Region separation type bio-photoelectrode based all-solid-state self-powered aptasensor for ochratoxin A and aflatoxin B1 detection

Abstract

Ochratoxin A (OTA) and Aflatoxin B1 (AFB1) are two highly toxic and naturally coexistence mycotoxins, which have posed a serious threat to food safety. The coexistence of these two mycotoxins can produce significant synergistic effects, so it is necessary to establish an effective analytical method. In this work, a dual bio-photoelectrode based all-solid-state multiplexed self-powered aptasensor was realized for high-throughput analysis of OTA and AFB1. There was a large Fermi level difference between photoanode and photocathode, which ensured the light assisted self-driving of the system. Due to the regional immobilization of aptamers, it could save the dosage of recognition elements, reduce the preparation cost and simplify the operation procedure. Meanwhile, construction strategy of spatial separation could effectively eliminate the overlapping signals and cross interference between targets, achieving the results more accurate and the calculation more convenient. The constructed aptasensor realized OTA and AFB1 detection in corn samples with practicality, good stability, anti-interference ability and repeatability. Therefore, this work not only achieved the high-throughput analysis of mycotoxins, but also provided a new perspective for the construction of all-solid-state multiplexed self-powered sensor.