A fluorescent aptasensor based on nitrogen-doped carbon supported palladium and exonuclease III-assisted signal amplification for sensitive detection of AFB1

Aflatoxin B1 (AFB(1)) has strong carcinogenicity and toxicity, so it is necessary to develop a highly sensitive detection method. In this paper, a novel nitrogen-doped carbon supported palladium (C-N-Pd) material was synthesized and firstly used as the energy receptor for fluorescent aptasensor. Using C-N-Pd as a novel quenching material and exonuclease III (Exo III) as assisted signal amplification, a fluorescent aptasensor for AFB1 detection was constructed. Compared with the sensor without enzyme, the fluorescence intensity obtained by the sensor with Exo III increased by 74.7%. The fabricated fluorescent aptasensor exhibited a good selectivity toward AFB1 with a limit of detection (LOD) as low as 9 pg mL(-1). Moreover, the designed aptasensor was successfully utilized to detect AFB1 in spiked corn, peanut and wine samples, and the LOD is 15 pg mL(-1), 13 pg mL(-1) and 18 pg mL(-1), respectively. In addition, the aptasensor was also compared with HPLC method, and the good agreement was found between them.

Automated summary

A novel nitrogen-doped carbon supported palladium material (C-N-Pd) was synthesized and used in constructing a fluorescent aptasensor for AFB1 detection. The aptasensor exhibited high sensitivity and good selectivity towards AFB1, and successfully detected the toxin in contaminated food samples. The aptasensor showed good agreement with the HPLC method, indicating its potential as a reliable detection tool for AFB1.