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 (0.05-100ng/mL for VEGF and 1-100ng/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.

Label-Free Biochips for Accurate Detection of Prostate Cancer in the Clinic: Dual Biomarkers and Circulating Tumor Cells.

Purpose: Early diagnosis of prostate cancer (PCa) is essential for the prevention of metastasis and for early treatment; therefore, we aimed to develop a simple, accurate, and multi-analyte assay system for early PCa diagnosis in this study. Experimental design: We fabricated three kinds of biochips then integrated into microfluidic device for simultaneous detection of vascularendothelial growth factor (VEGF), prostate-specific antigen (PSA), and PCa circulating tumor cells (CTC) in human serum for accurate diagnosis of PCa. Then the integrated device can be put in the ELISA reader for signal analysis after sample incubation, no necessary of further fluorescence staining or microscopy counting. Result: The integrated device has wide liner detection ranges (0.05-25 ng/mL for both PSA and VEGF, and 5-300 cells/mL for PCa CTC), as well as high levels of sensitivity and selectivity, and demonstrated a high correlation with an enzyme-linked immunosorbent assay for sample detection in patients. Also, the presented biochips could maintain their stability when stored at 37°C for 49 days without significant differences in the red-shift (<5%). Conclusions: We have successfully developed a multi-analyte sensing system for rapid and easy detection of PSA, VEGF, and PC3 cells in PCa samples using label-free glass-based chips. This method presents the advantages of a broad working range, high specificity, label-free, high-speed, stability, and low cost detection method for point-of-care testing of PCa.