MXene/PEDOT:PSS-based dual-biomarker impedimetric immunosensor for accurate differentiation of prostate cancer from BPH through urinary detection

Abstract

Prostate cancer (PCa) is the second most common cancer among men worldwide. Although prostate-specific antigen (PSA) is widely used for PCa screening, it lacks specificity for distinguishing PCa from benign prostatic hyperplasia (BPH). β-2-microglobulin (β2m) is a sensitive biomarker for malignant tumors and can complement the PSA for improved diagnostic accuracy. In this study, a non-invasive dual-biomarker electrochemical immunosensor was developed for urinary detection of PSA and β2m. A gold electrode was modified with MXene deposition and PEDOT:PSS electropolymerized on MXene, then functionalized with PSA and β2m antibodies. The composite MXene/PEDOT:PSS (MX/PP) electrode enabled sensitive detection through electrochemical impedance spectroscopy (EIS), which achieved detection limits of 4.96 × 10？5 ng/mL for PSA and 1.1 × 10？4 ng/mL for β2m. A wide linear range (approximately 0.01？600 ng/mL) was demonstrated for both the biomarkers in urine. The sensor exhibited high selectivity, reproducibility, stability, and effective differentiation between PCa and BPH. The MX/PP interface provided enhanced conductivity and surface area for antibody functionalization. This simple dual immunosensor offers a promising platform for the non-invasive, accurate, and early diagnosis of prostate cancer.