Does interaction of monoclonal antibody charge variants with VEGF-A and ELISA reagents affect its quantification?

The ability of an enzyme linked immunosorbent assay (ELISA) to measure the concentration of charge variants of a monoclonal antibody (mAb) biotherapeutic has been investigated. Percentage recovery was found to be in the range of 80%–120% with inter and intra assay variation between 5% and 15%. Linear regression analysis of ELISA output at different dilutions yielded a good fit (R2 > 0.98). Assay output was not hindered by the presence of serum...