摘要
目的制备抗镉离子螯合物的多克隆抗体,初步建立检测镉离子的ELISA竞争法。方法用双功能螯合剂iEDTA螯合Cd2+后,再与匙血蓝蛋白(KLH)偶联,合成完全抗原(Cd-iEDTA-KLH),免疫BALB/c小鼠,获得多克隆抗体。ELISA法检测其抗血清效价、特异性和灵敏度。结果多克隆抗体效价均大于1∶80000;特异性检测结果显示均产生了抗Cd-iEDTA抗体,与OVA、BSA无交叉反应。抗体除与Hg2+有较强的交叉反应外,同等抑制情况下,Mg2+、Ca2+、Fe3+、Cu2+、Ni2+、Zn2+与Cd2+浓度相差约1000倍,交叉反应率很低;ELISA竞争法对镉离子的检测限约为50ng/ml。结论初步建立了镉离子的ELISA竞争法,检测限达到无公害的国家卫生限量标准(100ng/g)。
Objective To prepare the polyclonal antibody against cadmium ion chelate and develop a competitive ELISA for cadmium.Methods Chelate cadmium ion with bifunctional chelating agent isothiocyanobenzyl-EDTA （iEDTA） and couple to keyhole limpet hemocyanin （KLH）. Polyclonal antibody was prepared by immunizing BALB/c mice with the synthetic complete antigen Cd-iEDTA-KLH and analyzed for titer, sepcificity and sensitivity by ELISA. Results The prepared polyclonal antibody reached a titer of more than 1 ： 80 000 and showed no cross reaction with OVA, BSA or many other heavy metal ions. However, it showed strong cross reaction with mercury ion. The sensitivity of the prepared antibody for cadmium ion was 1 000 times higher than those for other heavy metal ions including nmgnesium, calcium, iron, copper, nickel and zinc ions. The detection limit of cadmium ion by competitive ELISA with the prepared polyclonal antibody was 50 ng/ml. Conclusion A competitive ELISA for cadmium ion with polyclonal antibody was preliminarily developed, and its detetion limit met the requirement for safety of non-environmental pollution aquatic products.
出处
《中国生物制品学杂志》
CAS
CSCD
2008年第1期56-59,共4页
Chinese Journal of Biologicals
基金
广东省科技计划项目基金资助(粤财企[2003]209
2003C20411)
