Artificial metabolism-inspired photoelectrochemical probing of biomolecules and cells

Abstract

In this work, we have demonstrated the fabrication of Co₃O₄ nanoparticle-coated TiO₂ NWs with enzyme surface functionalization, which represent an artificial metabolism-inspired photoelectrochemical biomolecule probing design. Driven by the solar energy, the oxidative species formed on the Co₃O₄–TiO₂ photoanode serve as a charge shuttle between the photo-excited electrode surface and the redox enzyme that mimics a simple metabolism process, during which the enzyme can effectively function with high efficiency, thus leading to excellent sensitivity for metabolically important biomolecules. As a proof of concept, the successful probing of the ATP or cholesterol levels has been achieved using this Co₃O₄–TiO₂–enzyme platform, with the capability of measurement in serum samples or from cell extracts.