Method for quantification of biological material in a sample

• US 5,700,655 A
• Filed: 02/23/1996
• Issued: 12/23/1997
• Est. Priority Date: 11/14/1995
• Status: Expired due to Term

• Current Assignee: BioControl Systems, Inc. (Merck & Co., Inc.)
• Original Assignee: IDEXX Laboratories Incorporated
• Inventors: Croteau, Andrew J., Naqui, Ali, Townsend, David E., Pierson, Mark W.
• Primary Examiner(s): Beisner, William H.
• Application Number:
  US08/606,229
• Time in Patent Office: 669 Days
• Field of Search: 435/30, 435/39, 435/40, 435/288.3, 435/288.4, 435/288.5, 435/288.7, 435/305.1, 435/305.2, 435/305.3, 435/305.4, 435/309.1, 435/810, 422/102, 73/864.02, 73/864.51, 73/864.72, 356/244, 356/246
• US Class Current: 435/30
• CPC Class Codes: B01L 3/5085 for multiple samples, e.g. microtitration plates
• CPC Class Codes: B01L 3/5088 confining liquids at a location by surface tension, e.g. virtual wells on plates, wires B01L3/50857 takes precedence
• CPC Class Codes: C12M 23/10 Petri dish crystallising dishes B01L3/06
• CPC Class Codes: C12M 23/12 Well or multiwell plates C12M25/04 takes precedence
• CPC Class Codes: C12M 23/20 Material Coatings immunocoatings C12M25/00
• CPC Class Codes: C12M 23/38 Caps; Covers; Plugs; Pouring means
• CPC Class Codes: C12M 37/00 Means for sterilizing, maintaining sterile conditions or avoiding chemical or biological contamination C12M23/38 takes precedence; filtration in general and filters per se B01D24/00-B01D41/00; autoclaves B01J3/04; treatment of microorganisms with electrical or wave energy C12N13/00
• CPC Class Codes: C12M 41/36 of biomass, e.g. colony counters or by turbidity measurements electrooptical investigation of individual particles G01N15/14, flow cytometers G01N15/1404

Abstract

Method for detection of a biological material in a sample. The method includes the steps of liquifying the sample (if necessary) and pouring the liquified sample into the incubation plate. The incubation plate has a generally flat horizontal surface and the surface is divided into a plurality of at least 20 recessed wells. Each well is adapted to hold an aliquot of liquid and is sized and shaped, and formed of a suitable material, to hold the aliquot within the well by surface tension. Any excess liquid from the liquified sample is poured from the surface of the plate. The method then involves incubating that incubation plate until the presence or absence of the biological material is determined.

Claims

1. A method for detection of the amount of a biological material in a sample, comprising the steps of:

liquefying said sample if necessary, and pouring the liquefied sample into an incubation plate comprising a generally flat horizontal surface, said surface defining a plurality of at least twenty recessed wells, each well being adapted to hold an aliquot of liquid and being sized and shaped, and formed of a material suitable to hold said aliquot within each said well by surface tension or by gelling of said liquid, said plate further comprising a landing pad area of size sufficient to hold the liquefied sample prior to dispersal of the sample to said wells;

pouring off any excess liquid from said incubation plate, and

incubating said incubation plate until the presence or absence of said biological material in one or more of said wells is determined so that the mount of said biological material can be determined.

2. The method of claim 1, wherein said method comprises applying said sample to said "landing pad" and subsequently providing a further liquid to simultaneously dilute said sample and disperse said sample into said wells.

3. The method of claim 1, wherein said incubation plate further comprises a pour spout to aid in removal of excess liquid not present in a well from said plate.

4. The method of claim 3, wherein said plate further comprises a lid having a slit adapted to cooperate with said pour spout to allow excess liquid to be poured from said incubation plate and to allow separation of said slit in said lid and said pour spout in said incubation plate to thereby permit incubation of the incubation plate without significant loss of liquid from said wells by evaporation.

5. The method of claim 1, wherein said surface defines at least 60 recessed wells.

6. The method of claim 1, wherein said plate is formed of plastic.

7. The method of claim 6, wherein said plastic is formed of a hydrophobic material.

8. The method of claim 1, wherein said plate is provided with a lid to prevent contamination of liquid in said wells.

9. The method of claim 1, wherein each said well is about 0.15 inch in diameter.

10. The method of claim 1, wherein each said well is chamfered to aid in the removal of excess liquid.

11. The method of claim 1, wherein said plate hah a lip to aid removal of excess liquid not present in a well from said plate.

12. A sterile incubation plate for determination of the mount of a biological material, comprising a generally flat horizontal surface, said surface defining a plurality of at least twenty recessed wells, each said well being adapted to hold an aliquot of liquid and being sized and shaped, and formed of a material suitable to hold said aliquot within each said well by surface tension and wherein said plate further comprises a landing pad adapted to hold a sample prior to aliquoting of said sample to said wells,

wherein said incubation plate will not provide any positive response for said biological material in the absence of a said biological material present in a sample applied to said plate.

13. The sterile incubation plate of claim 12, wherein said landing pad has a diameter of at least one inch.

16. The sterile incubation plate of claim 12, wherein said surface defines at least 60 recessed wells.

17. The sterile incubation plate of claim 12, wherein said plate is formed of plastic.

18. The sterile incubation plates of claim 17, wherein said plastic is formed of a hydrophobic material.

19. The sterile incubation plate of claim 12, wherein said plate is provided with a lid to prevent contamination of liquid in said wells.

20. The sterile incubation plate of claim 12, wherein each said well is about 0.15 inch in diameter.

21. The sterile incubation plate of claims 12, wherein each said well is chamfered to aid in the removal of excess liquid.

22. The sterile incubation plate of claim 12, wherein said plate has a lip to aid removal of excess liquid not present in a well from said plate.

14. The sterile incubation plate of 12, wherein said plate further comprises a pour spout.

15. The sterile incubation plate of claim 14, wherein said plate further comprises a lid having a slit adapted to cooperate with said pour spout to allow removal of liquid from said incubation plate.