Specific-binding method for detecting substances, useful in sandwich immunoassays, based on binding of colloidal particle to a surface through nucleic acid hybridization

摘要

Specific-binding (M) for detecting a substance (A) in aqueous solution, is new. M comprises: (a) preparing a surface with specific-binding capacity for (A); (b) preparing a binding molecule (B), with specific-binding capacity for (A); (c) linking (B) to a colloidal particle (CP) to impart specific-binding properties; (d) combining surface, test sample and (B)-modified CP so that a surface-bound signal complex (SC) can form; and (e) detecting any CP present in SC. Independent claims are also included for: (1) article for performing M comprising CP with a nucleic acid (NA2) linked to it and one or more (B) containing a nucleic acid (NA1) complementary to NA2, where NA1/2 are linked; and (2) kit for preparing the article.