Abstract
Photoelectrochemical (PEC) biosensing with plasmonic nanoparticles is an attractive detection method due to the combined advantages of photo-excitation and electrochemical detection. In this paper we develop a new nanocomposite, TiO2@Ag@Ag3PO4, as a plasmon-based PEC sensing platform for monitoring Ca2+ release from living cardiomyocytes. This nanocomposite exploits the benefits of TiO2 nanowires for high stability, fast charge transport kinetics, facile surface functionalization, and environment benignity. In addition, the incorporation of a thin layer of silver@silver phosphate (Ag@Ag3PO4) core shell nanoparticles can enhance the photoabsorption and charge transport of TiO2. The resulting synergistic effects on the composite lead to an excellent PEC sensing performance of Ca2+ ions in both buffer solutions and from living cardiomyocytes. (C) 2015 Elsevier B.V. All rights reserved.