A sensitive and stable visible-light-driven photoelectrochemical aptasensor for determination of oxytetracycline in tomato samples

Key Words:SURFACE-PLASMON RESONANCE; GRAPHENE QUANTUM DOTS; ESCHERICHIA-COLI; CARRIER LIFETIME; PERFORMANCE; EFFICIENT; HETEROJUNCTION; PHOTOCATALYST; DEGRADATION; PHOTOACTIVITY

Abstract:Sensitive detection of oxytetracycline (OTC) has attracted increasing attention worldwide due to the relationship between food safety and human health problems. In this work, a visible-light-driven photoelectrochemical (PEC) OTC aptasensor was constructed using Bi4VO8Cl/nitrogen-doped graphene quantum dots (Bi4VO8Cl/N-GQDs) nanohybrids as photoactive material and OTC aptamer as identification element. Owing to the well matched heterojunction of Bi4VO8Cl and nitrogen-doped graphene quantum dots (N-GQDs), the photogenerated electron hole pairs could be separated effectively, so that the photocurrent intensity of as-prepared Bi4VO8Cl/N-GQDs nanohybrids was about 7 times higher than pure Bi4VO8Cl and had higher stability. The constructed "signal-off" PEC aptasensor realized OTC detection in tomato samples with excellent sensitivity, specificity and repeatability. The photocurrent decreased with the increase of OTC concentration in a range from 0.1 nM to 150 nM, and the detection limit was 0.03 nM (S/N = 3). The national standard method was used to compare with our method and the results were consistent.

Volume:398

Translation or Not:no