【作者】 魏晓兵；

【导师】 许鑫华；

【作者基本信息】 天津大学 ， 材料学， 2017， 博士

【摘要】 磺胺类药物（Sulfonamides,SAs）在动物源食品中的过量残留对人体健康造成很大威胁,而且由于动物源食品是个复杂体系,SAs残留含量低、干扰物质多,造成检测难度非常大。因此,如何从复杂样品中分析痕量的SAs残留,开展建立SAs残留的高效前处理方法和快捷、准确的分析检测技术具有重要的研究意义和实际应用价值。本文主要研究内容如下:利用沉淀聚合法制备分子印迹聚合物/氧化石墨烯复合材料MIP/GO,并将其作为一种新型分子印迹固相萃取吸附剂。该材料对磺胺二甲嘧啶SM2的吸附量是传统MIP吸附量的1.5倍,可以实现痕量物质的有效富集。结合液相色谱法对SM2残留进行检测,方法回收率为90.55%-103.20%,相对标准偏差为3.36%-5.33%。这种前处理方法简单、快捷,能有效排除杂质的干扰,提高萃取效率。以聚苯乙烯PS为模板分子,利用硬模板法和溶胶凝胶技术合成PS@SiO₂,并通过高温烧结去除PS模板分子制备空心SiO₂微球,作为一种新型色谱固定相填料。该材料结构规整,直径为2μm,比表面积为511 m²/g,柱效可达43000 N/m,分离度良好,在普通液相色谱使用中实现了高柱效、低柱压的性能,具有一定的应用价值。扩展色谱塔板理论的应用,结合计算机技术,建立保留时间和色谱峰形的预测模型,实现对多种磺胺类药物的优化分离。在18种梯度洗脱条件下,对13种磺胺类药物进行色谱保留时间、色谱峰形及不同流速下色谱行为的预测,验证新模型的可行性和可靠性。该方法的平均绝对偏差MAD为1.59%,平均相对偏差MRD为-0.27%,预测精度高,从而为建立磺胺类药物的最优化分离方法奠定基础。利用表面分子印迹技术制备还原氧化石墨烯/分子印迹聚合物复合材料rGO/MIP,构建一种新型的电化学传感器。该传感器印迹位点位于印迹材料表层,提高了对SM2的识别响应速度、吸附性和选择性。线性范围为0.5-500ng/m L,检出限为0.287 ng/mL（S/N=3）,回收率范围为91.85%-104.42%,相对标准偏差为2.51%-4.45%,重现性以及稳定性良好。该方法不需要对样品进行前处理,检测速度快,灵敏度高,可以满足对食品中磺胺类药物残留的检测。利用电聚合方法,以SM2为模板分子,吡咯为功能单体,构建基于3D石墨烯的分子印迹NiCo₂O₄阵列传感器。该分子印迹阵列传感器拥有三维结构、具有更多的有效识别位点,无需样品前处理,实现对SM2特异性高灵敏度检测。线性范围为0.2-1000 ng/m L,检出限为0.169 ng/mL（S/N=3）。回收率范围为92.30%-102.23%,相对标准偏差为2.27%-4.10%。此分子印迹阵列传感器进一步增强检测SM2的选择性和灵敏度,扩展了其在食品中磺胺类药物残留的检测应用。更多还原

【Abstract】 Sulfonamides（SAs）as antibiotic drugs are the emerging contaminants closely linked to people’s daily life.The harmful residues of SAs drug originating from food products of animal increase the risk of people’s health.However,many problems such as complicated existence form,low content and various interference lead to numerous errors in the test procedure.Therefore,the studies of pretreatment and detection technology for SAs drug residues in food sample are significant in academic and application.The main work of the article is as follows:Molecularly imprinted polymer/graphene oxide（MIP/GO）as a novel solid phase extraction adsorbent was prepared by precipitation polymerization.The adsorption quantity of MIP/GO was 1.5 times than that of the traditional MIP and it showed high selectivity for the template sulfadimidine（SM2）.The recovery range was90.55%-103.20%and the standard deviation was 3.36%-5.33%by HPLC for the analysis of SM2 in milk.This pre-treatment method was simpler,cleaner extractions and possessed high enrichment efficiency.Hollow silica（SiO₂）spheres as new stationary phase for HPLC were prepared by hard template and sol-gel technology.Polystrene（PS）latex was used as template and was removed from PS@SiO₂ by high temperature sintering.The results indicated that the hollow spheres were uniform with particle diameter of 2μm and the surface area was 511 m²/g.The chromatographic properties were evaluated and the packed column showed low column pressure,high values of efficiency（up to about 43,000N/m）and appropriate resolutions.A theoretical method was established to predict the retention time and peak shapes of sulfonamides under gradient elution in reversed-phase HPLC based on the plate theory.This approach was carried out by the retention prediction of 13 common sulfonamides in 18 kinds of gradient conditions and at different flow rates.The mean absolute deviation was 1.59%and the mean relative deviation was-0.27%which indicates the accurate prediction effect.At last,the method could also realize the optimization of separation for 13 sulfonamides.These results demonstrated that the proposed method for the retention prediction was efficient and reliable.A novel sensitive electrochemical sensor based on a glassy carbon electrode（GCE）modified with reduced graphene oxide/molecularly imprinted polymer（rGO/MIP）was developed.The rGO/MIP was prepared by the surface molecularly imprinted technique in the presence of SM2 as template molecule.The printing sites were located on the surface of the imprinted material,which could promote the response speed,adsorption and selectivity to SM2 in food sample.Under optimized conditions,the sensor had a wide linear range over SM2 from 0.5 to 500 ng/mL with a detection limit of 0.287 ng/mL（S/N=3）.The recovery range was 91.85%-104.42%and the standard deviation was 2.51%-4.45%.The sensor displays good stability,reproducibility,and does not require pre-processing of the sample,which can be further applied to quantify SAs drug residues in food with fast detection and high sensitivity.A novel 3D MIP sensor was prepared by electropolymerization of pyrrole as the functional monomer onto NiCo₂O₄ nanoneedle arrays on the 3D graphene in the presence of SM2 as template molecule.The 3D MIP sensor has abundant imprinted sites,need not pretreatment of sample and exhibits high sensitivity and good selectivity for SM2 with three dimensional structure.Under optimized conditions,the sensor had a wide linear range over SM2 from 0.2 to 1000 ng/mL with a detection limit of 0.169 ng/mL（S/N=3）.The recovery range was92.3%-102.23%and the standard deviation was 2.27%-4.10%.The 3D MIP sensor can further enhance the selectivity and sensitivity of SM2 and expand its detecting application for SAs drug residues in food.更多还原