Encoding CsPbX perovskite quantum dots with different colors in molecularly imprinted polymers as fluorescent probes for the quantitative detection of Sudan I in food matrices.

All-inorganic cesium lead halides (CsPbX, X  = Cl, Br, I) perovskite quantum dots (PQDs) have attracted extensive research attention due to their unique optical properties. However, their instability and sensitivity to air and moisture hinder further use in fluorescent sensing applications. In this work, the construction and application of PQDs encoded molecularly imprinted polymers (MIPs-CsPbX) for Sudan I detection were proposed. After being encoded the PQDs, the obtained MIPs-CsPbX microspheres exhibited high stability for the external environment, remarkable bright fluorescence, and specific recognition for Sudan I. The fluorescent intensity of the MIPs-CsPbX microspheres was obviously quenched upon loading Sudan I, and good linear responses in the range of 0.5-150 µg L, limit of detection of 0.3 µg L, and good recoveries of 95.27 % to 105.96 % in spiked samples were obtained. The developed fluorescent probe provided a selective and sensitive quantified method for Sudan I detection in food matrices.