Synthesis Of Artificial Cadmium Antigen And Preparation Of Anti-cadmium Monoclonal Antibodies

Heavy metals are toxic and persistent environmental contaminants. Unlike carbon-based contaminants that can be completely degraded to relatively harmless products, metal ions can be transformed in only a limited number of ways by biological or chemical remediation processes. While such transformations are intended to limit the toxicity or solubility of a given metal species, there are usually competing processes in nature that will eventually recycle at least some of the metal ions back into their original highly toxic state. Metals often persist in the environment for long periods of time bound to soils or sediments; such bound metals are relatively non-toxic except to bottom-feeding animals. Unfortunately, changes in weather, in the pH of the soil or water, or in other combinations of environmental factors can mobilize bound metals and greatly increase their availability and effective toxicity.Detection of cadmium still depends on traditional instruments. But immunoassays have the characteristics of quick, inexpensive, simple to perform, and reasonably portable, highly sensitive and selective and so on. So immunoassays have been focused home and abroad in recent years.In our study, cadmium ions was coupled to Keyhole Limpet Hemocyanin(KLH) via EDTA to gain the complete antigen(KLH-EDTA-Cd). After the protein concentration assay of the antigen with Bicinchoninic Acid (BCA) method, the complete antigen was scanned with ultraviolet spectrophotometer, and verified with SDS-PAGE. Concentration of cadmium ion in complete antigen was determined with Graphite-furnace Atomic Absorption Spectrometry (AAS). Several BALB/C mice were immunized with this immunoconjugate. Spleen cells of an immunized mouse was fused with myeloma cells and the hybridomas were screened by ELISA and cloned by the limiting dilution. Three hybridoma cells lines D11-2, F6-5å’ŒH9-8 that produced MAbs with high selectivity and sensitivity were obtained. The titers of the culture supernatant of three hybridoma (D11-2, F6-5å’ŒH9-8) were 1:200, 1:400, 1:800 and ascites titers reached 1:2000,1:4000, 1:8000, respectively. Anti-cadmium monoclonal antibodies were obtained and established a foundation for further study on technology of measuring cadmium in natural materials.