The use of E. coli for recombinant expression in the production of some proteins and plasmid DNA is a relatively simple and cost-effective way. The processes that use E. coli for product production are likely to contaminate host cell proteins (HCPs) from E. coli, and this contamination may reduce the efficacy of therapeutic drugs and lead to undesirable toxic or immune responses, so that the level of this contaminant needs to be minimized during purification of therapeutic drugs for use in humans or animals. ELISA is a simple to use, sensitive and objective test for HCPs.This kit uses the principle of double-antibody sandwich enzyme-linked immunosorbent assay (sandwich ELISA) to detect the residual E.coli HCP in samples. First, add the E.coli HCP standard and test sample to the Anti-E.coli HCP coated microtiter strips (36712-A), then add the diluted biotin labeled Anti-E.coli HCP antibody (36712-C), and finally add Streptavidin-HRP (36712-D) to form an antibody + antigen + antibody-Biotin + SA-HRP complex. Subsequently, add TMB substrate (36712-G) into the complex to observe color reaction after washing the complex. TMB was converted from colorless to blue and finally to yellow in the presence of termination solution (36712-H) catalyzed by HRPase. Shades of yellow were positively correlated with the amount of E. coli HCP detected in the sample. This kit can be used for the optimization of the purification process of biologics, the control of impurities in intermediate processes, and the release testing of final products. The detection range of this kit is 3.125~200 ng/mL; the lower detection limit is 2.22 ng/mL. Feature Highly sensitive: Detecting as little as 2.22 ng/mL of E.coli HCP residuals in in-process and final biological samples. Ensures accuracy: The E.coli HCP residuals can be accurately detected with a recovery of 75%-125%. Specificity: Specific detection of E.coli HCP without interference from other exogenous proteins. Stable: The difference between lot-to-lot is low, the kit property is not impacted under 37℃ for 7 days. Easy signal collection: Using Biotin-Streptavidin system, the signal can be stably enlarged. Application Residual E.coli HCP test in biological products Specification Sensitivity 2.22 ng/mL (range 3.125~200 ng/mL) Assay Time
