Polarization-Enhanced Janus MoSSe Plasmonic Biosensor for Accurate Diabetic Nephropathy Diagnosis

Accurate diagnosis of diabetic nephropathy (DN) is crucial for timely clinical intervention and increasingly relies on ultrasensitive detection of specific biomarkers. However, current detection methods are limited by low sensitivity and time-consuming procedures. Here, we present a Janus MoSSe-based plasmonic biosensor to significantly enhance charge sensitivity, enabling the ultrasensitive detection of DN biomarkers in urine. Through a heterogeneous engineering strategy, we synthesized Janus MoSSe monolayers with spontaneous out-of-plane polarization via chemical vapor deposition (CVD). This design amplifies charge sensitivity, leading to a significantly improved plasmonic biosensing performance, with an ultralow detection limit of 10^-15 g/L for key DN biomarkers. Furthermore, our biosenor successfully detects these biomarkers in clinical urine samples, outperforming conventional methods such as ELISA and enabling accurate, stage-specific DN diagnosis. This work not only broadens the application of Janus transition metal dichalcogenide monolayers but also offers a promising platform for the advanced clinical diagnosis of DN.