Solid-Phase Fluoroimmunoassay of Insulin Using Two Insulins Labeled with a Fluorescent Sulfobenzoxadiazolyl Group

Abstract

A solid-phase fluoroimmunoassay of insulin is described. The assay uses Gly(A1)- and Lys(B29)-[S-(4-sulfobenzoxadiazol-7-yl)-thioglycoloyl]-insulins which have a fluorescent sulfobenzoxadiazolyl group at a definite position, respectively. The immunoreactivities of these labeled insulins with a mouse anti-porcine insulin monoclonal antibody coated on polyacrylamide beads were compared using porcine insulin. The former labeled insulin provides 1.6-times greater immunoreactivity than does the latter and, thus, can afford a higher sensitivity in the assay.