Apparatus for receiving a test specimen and reagent

• US 4,818,493 A
• Filed: 04/27/1987
• Issued: 04/04/1989
• Est. Priority Date: 10/31/1985
• Status: Expired due to Term

• Current Assignee: Bio/Data Corp.
• Original Assignee: Bio/Data Corp.
• Inventors: Sokol, Michael, Coville, William E., Grossman, Hyman
• Primary Examiner(s): Marcus, Michael S.
• Application Number:
  US07/043,113
• Time in Patent Office: 708 Days
• Field of Search: 422/63-67, 422/72, 422/73, 422/102, 422/104, 422/58, 422/61, 422/100
• US Class Current: 422/534
• CPC Class Codes: G01N 2035/00049 for loading/unloading a carousel
• CPC Class Codes: G01N 2035/00099 Characterised by type of test elements
• CPC Class Codes: G01N 2035/00138 Slides
• CPC Class Codes: G01N 2035/00376 Conductive heating, e.g. heated plates
• CPC Class Codes: G01N 2035/00435 Refrigerated reagent storage
• CPC Class Codes: G01N 2035/1025 Fluid level sensing
• CPC Class Codes: G01N 35/00029 provided with flat sample substrates, e.g. slides G01N35/028 takes precedence
• CPC Class Codes: G01N 35/025 having a carousel or turntable for reaction cells or cuvettes

Abstract

An apparatus for automatically performing analytical testing of individual distant samples of biological fluids wherein a test sample is reacted with test reagents and tested for a change in optical characteristics. A memory stores a plurality of different test protocols. An operator-actuated keyboard is used to select one of the test protocols from the memory. Individual distinct samples of biological fluid to be tested are received in a sample cell. The cell is heated to a preselected temperature. The apparatus transports an individual sample cell to a first location adapted to filter unwanted nonfluid material from the fluid to be tested and to remove excess fluid to be tested from the sample cell to cause a precise accurate volume of fluid to remain in the sample cell for testing. After filtering and removal of excess fluid, the apparatus transports the individual sample cell from the first location to a second location for introducing a first reagent into the sample, and then transports the sample cell from the second location to a test location where a second reagent is introduced into the sample. An optical detector at the test location optically scans the sample in a vertical direction to detect a change in an optical characteristic of the sample. The apparatus provides an alphanumeric indication that a change in the optical characteristic in the sample has been detected. The invention includes a uniquely configured sample cell for receiving the samples of fluid to be tested and unique apparatus for delivering precise volumes of a liquid reagent. A liquid reservoir is pressurized with gas to a preselected pressure and is automatically regulated to maintain the pressure at a constant value. A valve in conjunction with a nozzle and a conduit adapted to impart a constant flow rate to reagent being delivered is opened for precise, predetermined time intervals so that a precise predetermined volume of liquid flows through the valve in the predetermined time interval.

Claims

1. Apparatus for receiving a sample of a fluid to be tested and a test reagent, comprising:

(a) slide means having at least one cavity in a top surface thereof for receiving and holding a quantity of fluid to be tested, and

(b) body means slideably engaged with said slide means, said slide meand being slidable between a first position relative to said body means and a second position relative to said body means, a bottom surface of said body means facing the top surface of said slide means,

(c) said body means having at least one opening therethrough from its top surface to its bottom surface, said opening being in alignment with said at least one cavity in said slide means when said slide means is in said first position whereby fluid to be tested is introduced into said cavity through said opening,

(d) said body means also having at least one downwardly opening chamber therein, a lower end of said chamber being in the same plane as the bottom surface of said body means and being substantially open and an upper end of said chamber being substantially closed except for an opening therethrough, said chamber having a downwardly projecting member extending from said upper end of said chamber into said chamber, said chamber being in alignment with said at least one cavity in said slide means when said slide means is in said second position to form a test cell comprising said chamber and said cavity, said member being of a length such that the lowermost end thereof is below the surface of the fluid to be tested and reagent is said test cell, said member being adapted to conduct light from a light source through the fluid and the reagent in said test cell for enabling automated inspection of the fluid and the reagent in said test cell,

(e) the top surface of said slide means being in sliding contact with the bottom surface of said body means to form means for removing excess fluid to be tested from said at least one cavity as said slide means moves relative to said body means from said first position to said second position to cause a precise, accurate volume of fluid to remain in said cavity.

2. Apparatus according to claim 1, wherein the slide means and body means are made from a material transparent to electromagnetic radiation from near-infrared to ultraviolet frequencies.

3. Apparatus according to claim 1, further comprising stop means for preventing overtravel of said slide means from said first position to said second position.

4. Apparatus according to claim 1, wherein the number of cavities in the slide means, the number of openings through said body means and the number of downwardly openings chambers in said body means is equal to two.

5. Apparatus according to claim 1, wherein said slide means includes means between said slide means and said body means for trapping air bubbles in said fluid to be tested as said fluid is introduced into said cavity.

6. Apparatus for receiving a sample of fluid to be tested and a test reagent, said fluid containing non-fluid components, and for filtering said non-fluid components from said fluid, comprising:

(a) slide means having at least one cavity in a top surface thereof for receiving and holding a quantity of filtered fluid to be tested,

(b) body means slideably engaged with said slide means, said slide means being slidable between a first position relative to said body means and a second position relative to said body means, a bottom surface of said body means facing the top surface of said slide means,

(c) said body means having a plurality of fluid flow channels in a top surface and at least one opening therethrough from said channels to the bottom surface of said body means, said opening communicating with said at leasst one cavity in said slide means when said slide means is in said first position to deliver filtered fluid to said cavity,

(d) fluid reservoir means located on the top surface of said body means above said fluid flow channels, said fluid reservoir means having two chambers, each chamber having a top and a bottom end and being substantially open at its top end and substantially closed at is bottom end except for an opening therethrough, said opening communicating with said fluid flow channels, and

(e) filter means located between said fluid flow channels and said openings in the bottom ends of said fluid reservoir chambers for filtering said non-fluid components from said fluid,

(f) said body means also having at least one downwardly opening chamber therein separate from said fluid reservoir, a lower end of said chamber being in the same plane as the bottom surface of said body means and being substantially open and an upper end of said chamber being substantially closed except for an opening therethrough, said chamber having a downwardly projecting member extending from said upper end of said chamber into said chamber, said chamber being in alignment with said at least one cavity in said slide means when said slide means is in said second position to form a test cell comprising said chamber and said cavity, said member being of a length such that the lowermost end thereof is below the surface of the fluid to be tested and reagent in said test cell,

(g) the top surface of said slide means being in sliding contact with the bottom surface of said body means to form means for removing excess fluid to be tested from said at least one cavity as said slide means moves relative to said body means from said first position to said second position to cause a precise accurate volume of fluid to remain in said cavity.

7. Apparatus according to claim 6, wherein the slide means, body means and reservoir means are made from a material transparent to electromagnetic radiation from near-infrared to ultraviolet frequencies.

8. Apparatus according to claim 6, further comprising stop means for preventing overtravel of said slide means from said first position to said second position.

9. Apparatus according to claim 6, wherein said filter means comprises a porous polycarbonate sheet.

10. Apparatus according to claim 6, wherein said number of cavities in the top surface of said slide means and the number of said downwardly opening chambers in said body means is equal to two.

11. Apparatus according to claim 6, wherein the fluid flow channels are arranged in parallel rows.

12. Apparatus according to claim 6, wherein said slide means includes means between said slide means and said body means for trapping air bubbles in said fluid to be tested as said fluid is delivered to said cavity.