Photoelectrochemical Immunosensor for Sensitive Quantification of Prostate Specific Antigen in Human Serum Samples Exploiting BaTiO3-CdS

摘要

A novel label-free photoelectrochemical immunosensor was developed for the determination of prostate-specific antigen (PSA) based on fluorine-doped tin oxide (FTO) electrode modified with barium titanate and cadmium sulfide (BaTiO3-CdS/FTO). The photoelectrochemical current density of the BaTiO(3)platform sensitized with CdS for the ascorbic acid (AA) donor molecule was higher than that observed in the absence of CdS. The BaTiO3-CdS/FTO platform was modified with PSA antibodies to produce the anti-PSA/BaTiO3-CdS/FTO immunosensor, which was incubated in solutions of PSA to inhibit the photocurrent density of the immunosensor for AA. The photocurrent density of the anti-PSA/BaTiO3-CdS/FTO immunosensor presented a linear relationship with the logarithm of the PSA concentration ranging from 1 pg mL(-1)to 1 mu g mL(-1)with good sensitivity. The proposed method presented an experimental detection limit of 1 pg mL(-1)(S/N=3). The immunosensor was successfully employed for the determination of PSA in blood serum samples, with recoveries between 98.7 %-104.4 %.