电化学免疫法测定鸡肉组织中青霉素

Determination of Residual Penicillin in Chicken Muscle by an Electrochemical Immunosensor

将玻碳电极（GCE）表面氧化处理后,用戊二醛（GA）作交联剂,将新亚甲蓝（NMB）及辣根过氧化酶（HRP）标记的青霉素多克隆抗体（Ab＊）修饰到电极表面,制成高灵敏电流型青霉素免疫传感器。通过循环伏安法考察了电极表面的电化学特性,并对鸡肉中青霉素的残留进行了定量的研究。结果表明,传感器对鸡肉中含有的青霉素检测的线性范围是5-45 ng/g,相关系数为0.974 7,最低检出限为1.90 ng/g。考察了蛋白沉淀剂的沉淀效果,发现运用饱和硫酸铵对鸡肉中蛋白和脂类的沉淀效果最好。样品回收率最高为74.5%。干扰性实验表明,交叉干扰和鸡肉中其它成分干扰均较小。修饰的电极稳定性较好,可用于实际肉样中青霉素含量的测定。

A novel amperometric penicillin immunosensor was prepared by co-immobilizing new methylene blue（ NMB ） and horseradish peroxidase （HRP）-labeled penicillin polyclonal antibody （Ab ＊ ） on a glassy carbon electrode（GCE） pretreated by electrochemical oxidation and tailored with glutaraldehyde （GA） as the cross-linker through covalent bonding. The quantitative determination of residual penicillin in chicken muscle was investigated through cyclic vohammetry. The experiment results showed that the dependence of current on the concentration of residual penicillin was linear in a range of 5 - 45 ng/g, and the correlation coefficient was 0. 974 7, and the detection limit 1.90 ng/g. The test of the effect of precipitation showed that saturated ammonium sulfate was the best one among the three precipitators. Sample recovery rate was up to 74. 5 %. At the same time, interference experiment showed that the chicken cross-interference and interference from other components were small. Modified electrode had a good stability and can be used for the determination of penicillin in actual chicken samples.