A fluorescence-assisted SERS aptasensor based on gold nanoflowers for sensitive detection of alternariol

Alternariol (AOH) is a secondary toxin produced by the metabolism of Alternaria, which poses a significant food safety risk due to its widespread presence in fruits and vegetables. In this study, a dual-mode sensor based on AOH aptamer was developed, which combined with surface-enhanced Raman scattering (SERS) and fluorescence (FL) detection technology to achieve sensitive and specific detection of AOH. The sensor significantly improves the reliability of detection through the synergistic change and mutual verification of SERS and FL signals. The linear detection range of SERS mode was 0.5–100 ng/mL ( R 2  = 0.9927), and the detection limit was as low as 0.064 ng/mL. The linear range of FL mode was 1–100 ng/mL ( R 2  = 0.9792), and the detection limit was 0.14 ng/mL. Experiments showed that the sensor could effectively distinguish AOH from other mycotoxins, and showed good recovery (SERS: 84.09 % -101.40 %, FL: 4.69 % -105.57 %) and precision (RSD < 6.3 % and 8.9 %, respectively) in complex matrices such as kiwifruit, tomato and citrus. The results were consistent with those of the traditional LC-MS method, which verified its reliability. The sensing platform constructed in this study not only provides a reliable technical means for the trace detection of AOH in agricultural products, but also opens up a new way for the rapid screening and quantitative analysis of other mycotoxins in food matrices.