A colloidal gold immunoassay strip assay for cadmium detection in oilfield chemicals.

Cadmium ions (Cd 2+ ) are some of the major pollutants in oilfield chemicals. To reduce the pollution of oilfield chemicals, it is necessary to detect and control the content of Cd 2+ . In this study, we synthesized a highly sensitive and specific monoclonal antibody against Cd 2+ with an IC 50 of 1.97 ng mL -1 and no cross-reactivity. Based on this antibody, a colloidal gold immunoassay strip detection assay with an IC 50 of 1 mg kg -1 and a detection range of 1.0-20 mg kg -1 in oilfield chemicals was developed. This assay could be completed in 20 min and can be used for Cd 2+ on-site testing in oilfield chemicals and improve supervision efficiency in oil exploration and development.