Electrophoresis-enhanced localized surface plasmon resonance sensing based on nanocup array for thrombin detection

Based on the special electrical and optical properties resulted from periodic nanostructure, localized surface plasmon resonance (LSPR) sensors have been widely used for various chemical and biological detections. Utilizing uniform alignment nanocups, an electrophoresis-enhanced LSPR sensor was designed for sensitive thrombin detection. The nanocup array was composed of nano-scaled funnel shaped cups with nanoparticles along the side walls. Through self-assembly, polyethylene glycol, thrombin-specific peptide, and bovine serum albumin were successively immobilized on the nanocup array. The results demonstrated that the synchronous implementation of electrophoresis and LSPR measurement could lead to obvious peak shifts in optical transmission spectra for detecting thrombin. The detection limit was as low as 10−11 M. With the high sensitivity and well linearity, the electrophoresis-enhanced LSPR sensing offered a novel design perspective for chemical and biological sensors with specific modifications on the nanosensor surfaces.