Precise detection of prostate specific antigen in serum: A surface molecular imprinted sensor based on novel cooperated signal amplification strategy

Abstract

Prostate specific antigen (PSA) is of great significance for clinical detection. Herein, a surface molecular imprinted sensor based on a novel cooperated signal amplification strategy was constructed for the precise detection of PSA. MoS2 and gold nanoparticles were modified on the electrode surface as the sensing substrate, PSA template and 4-mercaptophenylboronic acid were employed to form the surface imprinted cavities, and the gold polymerized methylene blue composites labeled 4-mercaptophenylboronic acid was constructed as the tracing tag. Cyclic voltammetry, electrochemical impedance spectroscopy and differential pulse voltammetry measurements were performed to investigate the formation process of the sensor. Transmission electron microscopy, scanning electron microscopy and energy dispersive spectrometer analysis were utilized for the characterization of the sensing substrate and tracing tag. Once the target PSA was anchored on the sensor, an amplified signal was obtained by the cooperated electrochemical catalytic interaction of the nanomaterials on the tracing tag and substrate. The constructed sensor showed a wide linear range from 1.0 × 10−4 to 1.0 × 104 ng·mL-1, and the detection limit was 0.03 pg·mL-1. Besides, such a sensor exhibited favorable selectivity, reproducibility and stability in the assays, indicating an expected application prospect in the determination of tumor markers.