Valorization of a Cr-MOF/polymer composite for the determination of imidacloprid in fish <i>via</i> dispersive solid-phase microextraction

Imidacloprid (IMI) is increasingly prevalent in different environmental segments and has emerged as a possible threat to the ecosystem and human health. Therefore, a sustainable, effective, and eco-friendly approach is necessary for IMI detection. This study reports a new Cr-MOF/polymer composite for the detection of IMI in fish using the dispersive solid-phase microextraction method. This Cr-MOF/polymer composite was synthesized by combining a Cr-MOF with functional monomers, including acrylonitrile and vinyl acetate, to improve the selective absorption of IMI from complex fish sample matrixes. The Cr-MOF/polymer composite was well characterized through SEM, BET analysis, FTIR analysis, and TGA. Kinetics and isotherm analyses suggested that the sorbent's adsorption performance was due to H-bonding. Adsorption data fitted well with the Freundlich model (<i>R</i> ² = 0.991), indicating physisorption, following pseudo-first-order kinetics (<i>χ</i> ² = 1.86, <i>R</i> ² = 0.996). The LOD and LOQ for IMI in fish samples determined through HPLC were 0.004 and 0.012 μg g^-1, respectively. Reusability tests confirmed that the Cr-MOF/polymer composite could be used for over six consecutive cycles. These findings underscore the practical importance of the developed composite in environmental monitoring and enhancing food safety to safeguard public health.