Application Of Novel Composite Materials For Detection Of The Residues Of Three Classes Of Drugs

Food safety issue has always been a hot spot of concern,and the residues of veterinary drugs in animal-derived foods have great potential hazards to consumer’s health.Therefore,the detection of the residues of veterinary drugs in animal-derived foods is very essential to ensure food safety.In recent years,the molecularly imprinted polymer based composites have been used for detection of the residues of veterinary drugs due to their high adsorption capacity and high selectivity.In this experiment,three types of molecularly imprinted polymer based composites for fluoroquinolones,benzimidazoles and sulfonamides were synthesized that were used to develop three sample preparation methods for extraction of the three classes of drugs in foods of animal origin followed by determination with ultra-performance liquid chromatography.In this study,YASARA software was used to simulate and optimize the three dimensional structures of three classes of drugs,and the optimal template molecules were screened out.Firstly,the molecularly imprinted polymer with nalidixic as the template was polymerized on carbonnitride to synthesize a type of new composite.This composite could simultaneously recognize 8 fluoroquinolones with high absorption capacity(15.46-19.42 μg/mg).This composite was used to develop a solid-phase extraction method for extraction and purification of the 8 fluoroquinolones in chicken,followed by detection with ultra-performance liquid chromatography.The limits of detection for the 8 drugs were in a range of 0.2-0.8 ng/g,the recoveries from standard fortified blank chicken muscle samples were in a range of 71.9%-96.8%,and the material could be reused for 20 times.Secondly,the molecularly imprinted polymer with 2-aminobenzimidazol as the template was polymerized on boron nitride to synthesize a type of new material.This composite could simultaneously recognize 7 benzimidazoles with high absorption ability(36.22-38.88 μg/mg).This material was used to develop a dispersive solid phase extraction method for extraction and enrichment of the 7 benzimidazoles in beef,followed by detection with ultra-performance liquid chromatography.This sample extraction method achieved high enrichment factors 21.5-37.9,the limits of detection for the 7 drugs were in a range of 0.2-0.5 ng/g,the recoveries from standard fortified blank samples were in a range of 92.3%-97.1%,and the merterial could be reused for 5 times.Thirdly,sulfadoxine was used as a template to synthesize a type of magnetic molecularly imprinted polymer.This polymer could simultaneously recognize 35 sulfonamides with high absorption capacity(11.01-19.21 μg/mg).This composite was used to develop a dispersive solid phase micro-extraction method for adsorption and enrichment of the 35 sulfonamides in pork,followed by detection with ultra-performance liquid chromatography.This sample extraction method achieved high enrichment factors 22-66,the limits of detection for the 35 drugs were in a range of 0.08-0.53 ng/g,the recoveries from standard fortified blank samples were in a range of 74.2%-96.1%,and the merterial could be reused for 10 times.The three molecularly imprinted polymer based composites have large adsorption capacity,high selectivity and reusability.These materials can be used for the extraction and purification of the residues of veterinary drugs in animal-derived foods.Furthermore these results have a guiding role in promoting the development of new materials and new extraction methods.