-10 | |
| US743,174 | 1985-06-10 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1286578C true CA1286578C (en) | 1991-07-23 |
Family
ID=24987784
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000509797A Expired - Lifetime CA1286578C (en) | 1985-06-10 | 1986-05-23 | Test plate assembly defining discrete regions on a microporous membrane with low boundary distortion |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JPS6242056A (en) |
| CA (1) | CA1286578C (en) |
| DE (1) | DE3618884C2 (en) |
| GB (1) | GB2176601B (en) |
Families Citing this family (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1988006723A1 (en) * | 1987-02-24 | 1988-09-07 | Bionique Laboratories, Inc. | Disposable immunoassay and biochemical test device suitable for field and office use |
| FR2657543B1 (en) * | 1990-01-26 | 1992-12-18 | Biocom Sa | MODULAR DEVICE FOR COLLECTING, INCUBATING, FILTERING MULTIPLE SAMPLES. |
| JP2547354B2 (en) * | 1990-06-18 | 1996-10-23 | 迪郎 芝崎 | Method and apparatus for capturing sample having viscosity |
| US5141719A (en) * | 1990-07-18 | 1992-08-25 | Bio-Rad Laboratories, Inc. | Multi-sample filtration plate assembly |
| DE4107262A1 (en) * | 1991-03-07 | 1992-09-10 | Eppendorf Geraetebau Netheler | SUCTION DEVICE FOR MEMBRANE MICROTITER PLATES |
| JPH06506869A (en) * | 1991-04-04 | 1994-08-04 | ニコルソン プレシジョン インストルメンツ インコーポレイテッド | Vacuum clamp multiple sample filtration apparatus and method |
| DE4424112A1 (en) * | 1994-07-08 | 1996-01-11 | Raytest Isotopenmesgeraete Gmb | Process for the production of a sample carrier |
| US5881546A (en) * | 1994-09-16 | 1999-03-16 | Nippo Ltd | Spinning ring |
| DE19514521A1 (en) * | 1995-04-12 | 1996-10-17 | Schulz Hans Joachim Dr | Laboratory equipment for simultaneous manual performance of chemical reactions |
| FR2762092B1 (en) * | 1997-04-15 | 1999-05-28 | Bio Merieux | METHOD AND DEVICE FOR FILLING AN ANALYSIS CARD WITH A LIQUID MEDIUM |
| DE29709916U1 (en) * | 1997-06-06 | 1997-07-24 | Macherey Nagel Gmbh & Co Hg | Device for separating substances by means of negative pressure |
| US6893562B2 (en) | 2000-05-05 | 2005-05-17 | Millipore Corporation | Underdrain for filtration membrane |
| GB2410797B (en) * | 2001-07-31 | 2005-12-07 | Macaulay Land Use Res Inst | A connection device for use with multi-well plates |
| GB0118620D0 (en) * | 2001-07-31 | 2001-09-19 | Macaulay Land Use Res Inst The | Apparatus and method |
| AU2002340198A1 (en) | 2001-10-15 | 2003-04-28 | Biocept, Inc. | Microwell biochip |
| EP1491258B1 (en) * | 2003-06-24 | 2008-12-03 | Millipore Corporation | Multifunctional vacuum manifold |
| US6825478B1 (en) * | 2003-10-10 | 2004-11-30 | Perseptive Biosystems, Inc. | MALDI plate with removable magnetic insert |
| US6844545B1 (en) * | 2003-10-10 | 2005-01-18 | Perseptive Biosystems, Inc. | MALDI plate with removable insert |
| US8685749B2 (en) * | 2009-12-02 | 2014-04-01 | Whatman International Limited | Methods and systems for processing samples on porous substrates |
| US11385147B2 (en) | 2019-03-15 | 2022-07-12 | Seigniory Chemical Products Ltd. | System and method for filtering samples from vessels |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3378481A (en) * | 1966-01-03 | 1968-04-16 | Calvin A. Saravis | Biochemical test plate |
| DE2633283A1 (en) * | 1976-07-23 | 1978-01-26 | Dynatech Holdings Ltd | MICROTITRATION PLATE |
| US4427415A (en) * | 1979-01-05 | 1984-01-24 | Cleveland Patrick H | Manifold vacuum biochemical test method and device |
| US4526690A (en) * | 1983-02-04 | 1985-07-02 | Millipore Corporation | Apparatus for nucleic acid quantification |
| US4704255A (en) * | 1983-07-15 | 1987-11-03 | Pandex Laboratories, Inc. | Assay cartridge |
| US4493815A (en) * | 1983-07-28 | 1985-01-15 | Bio-Rad Laboratories, Inc. | Supporting and filtering biochemical test plate assembly |
-
1986
- 1986-05-12 GB GB08611533A patent/GB2176601B/en not_active Expired
- 1986-05-23 CA CA000509797A patent/CA1286578C/en not_active Expired - Lifetime
- 1986-06-04 JP JP13001286A patent/JPS6242056A/en active Granted
- 1986-06-05 DE DE19863618884 patent/DE3618884C2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| GB2176601A (en) | 1986-12-31 |
| DE3618884C2 (en) | 1995-04-06 |
| GB8611533D0 (en) | 1986-06-18 |
| JPH0585867B2 (en) | 1993-12-09 |
| JPS6242056A (en) | 1987-02-24 |
| GB2176601B (en) | 1989-02-01 |
| DE3618884A1 (en) | 1986-12-11 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |