Carbon dot embedded photonic crystal molecularly imprinted as dual-mode fluorometric/colorimetric sensor for the determination of sulfadimethoxine in fish

Abstract

A novel fluorescent membrane based on carbon dot embedded photonic crystal molecularly imprinted polymer ([email protected]) was developed for fluorometric and colorimetric dual-mode determination of sulfadimethoxine with excellent selectivity, quick response, and reusability. In the presence of sulfadimethoxine, fluorescence quenching and red shift of diffraction peak from [email protected] were observed because of the photo-induced electron transfer and structural change of [email protected], accompanied by a visual color change from blue to green. The fluorescence quenching efficiency and the red-shift of the diffraction peaks were positively correlated with the logarithms of the sulfadimethoxine concentration at 10-12–10-5 and 10-10–10-5 mol L-1, respectively. The sensor achieved a limit of detection of 0.08 pmol L-1 (fluorescence method) and 2.75 pmol L-1 (colorimetric method, 3σ, n=9). The developed [email protected] membrane was applied for the detection of sulfadimethoxine in fish samples with favorable recovery of 84.8%–102.9%.