Nanoplasmonic biosensor: coupling electrochemistry to localized surface plasmon resonance spectroscopy on nanocup arrays.

The nanoscale Lycurgus cup arrays were hybrid structures of nanocups and nanoparticles with ultrasensitivity to refractive index change. In this study, an electrochemical localized surface plasmon resonance (LSPR) sensor was developed by coupling electrochemistry to LSPR spectroscopy measurement on the nanoscale cup arrays (nanoCA). Based on the combination of electrochemistry and LSPR measurement, the electrochemical LSPR on nanoCA was observed with significant resonance wavelength shifts in electrochemical modulation. The synchronous implementation of cyclic voltammetry and optical transmission spectrum can be used to obtain multiply sensing information and investigate the enhancement for LSPR from electrochemical scanning. The electrochemical enhanced LSPR was utilized as biosensor to detect biomolecules. The electrochemical LSPR biosensor with synchronous electrochemical and optical implement showed higher sensitivity than that of conventional optical LSPR measurement. Detecting with multi-transducer parameters and high sensitivity, the electrochemical LSPR provided a promising approach for chemical and biological detection.