Electrochemical and piezoelectric quartz crystal detection of antisperm antibody based on protected Au nanoparticles with a mixed monolayer for eliminating nonspecific binding

The detection of antisperm antibody (AsAb) by electrochemical method based on Au nanoparticles with a mixed monolayer for eliminating nonspecific binding is presented. Impedance spectroscopy is used to characterize the modified procedures, the immobilization of sperm antigen (SpAg) and binding of AsAb in the presence of [Fe (CN)6]3−/4−. In addition, piezoelectric quartz crystal, PQC, was used to analyze the immobilization quantity of Au nanoparticles as well as to optimize experimental conditions. The change of electron-transfer resistance was correlated with the concentration of AsAb in a range from 25 to 600 mU/ml with the detection limit of 10 mU/ml. The analytical results of several human serum samples using the developed technique are in satisfactory agreement with those given by the enzyme-linked immunosorbent assay (ELISA) method.