Design And Synthesis Of MOFs Magnetic Composites And Their Application In Separation And Concentration Of Polar Antibiotics

Antibiotics are a class of secondary metabolites produced by microorganisms or higher plants and animals that have anti-pathogens or other activities during their lives.It has been widely used in the treatment of various diseases in humans and animals.Most antibiotic drugs taken by humans and animals cannot be fully absorbed and used,but are discharged into the sewage through excretion and other methods to enter the environment and the food chain.Various sewage treatment processes have little or no effect on antibiotic drugs,and enter the environment and Antibiotics in the food chain will pose a potential threat to the safety of humans and the ecological environment.Therefore,it is necessary to analyze and test antibiotics in food and the environment.Since antibiotics are usually present in trace amounts or trace amounts in food and environment,they need to be enriched and separated before testing.Adsorption is an efficient and economical separation and enrichment method.The most important thing for adsorption technology is to select the appropriate adsorbent.Metal-Organic Frameworks?MOFs?are a class of materials with adjustable pore size formed by self-assembly of organic ligands and metal centers.They have a porous structure,a large specific surface area,and many adsorption sites.Fe₃O₄ magnetic microspheres with high paramagnetism are introduced into the MOFs material,and the synthesized MOFs magnetic composite material can achieve rapid and simple extraction separation under the action of an external magnetic field.These properties make MOFs magnetic composite materials have the potential to become efficient antibiotic adsorbents.In this paper,with the target of tetracycline antibiotics?Tetracycline antibiotics,TCs?and penicillin antibiotics?Penicillin antibiotics,PCs?,two MOFs magnetic composite materials were studied as adsorbents to enrich and separate these antibiotics.The main contents are as follows:?1?:Fe₃O₄@[Cu₃?btc?₂]was synthesized and used as an adsorbent to establish a magnetic micro-solid phase extraction system,combined with liquid chromatography-tandem mass spectrometry?liquid chromatography-tandem mass spectrometry,LC-MS/MS?was used to detect 4 polar TCs antibiotic residues in drinking water samples and environmental water samples.The synthesized Fe₃O₄@[Cu₃?btc?₂]was characterized.The effects of p H,extraction time and other conditions on the extraction efficiency were investigated,and the adsorption mechanism of Fe₃O₄@[Cu₃?btc?₂]to four tetracycline antibiotic drugs were discussed.The detection limit of this method is 0.01?0.02?g/L,and the limit of quantification is 0.04?0.07?g/L.The addition recovery rates in river water and aquaculture water samples were 82.4%?96.5%and 70.3%?91.4%,respectively.The amount of adsorbent is only 10 mg,and the enrichment factor is 25.Fe₃O₄@[Cu₃?btc?₂]microextraction combined with LC-MS/MS is applied to the extraction and detection of 4 polar TCs in environmental water samples,and satisfactory recovery and sensitivity can be obtained.?2?Fe₃O₄@ZIF-67 was synthesized and used to adsorb PCs antibiotics in drinking water samples and environmental water samples,combined with LC-MS/MS to detect residual PCs in water.The synthesized Fe₃O₄@ZIF-67 was characterized.The effects of the amount of adsorbent,reaction time and p H during the adsorption of PCs by Fe₃O₄@ZIF-67 were studied.The detection limit of this method is 0.01?0.06?g/L,and the limit of quantification is 0.03?0.19?g/L.At three concentration levels of 0.1,1.0and 10.0?g/L,the recovery rates of the 6 PCs in river water and culture water samples were 79.2%?96.6%and 75.9%?94.8%,respectively.Fe₃O₄@ZIF-67 micro-solid phase extraction combined with LC-MS/MS can be successfully applied to the extraction and detection of 6 PCs in water samples.Fe₃O₄@ZIF-67 micro-solid phase extraction combined with LC-MS/MS can be successfully applied to the extraction and detection of 6 polar PCs in water samples.