The Research Of Immunoassay Method About Cr By Nanobody

In this study, p-SCN-Bn-DTPA was chosen as a bifunctional chelator to facilitate the synthesis of antigens for Cr, and the complete antigen Cr-DTPA-BSA/OVA with immunogenicity were gained successfully. The phage antibody against Cr-DTPA: Cr-DTPA-VHH 4-63 was produced through antibody library screening technology. The nanobody's relative affinity is 1.279×109 L/mol. There is no cross-reactivity between the antibody and the carrier protein or the non-metallic antigen, and other metals would not affect its detection.Based on the obtained nanobody, the indirect competitive ELISA immunoassay method for the detection of Cr was established initially. The limit of the detection for Cr was 6.6 ?g/L, IC50 was 75 mg/L and the spiked recovery results showed that the recovery were 90%-114%. It has reached the national drinking water standards and can be used to detect the heavy metal in agricultural irrigation water and drinking water. The topic combined the heavy metal immunoassay with antibody library screening technology successfully, providing a new idea of the further heavy metals detection and other immunoassay.