▎ 摘　　要

NOVELTY - Construction of potential selection ratio photoelectrochemical biosensor involves taking bismuth phosphate nanoparticles and bismuth phosphate nanoparticles with reduced graphene oxide, separately suspending in ultra-purified water, modifying two suspensions on indium tin oxide electrodes as working electrode, saturated mercury electrode as reference electrode and platinum wire as counter electrode, placing in electrochemical workstation, irradiating, electrochemically analyzing, changing external potential, finding external current close to zero potential and measuring critical potential. USE - Method for constructing potential selection ratio photoelectrochemical biosensor (claimed). ADVANTAGE - The method reduces intensity of external light source. DETAILED DESCRIPTION - Construction of potential selection ratio photoelectrochemical biosensor comprises taking bismuth phosphate nanoparticles and bismuth phosphate nanoparticles with reduced graphene oxide, separately suspending in ultra-purified water, modifying two suspensions on indium tin oxide electrodes as working electrode, saturated mercury electrode as reference electrode and platinum wire as counter electrode, placing three-electrode system in electrochemical workstation, irradiating by xenon lamp light source, electrochemically analyzing, changing external potential, finding external current close to zero potential, measuring critical potential, changing ionic strength of phosphate buffer solution, electrochemically detecting, adding ochratoxin A aptamer solution, putting into quartz cell containing phosphate buffer solution, and performing photovoltaic analysis.