In particular, Pan et al. developed an electrochemical biosensor based on carboxylated poly-lactide nanoparticles (PLLA) bioconjugated with a dual-antibody vascular endothelial growth factor antibody (anti-VEGF) and a PSA antibody (anti-PSA) for early diagnosis of prostate cancer. The gene discussed is KLK3; the disease is prostate carcinoma.