Cd^(2+)人工抗原的制备及其抗体特性

Synthesis of Artificial Antigen and Characteristics of Polyclonal Antibody of Cadmium Ion

用异硫氰酸苄基乙二胺四乙酸(ITCBE)鳌合Cd2+合成Cd-ITCBE半抗原,异硫氰酯法制备免疫抗原Cd-ITCBE-BSA,紫外分光光度法(UV)、SDS-PAGE和电感耦合等离子体质谱法(ICP-MS)进行鉴定;用Cd-ITCBE-BSA免疫Balb/C小鼠,间接ELISA测定多抗血清(pAb)效价,阻断ELISA鉴定其敏感性,交叉反应试验鉴定其特异性。结果表明,Cd-ITCBE-BSA偶联成功,Cd-ITCBE-BSA中BSA和Cd2+的含量分别为7.1g/L和191.7 mg/L;间接ELISA效价达到1∶(5.12×104),阻断ELISA检测Cd-EDTA的IC50为26.9μg/L,除与Hg-EDTA具有较强交叉反应外,与EDTA及其他金属离子鳌和物无交叉反应,获得高效价、敏感、特异的Cd2+pAb,为Cd2+残留免疫学检测方法的建立奠定基础。

Artificial hapten Cd-ITCBE was synthesized using isotrhiocyanobenzyl-EDTA（ITCBE） to chelate cadmium ion（Cd2＋）.The method of isothiocyanate（ITC） was used to conjugate Cd-ITCBE to bovine serum albumin（BSA） and artificial immunogen Cd-ITCBE-BSA was obtained.Ultraviolet（UV）,sodium dodecyl sulfate polyacrylamide gel electropheresis（SDS-PAGE） and inductively coupled plasma mass spectrometry（ICP-MS） were used to identify Cd-ITCBE-BSA.Balb/C mice were immunized with Cd-ITCBE-BSA,the titres of polyclonal antibody（pAb） was detected by indirect ELISA,the sensitivity of pAb was identified by blocking ELISA and the specificity of pAb was identified by cross-reaction.The results showed that Cd-ITCBE-BSA was synthesized successfully and its concentration of BSA and Cd2＋ was 7.1 g/L and 191.7 mg/L,respectively.The Cd2＋ pAb had high titers of 1∶（5.12×104） by indirect ELISA,a good sensitivity with the 50% inhibition quality concentration（IC50） of 26.9 μg/L to Cd-EDTA by blocking ELISA,a high cross-reactivity to Hg-EDTA and little or no cross-reactivity to other compounds.The high-titer,sensitive and specific Cd2＋ pAb was produced in sera of immunized Balb/C mice,which made it possible to establish immunoassay of Cd2＋ residues in animal food.