A research team led by The Hong Kong University of Science and Technology (HKUST) has developed an optical plasmonic tweezer-controlled Surface-Enhanced Raman Spectroscopy (SERS) platform that utilizes on-and-off control of light to probe various amylin species in mixtures at the single-molecule level, unveiling the heterogeneous structures of pH-dependent amylin species, and the secrets behind amyloid aggregation mechanisms associated with type 2 diabetes.