Electrochemical immunosensor based on hybrid MoS2/Pt@Au-nanoprism/PDA for simultaneous detection of free and total prostate specific antigen in serum

As important biomarkers for prostate cancer, total prostate specific antigen (tPSA) and free prostate specific antigen (fPSA) levels in serum play essential roles in early diagnosis. In this study, hybrid molybdenum disulfide (MoS 2 )/Pt@Au-nanoprism/polydopamine (PDA)-modified screen-printed electrodes were utilized to detect both fPSA and tPSA in serum simultaneously. MoS 2 generated by the hydrothermal method assembled on the electrode to provide binding sites for further modification. Au nanoprisms were obtained by reducing chloroauric acid with sodium thiosulfate to achieve uniformity. Pt nanoparticles covered on Au nanoprisms by the displacement method, and the generated Pt@Au-nanoprism structure was then deposited onto the electrode to enhance the electrochemical signals. An electropolymerization-synthesized PDA film further modified the electrode to increase antibody binding sites. The results demonstrated that the proposed electrochemical immunosensor for fPSA and tPSA analysis in serum using differential pulse voltammetry (DPV) had a wide linear range from 0.0001 ng/mL to 100 ng/mL, with limits of detection (3 SD/slope) at 0.1 pg/mL and 1.1 fg/mL, respectively. For clinical patient samples, the proposed biosensor demonstrated good accuracy according to the clinical electrochemiluminescence immunoassay and improved the diagnostic specificity of tPSA concentrations in the “gray zone", suggesting promising prospects for clinical applications of our multiplex biosensors.