Cadmium Purification and Quantification Using Immunochromatography

One of the pathways by which cadmium enters human beings is through the consumption of agricultural products. The monitoring of cadmium has a significant role in the management of cadmium intake. Cadmium purification and quantification using immunochromatography were conducted in this study as an alternative means of cadmium analysis. The samples used in this study were rice, tomato, lettuce, garden pea, Arabidopsis thaliana (a widely used model organism for studying plants), soil, and fertilizer. The cadmium immunochromatography has been produced from the monoclonal antibody Nx2C3, which recognize the chelate form of cadmium, Cd·EDTA. The immunochromatography can be used for quantification of cadmium in a range from 0.01 to 0.1 mg/L at 20% mean coefficient of variance. A chelate column employing quaternary ammonium salts was used for the purification of cadmium from HCl extracts of samples. Recoveries of cadmium were near 100%, and the lowest recovery was 76.6% from rice leaves. The estimated cadmium concentrations from the immunochromatography procedure were evaluated by comparison with the results of instrumental analysis (ICP-AES or ICP-MS). By comparison of HCl extracts analyzed by ICP-MS and column eluates analyzed by immunochromatography of the samples, the estimated cadmium concentrations were closely similar, and their recoveries were from 98 to 116%.