Method and test strip for detection of residues

摘要

A method, test strip and method of manufacturing a test strip useful for detecting one or more analytes, such as an antibiotic, in a test sample such as a milk sample. The test strip and method include a labeled specific binder and test capture agent for the specific binder that increases test sensitivity to the analyte for which the specific binder has affinity while decreasing test sensitivity to an analyte for which a multianalyte binder has affinity.

主权项

1. A method for detecting at least two analytes, when present, in a test sample, said method comprising:
a) combining the sample with both a labeled specific binder and a labeled multianalyte binder to form an admixture, the specific binder having affinity to at least a first analyte but fewer than all the analytes to which the multianalyte binder has affinity and the multianalyte binder having affinity for (i) the at least one first analyte to which the specific binder has affinity and (ii) at least one second analyte to which the specific binder has less affinity than does the multianalyte binder; b) contacting the admixture with a test strip, the test strip configured to allow lateral flow of the admixture from a first end of the test strip to a second end of the test strip, the test strip having a test zone capable of capturing both the specific binder and the multianalyte binder, the test zone comprising at least two test zone capture agents, a first test zone capture agent having affinity for the specific binder when the specific binder is unbound by an analyte from the sample and a second test zone capture agent having affinity for the multianalyte binder when the multianalyte binder is unbound by an analyte from the sample; c) allowing the admixture to flow from the first end to the second end to contact the at least two test zone capture agents, wherein when any of the binders are captured at the test zone a detectable signal occurs in the test zone, the strength of which signal is relative to the combined amount of multianalyte binder and specific binder captured in the test zone, and wherein the combined amount of the multianalyte and specific binders captured in the test zone is inversely related to the total amount of analyte in the sample and wherein the presence on the test strip of both the specific binder and the first test zone capture agent (i) reduces the test sensitivity to the second analyte to which the multianalyte binder has affinity and to which the specific binder does not have affinity (ii) and increases test sensitivity to the first analyte to which the specific binder has affinity.