Saliva assay method and device

• US 5,714,341 A
• Filed: 03/30/1994
• Issued: 02/03/1998
• Est. Priority Date: 03/30/1994
• Status: Expired due to Term

• Current Assignee: Orasure Technologies Incorporated
• Original Assignee: Epitope, Inc. (Orasure Technologies Incorporated)
• Inventors: Cimler, B. Melina, Klimkow, Nanette M., Thieme, Thomas R.
• Primary Examiner(s): Tsang, Cecilia J.
• Assistant Examiner(s): Mohamed, Abdel A.
• Application Number:
  US08/219,977
• Time in Patent Office: 1,406 Days
• Field of Search: 435/22, 435/4, 435/29, 435/805, 435/810, 436/63, 422/56, 422/58, 422/61, 422/102, 128/760, 128/762, 128/769, 128/771
• US Class Current: 435/22
• CPC Class Codes: A61B 10/0051 for taking saliva or sputum samples devices for receiving spittle A61J9/00
• CPC Class Codes: G01N 33/521 Single-layer analytical elements
• CPC Class Codes: G01N 33/5302 Apparatus specially adapted for immunological test procedures
• CPC Class Codes: G01N 33/558 using diffusion or migration of antigen or antibody immunochromatographic test strips G01N33/54387
• CPC Class Codes: Y10S 435/805 Test papers
• CPC Class Codes: Y10S 435/81 Packaged device or kit

Abstract

An improved method for determining the presence of an analyte in an oral fluid sample. A portion of the sample is mixed or contacted with a chromogenic substrate effective to produce a colored product upon reaction with α-amylase present in the sample. After a selected reaction time, the reaction mixture is inspected to determine the level of such colored product produced. Production of a level of colored product above a selected threshold within the reaction time indicates that an effective volume of undiluted oral fluid sample has been collected which is sufficient to allow detection of the analyte. A device for use in the method is also disclosed.

Claims

1. A method of determining the adequacy of amylase concentration quality in saliva from an oral fluid sample for the purpose of ensuring reliable detection of an analyte other than amylase, said method comprising the steps of:

i) collecting an oral fluid sample comprising amylase and suspected of containing the analyte;

ii) detecting the amylase concentration in said sample; and

,

iii) comparing said amylase concentration to a standard concentration to determine if the sample comprises adequate amylase concentration quality to reliably detect the analyte.

2. The method of claim 1 wherein the analyte is an immunoglobulin.

3. The method of claim 1 wherein the analyte is an immunoglobulin specific for a pathogen selected from the group consisting of HIV-1, HIV-2, hepatitis B, measles, mumps and rubella.

4. The method of claim 1, wherein the analyte is selected from the group consisting of cocaine, benzyolegonine, cotinine, amphetamine, and methamphetamine.

5. A method of claim 1 wherein the concentration of amylase is determined by the step of contacting the sample with a chromogenic amylase substrate effective to produce a colored product upon reaction with/amylase.

6. A method of claim 5 wherein the substrate yields chloro-nitrophenol upon, contact with amylase.

7. A method of claim 5 which further comprises the steps of collecting the oral sample onto an absorbent pad and submerging the absorbent pad into a vessel having a known volume of reaction medium containing a chromogenie amylase substrate effective to produce a colored product upon reaction with amylase present in the sample.

8. A system for minimizing false negative results in an analyte detection assay for oral fluids where said negative results arise from dilution of the analyte due to excessive amounts of saliva, said system comprising:

i) an apparatus having an absorbent means for collecting the oral sample comprising amylase and analyte by ensuring that the sample comprises an adequate amount of amylase;

ii) a reagent for detecting amylase by producing a colored reaction product in the presence of amylase said reagent positioned in the system to permit contact between the oral sample the reagent; and

,

iii) a colored standard for determining relative amylase concentration in a position permitting comparison between the colored reaction product of step ii and the colored standard said standard at a predetermined color intensity to minimize false negative results in the oral sample due to inadequate analyte concentration where said inadequate analyte concentration is due to dilution from saliva.

9. A system of claim 8 wherein the means for collecting the oral sample is an absorbent pad.

10. The system of claim 8 wherein the analyte is an immunoglobulin.

11. The system of claim 8 wherein the analyte is an immunoglobulin specific for a pathogen selected from the group consisting of HIV-1, HIV-2, hepatitis B, measles, mumps and rubella.

12. The system of claim 8, wherein the analyte is selected from the group consisting of cocaine, benzyolegonine, cotinine, amphetamine, and methamphetamine.

13. A system of claim 8 where the means for collecting the oral sample and the reagent are positioned so that they are in fluid contact when the oral sample is present.

14. A system of claim 13 where the apparatus further comprises a detection region in fluid contact with the reagent said detection region detecting the physical volume of the oral fluid sample.

15. A system of claim 14 wherein the detection region is physically separated from the reagent.

16. An apparatus for minimizing false negative results in assays for detecting analytes in oral samples where the apparatus comprises:

i) an absorbent means to collect an oral sample;

ii) a chromogenie reagent in fluid contact with the absorbent means wherein the chromogenic reagent produces a colored product upon reaction with amylase; and

,

iii) a fluid detection region in fluid contact with the chromogenic reagent wherein the detection region permits visual detection of total fluid present in the apparatus and wherein the fluid detection region comprises a reagent that chromogenically responds to water in a manner that is not dependent upon the presence or absence of amylase.

17. The apparatus of claim 16 wherein the means for collecting the oral sample is an absorbent pad.

18. The apparatus of claim 16 wherein the detection region is physically separated from the, reagent.

19. The apparatus of claim 16 wherein the analyte is an immunoglobulin.

20. The system of claim 16 wherein the analyte is an immunoglobulin specific for a pathogen selected from the group consisting of HIV-1, HIV-2, hepatitis B, measles, mumps and rubella.