Our new line of generic E. coli HCP kits utilize a new approach towards generic ELISA. Rather than offering a single assay, two assays are provided each employing a different anti-HCP antibody, and customers can then choose the assay which gives the best coverage for their process. This approach leads to the best detection of process-specific impurities, as no single antibody works well for all processes. This starter set is for quantitative measurment of host cell proteins in process related samples from E. coli BL21 cell lines. The BL21 starter set contains two complete ELISA kits with a range of 2-100 ng/mL and an assay time of 3h 35min.