US 11,913,942 B2
Homogenous immunoassay with compensation for background signal
Murthy V S N Yerramilli, Falmouth, ME (US); Hongzhi Xie, Falmouth, ME (US); Daniel Wayne Patch, Portland, ME (US); and Giosi Farace, Georgetown, ME (US)
Assigned to IDEXX Laboratories, Inc., Westbrook, ME (US)
Filed by IDEXX LABORATORIES, INC., Westbrook, ME (US)
Filed on Jul. 8, 2020, as Appl. No. 16/924,081.
Application 16/924,081 is a continuation of application No. 15/048,209, filed on Feb. 19, 2016, granted, now 10,775,365, issued on Sep. 15, 2020.
Claims priority of provisional application 62/118,832, filed on Feb. 20, 2015.
Prior Publication US 2021/0018496 A1, Jan. 21, 2021
Int. Cl. G01N 33/53 (2006.01); G01N 33/542 (2006.01); G01N 33/68 (2006.01); C12N 9/04 (2006.01)
CPC G01N 33/5308 (2013.01) [C12N 9/0006 (2013.01); G01N 33/542 (2013.01); G01N 33/6812 (2013.01); C12Y 101/01049 (2013.01); G01N 2800/347 (2013.01)] 17 Claims
 
1. A method for conducting an assay for an analyte in a sample, comprising:
(a) conducting a sample first reaction sequence comprising:
i. forming a sample first reaction mixture by contacting the sample with an anti-analyte antibody, a conjugate comprising the analyte and an enzyme, and a substrate that produces a signal when in contact with the enzyme, and
ii. measuring signal from the sample first reaction mixture;
(b) conducting a sample second reaction sequence comprising,
i. forming a sample second reaction mixture by contacting the sample with the substrate and an anti-analyte antibody,
ii. measuring signal from the sample second reaction mixture;
(c) subtracting an amount of signal from step (b) from an amount of signal from step (a) to provide a net signal,
(d) using the net signal to determine the amount of the analyte in the sample.