Method for detecting the presence of an analyte in a sample

A method for determining whether one or more members of an analyte family is present in a test sample at or above a predetermined threshold level, wherein the predetermined threshold level for one member of said analyte family differs from the predetermined threshold level for at least one other member of said analyte family, said method comprising the steps of:

• (a) allowing said sample to contact a receptor, wherein said receptor is characterized by an ability to bind to at least two members of said analyte family, so as to allow said receptor to bind said at least two members of said analyte family in said sample, if present, to form an analyte-receptor complex with said present member, whereby said method has an initial analyte-specific test sensitivity level for each of said at least two members respectively;
• (b) prior to, concurrently with, or subsequent to step (a), allowing said sample to contact an amount of one or more analyte-specific adjustment binders, each adjustment binder having binding specificity for at least one selected member of said analyte family but not all of said at least two members of the analyte family, said analyte-specific adjustment binder competing with said receptor for binding to said at least one selected member, the amount of each of said one or more analyte-specific adjustment binders chosen to make an amount of said at least one selected member unavailable for binding to said receptor, said amount of unavailable selected member being sufficient to adjust said selected member's respective sensitivity level to said selected member's predetermined threshold level;
• (c) subsequent to steps (a) and (b), allowing said sample to come into contact with a receptor binder on a solid support, said receptor binder characterized in that said receptor binder binds to the receptor but does not bind to the analyte-receptor complex;
• (d) prior to, concurrently with, or subsequent to steps (a)–(c), allowing said receptor to be tagged with a detectable label;
• and
• (e) detecting receptor bound to said receptor binder on said solid support as an inverse indication of the presence of one or more of said members of said analyte family in said sample at or above said predetermined threshold level.