An electrochemical biosensor to simultaneously detect VEGF and PSA for early prostate cancer diagnosis based on graphene oxide/ssDNA/PLLA nanoparticles

Early diagnosis of prostate cancer (PCa) is critical for the prevention of metastasis and for early treatment; therefore, a simple and accurate device must be developed for this purpose. In this study, we reported a novel fabrication method for producing a dual-modality biosensor that can simultaneously detect vascular endothelial growth factor (VEGF) and prostate-specific antigen (PSA) in human serum for early diagnosis of PCa. This biosensor was constructed by coating graphene oxide/ssDNA (GO-ssDNA) on an Au-electrode for VEGF detection, and incorporated with poly-_L-lactide nanoparticles (PLLA NPs) for signal amplification and PSA detection. The results showed that this biosensor has wide liner detection ranges (0.05–100 ng/mL for VEGF and 1–100 ng/mL for PSA), as well as high levels of sensitivity and selectivity (i.e., resisting interference from external factors, such as glucose, ascorbic acid human serum protein, immunoglobulin G, and immunoglobulin M), and demonstrated a high correlation with an enzyme-linked immunosorbent assay for sample detection in patients. Therefore, this biosensor could be utilized for early clinical diagnosis of PCa in the future.