Fluorometric kinetic determination of aflatoxin B1 by combining Cd-free ternary quantum dots induced photocatalysis and chemometrics

Abstract

Upon exposure to Reactive Oxygen Species (ROS), Aflatoxin B1 undergone the formation of a highly fluorescent derivative, which was exploited to develop a straightforward methodology for the determination of AFB1 in food samples. Cd-free AgInS2 ternary quantum dots were used as ROS generators, upon visible light irradiation, and kinetic photoluminescence data (PL) collected throughout AFB1 photocatalysis was used to build-up a second-order dataset seeking to overcome selectivity issues related to QDs non-specific reactivity. The use of a flexible multivariate calibration model, as is the case of U-PLS/RBL, allowed to extract useful information from the PL dataset and enabled to achieve the second-order advantage making possible to accurately determine AFB1 even in the presence of unknown interfering species not included in the calibration set. The developed approach allowed the accurate quantification of AFB1 in rice samples at concentration levels in conformity with the EU regulation.