This kit is designed to quantify the recombinant Protein A ligands used in the Avantor J.T.Baker® BAKERBOND® PROchievA™chromatographic resins. It features an assay protocol that eliminates sample boiling and the subsequent centrifugation step, thereby reducing assay time by more than 1 hour. This assay provides a simple to use, precise, and highly sensitive method to detect Avantor J.T.Baker® BAKERBOND® PROchievA™ Protein A impurity to less than 300 pg/mL in the presence of up to mg/mL quantities of humanized monoclonal antibodies. As such, this kit can be used as a tool to aid in optimal purification process development and in routine quality control of in-process streams as well as final product.