前列腺特异性抗体电化学免疫传感器的研制

利用自组装的方法在金电极上制得巯基丁二胺铜(Ⅱ)/纳米金胶/前列腺特异性抗体(抗PSA)免疫修饰电极。用该修饰电极对PSA进行检测,发现其循环伏安图的氧化还原峰电流都随PSA浓度的增高而降低,峰电位没有变化。其最佳实验条件包括:pH5.2的0.1mol/L磷酸盐缓冲液作为底液,以及用示差脉冲方式进行定量测定。结果显示:该传感器的氧化峰电流减少值与PSA浓度在0.005-0.48μg/mL范围内成线性关系,检测下限为2ng/mL.在40 ng/mLPSA浓度下八次测量相对标准偏差为2.9%,该免疫传感器的稳定性和抗干扰性都较好。对血清中的PSA进行检测,获得满意的结果。

The preparation of PSA immunology electrochemical biosensor

A mercaptobutamine Cu(Ⅲ)(CuL)absorbing Au colloid and PSA modified dectrode for the voltammetric determina- tion of PSA in serum is reported.The modified electrode is simply prepared on one Au electrode self-assembled by CuL,then in Au colloid/PSA antigen buffer solution.Optimum experimental conditions for PSA determination include a 0.1mol/L PBS buffer solution of pH 5.2,and the use of differential-pulse voltammetry(DPV)mode for measurement.The peak currents of differential pulse voltammograms decrease with the addition of PSA into the buffer solution while the peak potentials remain the same.The decreasing value of peak current ip is linear with PSA concentration in the range of 0.005-0.48μg/mL.The detec- tion limit is 2 ng/mL.Andthe relative standard deviation for 40 ng/mLPSA is 2.9%(n=8).The stability of this electrode is satisfactory.No serious interference is found.This method has been applied to determine PSA in serum samples.