The accurate, rapid and high-throughput measurement of IgG is essential in the development and manufacture of most therapeutic antibodies. Monoclonal antibodies are becoming increasingly dominant in biopharmaceuticals, where a vast number of samples must be screened for the development of each potential therapeutic.
Here we report the development of a novel, rapid, and simple fluorescence polarization based assay for high-throughput titer measurement of IgG and Fc-containing derivatives. It uses fluorescently labeled protein G that binds IgG. Upon binding, the depolarization of emitted light decreases, this can be detected to report on the presence of IgG. The CLARIOstar®, PHERAstar® and POLARstar® exhibit excellent assay quality when used with the ValitaTITER assay, which enables a high-throughput, simple, precise method for quantification of IgG. Moreover, the assay can be performed using sample straight cell culture supernatant, which means there are no complex sample preparation steps.