| abstract |
A reagent for a specific binding assay, such as an immunoassay, is prepared by reacting both a partner of a specific binding pair and at least one hydrophilic substance, with haloalkyl moieties associated with the surface of a solid phase, and then recovering the reagent so prepared for any unreacted binding partner. Preferably, the alpha-haloalkyl is chloromethyl and the at least one hydrophilic substance comprises at least one protein, such as aibumin, and at least one non-proteinaceous amine to which the solid phase is impermeable, such as tris (hydroxymethyl) aminomethane. The specific binding assay reagent of the invention can be combined with other reagents to provide an assay composition. |