the assay described herein is predicated on an observation that when acridinium ester labeled tracers are bound to their corresponding binding conjugate immobilized on a metal oxide solid phase , the measurable chemiluminescent light emission of the labeled tracer bound to the solid phase is quenched as compared to the free fraction tracer that is unattached to the solid phase . according to the invention , a non - separation specific binding assay to detect or quantify the presence of an analyte is provided where the entire reaction mixture is flashed and modulated signal is associated with a reference , thus determining the amount or presence of said analyte in said sample . disadvantages inherent in heterogeneous assays employing multiple separations may be avoided using this non - separation method .