U.S. patent number 3,776,699 [Application Number 05/190,813] was granted by the patent office on 1973-12-04 for red cell rinser.
This patent grant is currently assigned to The Cooke Engineering Company. Invention is credited to Ronald E. Gross.
United States Patent |
3,776,699 |
Gross |
December 4, 1973 |
RED CELL RINSER
Abstract
A red cell rinsing apparatus for preparing serological and like
test specimens of sera including a liquid manifold having a
plurality of ejection pipettes through which a plurality of
microquantities of rinsing liquid are simultaneously ejected, and a
carrier tray for supporting a plurality of red blood cell specimens
arranged in rows. The tray is manually moved and located underneath
the manifold successively to a plurality of predetermined portions
in which the respective rows of specimens are automatically aligned
with the ejection pipettes.
Inventors: |
Gross; Ronald E. (Springfield,
VA) |
Assignee: |
The Cooke Engineering Company
(Alexandria, VA)
|
Family
ID: |
22702902 |
Appl.
No.: |
05/190,813 |
Filed: |
October 20, 1971 |
Current U.S.
Class: |
422/50; 141/244;
141/266; 141/283; 422/65; 422/921 |
Current CPC
Class: |
B01L
3/0206 (20130101); G01N 21/11 (20130101); B01L
99/00 (20130101) |
Current International
Class: |
B01L
11/00 (20060101); B01L 3/02 (20060101); G01N
21/11 (20060101); A61m 001/03 (); B01l 011/00 ();
G01n 033/16 () |
Field of
Search: |
;23/258.5,253R
;141/244,266 ;73/423A,425.6 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Richman; Barry S.
Claims
What is claimed and desired to be secured by Letters Patent is:
1. Apparatus for preparing serological and like test specimens
comprising a support base, carrier means movably mounted on said
base, said carrier means being adapted to support a plurality of
specimen receptacles arranged in a plurality of side-by-side rows,
a fluid dispensing assembly mounted on said base and including a
fluid dispensing manifold fixed above said carrier means and a
plurality of dispensing elements connected to said manifold in
transverse alignment for simultaneously dispensing a quantity of
fluid into each of said plurality of transversely aligned specimen
receptacles, and advance means connected to said carrier means for
advancing said carrier means relative to said base beneath said
manifold sequentially through a plurality of predetermined
positions in which the specimen receptacles of adjacent rows are
successively operatively aligned with said dispensing elements.
2. The apparatus as defined in claim 1, said advance means
comprising manually operated actuator drive means connected to said
carrier means to advance said carrier means from one position to
another, and locator means associated with said carrier means to
automatically locate said carrier means in a selected one of said
predetermined positions.
3. Apparatus as defined in claim 1, said fluid dispensing assembly
comprising a mounting bracket for supporting said manifold from
said base, said mounting bracket being adjustably connected to said
base so that said manifold may be preferably adjusted relative to
said locator means to ensure that said dispensing elements are
preferably aligned with each row of specimens as said carrier means
is moved to each of said predetermined positions.
4. Apparatus as defined in claim 3, said mounting bracket including
a vertical leg to which said manifold is connected and a horizontal
leg having at least one opening through which the shank of a
fastening means extends to connect said horizontal leg to said
base, said opening being oversized with respect to said shank to
permit adjustment of said bracket and said manifold on said
base.
5. Apparatus as defined in claim 4, said dispensing assembly
comprising a locating bracket fixed to said manifold and adjustably
connected to said vertical leg of said mounting bracket to adjust
the height of said manifold above said carrier means.
6. Apparatus as defined in claim 3, said fluid dispensing assembly
comprising a fluid source, a manually actuated pipettor mounted on
said mounting bracket, conduit means connecting said pipettor to
said source and said manifold to fill said manifold, and said
manifold including a bleed valve assembly for venting air from said
manifold as said manifold is being filled.
7. Apparatus as defined in claim 6 wherein said manually actuated
pipettor is of the reciprocating plunger type adapted to withdraw
fluid from said source upon movement of said plunger in one
direction and to dispense fluid into said manifold upon movement of
said plunger in the other direction and is operative, when said
manifold is filled with fluid and said bleed valve is closed, to
eject measured quantities of fluid from said manifold through said
plurality of dispensing elements upon controlled movement of said
plunger by the operator.
8. Apparatus for preparing serological and like test specimens
comprising a support base; carrier means mounted on said support
base for movement between opposite ends of said base, said carrier
means being adapted to support a plurality of specimen receptacles
arranged in a plurality of side-by-side rows; a fluid dispensing
assembly mounted on said base and including a fluid dispensing
manifold fixed above said carrier means and a plurality of
dispensing elements connected to said manifold for dispensing a
quantity of fluid into each of said plurality of aligned specimen
receptacles; advance means comprising manually operated actuator
drive means to advance said carrier means relative to said base
through a plurality of predetermined positions in which the
specimen receptacles of adjacent rows are successively aligned with
said dispensing elements and locator means associated with said
carrier means to automatically locate said carrier means
sequentially in said predetermined positions, said actuator drive
means including a shaft extending between said opposite ends of
said base, spring means for biasing said shaft in one direction to
a home position and means for drive connecting said shaft to said
carrier means so that, when said shaft is manually moved in the
other direction, said carrier means is advanced therewith from one
preselected position to another preselected position, and said
locator means comprising stop means associated with said carrier
means and said base for positioning said carrier means in a next
predetermined position when said shaft is released to return to
said home position by said spring means.
9. Rinsing apparatus as defined in claim 8, said drive connecting
means comprising friction drive means coupling said shaft to said
carrier means.
10. Apparatus as defined in claim 9, said friction drive means
being formed by an L-shaped spring element one leg of which is
connected to said carrier means and the other leg of which
frictionally engages said shaft.
11. Apparatus as defined in claim 8, said stop means comprising a
stop member pivotally connected to said carrier means and a
plurality of longitudinally spaced locating abutments on said base
disposed for ratchetting cooperation with said abutments during
manual movement of said shaft and abutting cooperation to establish
said predetermined positions of said carrier means along said base
upon release of said shaft so that each row of specimen is
accurately aligned with said dispensing elements.
12. Apparatus as defined in claim 11, said stop member having one
end pivotally connected to said carrier means and a depending lug
spaced from said one end for engaging a respective lug of one of
said abutments to prevent return movement of said carrier means
with said actuating shaft when said shaft is released.
13. Apparatus as defined in claim 12, wherein said stop member
extends beyond said lug to provide a hand hold portion that may be
grasped to pivot said stop member in a direction to raise said lug
clear of said abutment and thereby permit return of said carrier
means toward said one end.
Description
BACKGROUND OF THE INVENTION
This invention relates generally to laboratory apparatus and, more
particularly, to a laboratory apparatus particularly useful in
simultaneously rinsing a plurality of red blood cells to prepare
serological and like test specimens of sera.
It is often necessary to rinse red blood cells to remove undesired
biological matter from the exterior of the cells so that the cells
are rendered suitable for test purposes.
In the past, red cell rinsing has been accomplished in closed
system washers or rinsers in which macroquantities of red cells
contained in bag-like containers are inundated and thoroughly mixed
by means of stirring mechanism in substantial volumes of washing
liquid or by manually positioning a single fluid ejection nozzle in
succession over the individual wells of a microtitration plate in
which each well contains a charge of red cells. The red cells,
after thorough stirring with the washing liquid and after the
stirrer is shut off, are allowed to settle out as a precipitate
leaving an upper stratum of waste washing liquid and preservative
and other removed matter which must be removed by draining it off
to the line of demarcation between the lower stratum of red blood
cells and the upper stratum of waste wash liquid. Typical examples
of such washers or rinsers are illustrated in U.S. Letters Pat. No.
3,351,432 issued Nov. 7, 1967 to K. Van Dyck et al. and U.S. Pat.
No. 3,399,040 issued Aug. 27, 1968 to J. C. Ilg. The rinsing
operation in both prior art practices is time consuming and uniform
rinsing is not assured.
SUMMARY OF THE INVENTION
Accordingly, the primary object of this invention resides in the
provision of a novel laboratory rinsing apparatus particularly
useful for simultaneously rinsing a plurality of red blood cell
samples distributed in microquantities in open wells of a plate
such as a microtitration plate.
Another object resides in the provision of a relatively simple,
inexpensive, manually operable laboratory rinsing apparatus in
which each row of wells of a microtitration plate is automatically
aligned underneath a plurality of wash fluid ejection pipettes so
that the wells may be simultaneously filled with a rinsing
solution.
Still another object resides in the provision of a novel laboratory
rinsing apparatus as in the previous object, wherein the apparatus
includes a manifold on which a plurality of pipettes are mounted
and a movable carrier for supporting a microtitration plate which
has a plurality of rows of red cell containing wells. The carrier
is movable underneath the manifold and is automatically located and
retained in a plurality of positions by an advance mechanism so
that each row of wells is properly aligned with the pipettes to
permit simultaneous dispensing of a rinsing solution in all of the
cells in each row.
Other objects and advantages of the invention will become apparent
from reading the following description of a preferred embodiment,
with reference to the drawings in which like numerals indicate like
elements.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a general perspective view of the red cell rinser of the
invention;
FIG. 2 is a top plan view of the rinser shown in FIG. 1;
FIG. 3 is a side elevation view of the rinser shown in FIG. 1;
FIG. 4 is a fragmentary front elevation view of the rinser taken
generally along line 4--4 of FIG. 3, with the syringe and rinsing
liquid reservoir removed;
FIG. 5 is a bottom plan view of the base member of the rinser taken
generally along line 5--5 of FIG. 3;
FIG. 6 is a fragmentary bottom plan view of the carrier tray on
which the microtitration plate is supported, illustrating the
manner in which the advancing and stop mechanism is connected to
the carrier;
FIG. 7 is a fragmentary sectional view of the advancing and stop
mechanism taken generally along line 7--7 of FIG. 6;
FIG. 8 is an enlarged perspective view of the manifold mounting
bracket;
FIG. 9 is a perspective view of the locator bracket which fastens
the fluid ejection manifold to the mounting bracket shown in FIG.
8; and
FIG. 10 is a fragmentary sectional view of the fluid ejection
manifold taken along line 10--10 of FIG. 2 and illustrating the
internal fluid passages of the manifold.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, the red cell rinsing apparatus 20
includes a chassis member 22 formed by a support base plate 24, and
side flanges 26 and 28, front flange 30, and rear flange 32 which
are bent upwardly from base plate 24. A number of suction cups 34
are fixed to the bottom of base 24 to hold the chassis in place on
a table or the like.
A pair of guide rails 36 and 38 are mounted on plate 24 along side
flanges 26 and 28, respectively, and a carrier tray 40 is slidably
supported along its outer edges 42 and 44 on rails 36 and 38, with
the tray having downwardly depending front and rear flanges 46 and
48. A locator plate 50 is mounted along each of the tray edges 42
and 44, and each of plates 50 has a pair of projecting pins 52
which function to accurately position a microtitration plate on
tray 40. The microtitration plate may be of any conventional type
having a plurality of wells, but it is preferably of the type shown
in U. S. Pat. No. 3,356,462 wherein there are eight rows of wells,
with twelve wells in each row, thus providing a total of 96 wells
in the plate.
Carrier tray 40 is sequentially advanced along rails 36 and 38 by
an advance mechanism including a shaft 54 which slidably extends
through flanges 30 and 32 of chassis 24 and flanges 46 and 48 of
tray 40, with a nylon grommet 56 being fixed to each of the flanges
and slidably receiving the shaft 54. A pushbutton knob 58 is fixed
on the front end of shaft 54 and a spring 60 acts between flanges
30 and knob 58 to bias shaft 54 toward the front end to a normal
"home" position. A pair of set screw collars 62 are fixed on shaft
54 to establish the forwardmost "home" position of shaft 54 and to
retain the shaft on chassis 22. Proper positioning of these set
screw collars 62, particularly the one adjacent knob 58, axially
along shaft 54 toward knob 58 is effected to establish the thrust
stroke of the advance mechanism from the normal "home" position to
a length slightly greater than the spacing between adjacent rows of
wells. This will assure proper stepped advancement of carrier tray
40 from one preselected rinsing position to a point slightly beyond
the ext position so the biasing spring 60 will be effective during
the initial portion of the return stroke of the advance mechanism
to firmly engage the stop mechanism, to be presently described,
when the next row of wells is aligned below the ejector tips
hereinafter described.
Shaft 54 is operatively connected to tray 40 to advance the tray
when knob 58 is pushed inwardly. As best shown in FIGS. 1, 3, 4, 7
and 8, the connection is provided by an L-shaped spring member 64
having a horizontal leg 65 fixed to the underside of tray 40 by
screws 66 which pass through the horizontal leg and thread into a
spring support block 68 to fasten the block and spring member 64
against tray 40. The shaft 54 passes through the spacing between
the vertical leg 70 of spring 64 and the opposing side of block 68,
with leg 70 frictionally engaging shaft 54 to cause tray 40 to move
rearwardly with the shaft when pushbutton 58 is depressed.
A stop lever or bar 72 is pivotally connected to the other side of
block 68 via screw 74. The bar extends upwardly through a slot 75
in tray flange 46 and includes an upturned knurled handle section
76 and a lower projecting tooth 78 (FIG. 3) which is adapted to
engage in a selected one of a plurality of detents or ridge
abutments 80 provided in the base 24 of chassis 22. The spacing
between ridges 80 corresponds to the spacing between the rows of
wells in the microtitration plate which will be positioned on tray
40. When knob 58 is depressed, shaft 54 is moved rearwardly to
advance tray 40 rearwardly (to the left in FIGS. 2 and 3) to the
next position because of the friction engagement with spring leg
70. As this occurs, tooth 78 rides along base 24 and, when knob 58
is released, shaft 54 is returned to its forwardmost position by
spring 60. However, tooth 78 will engage in one of the detents 80
to prevent return of tray 40 with shaft 54 which, as it returns,
will slide relative to spring leg 70.
A wash fluid ejection assembly 82 is mounted on chassis 22 above
tray 40 to simultaneously inject a predetermined 0.025 milliliter
micro volume of rinsing liquid into all of the wells of a single
row of wells in the microtitration plate. The assembly includes a
right angle bracket 84 (FIG. 8) having a lower horizontal leg 86
which has a pair of laterally spaced openings 88. Leg 86 is
connected to the bottom of base 24 via a pair of thumb screws 90,
the shanks of which extend through openings 88, and aligned
openings in base 24, and thread into tapped openings in a locator
plate 92 positioned on the top of base 24. The openings 88 in
bracket leg 86 are oversized with respect to the shanks of screws
90 so that bracket 86 is adjustable to permit proper lateral and
longitudinal alignment of assembly 82 relative to detents 80 which,
together with tooth 78, define the respective dispensing positions
of carrier tray 40.
The vertical leg 94 of bracket 84 extends upwardly adjacent chassis
flange 28 and supports at its uppermost end via block 96 an
automatic rinse liquid pipette 98, which may be any known
commercially available automatic pipetter such as a Cornwall
syringe -P5003-5. Syringe 98 is conventionally designed to draw
liquid from a supply container 100 via tubing 102 connected to
syringe 98 through a valve fitting 103 having an automatic one-way
valve mechanism for alternately opening and closing the inlet and
outlet branches in accord with the direction of movement of plunger
104. It delivers the rinse liquid via tubing 106 to a clear plastic
dispensing manifold 108 (FIG. 10) upon the downstroke of plunger
104. The manifold 108 is supported from bracket leg 94 via a
mounting bracket (FIG. 9) which has a vertical leg 112 provided
with an integral threaded pem nut 114, with leg 112 being fastened
to bracket leg 94 at a predetermined height above tray 40 by a
screw 116 which extends through the front one of slots 118 in leg
94. The transverse leg 120 of mounting bracket 110 also is provided
with a pair of integral threaded pem nuts 122, and a pair of screws
124 extend through openings 126 in manifold 108 and thread into
nuts 122 to fasten manifold 108 on bracket 110.
As shown in FIG. 10, manifold 108 includes a longitudinal
passageway 128 which is intersected by a plurality of equally
spaced vertical passageways 130. In the preferred embodiment
illustrated, there are twelve vertical passageways 130
corresponding to the 12 wells normally provided in each row of
wells in the conventional microtitration plates of the type shown
in U. S. Pat. No. 3,356,462.
A disposable plastic pipette tip 132, designed to deliver a 0.025
charge of rinse liquid, is mounted in each passageway 130 to eject
the liquid in twelve uniform micro streams that will successively
fill each of the 12 well rows of a microtitration plate upon
properly controlled step-by-step depression of plunger 104.
Manifold 108 also includes a small air bleed passage 134 which is
intersected by a slide valve 136 that extends through manifold 108
from front to back, with a nut 138 threaded on the back end of the
valve. The valve has a reduced center section 140, which when
aligned with vent 134 bleeds air from passageway 128 as plunger 104
is activated to initially fill the manifold with liquid. When the
manifold is filled, valve 136 is turned to block vent 134 and the
manifold is ready for ejecting the liquid into the wells of the
microtitration plate.
A typical red cell rinsing operation utilizing the present
invention will now be described.
Manifold 108 is filled by actuating the pipette plunger 104 several
times with valve 136 open to bleed any entrapped air from the
manifold via vent 134. When the manifold is filled, valve 136 is
closed readying rinser 20 for use. A microtitration plate, such as
that shown in Letters Patent No. 3,356,462, with a previously
deposited micro charge of red blood cells in each of its 96 wells,
is placed on carrier tray 40 which is then advanced into position
to bring the first row of twelve wells into position beneath the
row of 12 pipette tips 132, preferably constructed in accord with
the teachings of United States Letters Patent No. 3,276,639 issued
Oct. 4, 1966 to Jesse F. Lancaster. Plunger 104 is then pressed
downwardly in stepped sequence under operator control to
simultaneously eject, under positive pressure, a stream of
sufficient quantity of rinse liquid (about 0.025 milliliters from
each tip 132) into the red cell mass in each plate well to
forcefully disperse the rinse liquid into the red cell mass. The
plate is advanced by actuation of pushbutton or knob 58 to its next
position successively and repeated step-by-step until the red cells
in the wells of the eight rows have been dispersed with rinse
liquid.
The microtitration plate is then removed from carrier tray 40, a
conventional cover tape is placed over the top surface of the
microtitration plate to seal off each well from its neighboring
wells, and the dispersion of red cells and rinse liquid in the 96
wells is conventionally simultaneously centrifuged by placing the
taped plate in a centrifuge operating at about 1,000 RPM. This
centrifuging operation thoroughly intermixes the red cells and
rinse water in each well removing the cell contaminants and wetting
the cells themselves with the protective rinse water.
After centrifuging, the red cells settle out from the rinse liquid
into a precipitate in the form of a compacted mass of button shape
in the bottom of each well. The cover tape is then removed and the
excess rinse or waste liquid containing the undesirable
contaminants is removed preferably by tilting the plate to an angle
so that the microquantities of liquid in each cup can be poured
off. Since the red cell masses at this stage are in the form of a
silt-like wetted mass, they adhere to the bottom wall areas of the
plate wells in proper position for transferring the plate
containing the 96 rinsed red cell charges to further rinsing
operations and finally the desired test procedure to be performed
when the cells are sufficiently clean. Usually, three rinsings is
sufficient to provide suitable test specimens.
Proper alignment of the successive rows of wells beneath pipette
tips 132 is assured during the rinse liquid ejection procedure by
the engagement and nesting of ratchet tooth 78 in the next
successive detent 80 as the successive detents 80 are spaced a
distance equal to the spacing between the successive rows of wells
in the microtitration plate.
From the above description, it is apparent that the invention
provides a single, inexpensive rinsing apparatus which is easily
manipulated by a laboratory operation to quickly and accurately
supply optimum microquantities of liquid into a predetermined test
charge of red blood cell specimens deposited in a microtitration
plate for ultimate test procedures effecting a substantial time
saving and a saving of rinse solution and the test specimen
supplies by reason of the microquantities employed.
The invention may be embodied in other specific forms without
departing from the spirit or essential characteristics thereof. The
present embodiment is therefore to be considered in all respects as
illustrative and not restrictive, the scope of the invention being
indicated by the appended claims rather than by the foregoing
description, and all changes which come within the meaning and
range of equivalency of the claims are therefore intended to be
embraced therein.
* * * * *