【作者】 刘镇；

【导师】 高志贤；

【作者基本信息】 华中农业大学 ， 微生物学， 2010， 硕士

【摘要】 分子印迹聚合物(Molecularly imprinted polymers,MIPs)是一种高分子聚合物,通过模板分子印迹到聚合物表面并被洗脱,使聚合物表面留下可以结合模板分子的孔洞,这些孔洞具有再吸附模板分子的能力。分子印迹物具有从多种组分中选择性识别目标分子或与其结构相近的某一类化合物的能力。由于分子印迹聚合物的化学性能稳定,目前已经广泛应用于固相萃取、缓释胶囊、模拟生物酶、仿生传感器检测等领域。压电生物传感器是一种通过把生物信号转化为电信号输出的传感器,具有灵敏度高,响应快速,操作简单等优点。较为常用的有石英压电微天平传感器(QCM),通过电极表面质量的变化引起石英片振动频率的改变,通过软件将这种频率改变量记录输出,通过这种方法达到测定微小质量改变的目的。向电极表面加载抗体,酶等生物活性材料,可以用于食品农兽药残留的检测中。但抗体和酶有制备周期长,抗极端环境性差等缺点,人工抗体——分子印迹聚合物可以成为抗体和酶的替代材料作为传感器的识别部件。本研究利用计算机软件(HyperChem 8.0)模拟、紫外光谱分析对模板分子与功能单体之间的作用机理进行表征,对分子印迹聚合物的可行性进行预测。采用热引发沉淀聚合的方法,以克百威、莱克多巴胺、对硫磷、氯霉素为模板分子,成功地制备了可选择性识别克百威、莱克多巴胺、对硫磷和氯霉素的分子印迹聚合物微球。根据引发剂加入量不同,观察聚合物粒径,产率,吸附量等性质的影响。对聚合物的物理性质进行分析,结果显示合成的微球形状规则,粒径均一,粒径范围在1μm左右。对吸附特性利用平衡吸附进行了研究,并进行数学计算,最终推断出印迹聚合物的最大吸附量Qmax和平衡解离常数KD。克百威Qmax=2.3μmol/g;莱克多巴胺8.8μmol/g;对硫磷KD=91.7μmol/L,最大吸附量Qmax=3.92μmol/g。在此研究工作基础之上,我们还完成了对硫磷和氯霉素分子印迹聚合物在石英压电微天平的固定方法的研究,以聚氯乙烯(PVC)为包埋材料,以四氢呋喃(THF)为溶剂,将对硫磷和氯霉素的分子印迹聚合物微球固定在石英压电微天平电极上。对如涂布量、背景溶液乙腈和磷酸缓冲液组成等条件进行优化和实验。传感器进行了初步的应用实验,得出了虾肉和猪肝中氯霉素残留的传感器检测结果,并对传统检测方法的实验数据进行了对比,灵敏度和回收率均比较理想。本研究为制备可以应用现场的、实时的、快速的食品安全检测方法样品快速处理和生物传感器方法建立提供了理论依据和实际指导。更多还原

【Abstract】 Molecularly Imprinted Polymers(MIPs) is a kind of high polymer based on the antigen-immune body reaction principal, and synthesis by chemistry method, which is also called "the artificial immune body". The molecular imprinted polymers has the ability that selective the target from many kinds of components. Because that the chemical properties of molecular imprinted polymers are stable, at present, molecular imprinted polymers are already widely applied in sample separation, solid phase extract and biological sensor examination.Traditional preparation method of Molecularly imprinted polymer is corpus polymerization, which needs to undergo the attrition and screening, so the preparation process is complex, moreover the obtained grain shape is anomalous, and the recognition efficiency is low. And because uses aerosol, the emulsion polymerization obtained polymer microballoons to include the surface active agent, the post-processing working procedure is complex, and has certain influence to the signature polymer’s adsorption performance, thus has limited its application domain. There are many advantage of precipitates polymerization, for example, the equipment is simple, the signature particle size is homogeneous, specific surface area is bigger than the one by tranditional method, which is high-performance in the signature adsorption.By piezoelectric biosensor is a biological signal into an electrical signal to the output of the sensor with high sensitivity, fast response, simple operation.The more commonly used piezoelectric quartz microbalance sensor (QCM), surface quality through the electrode to changes in the vibration frequency of quartz changes the frequency by changing the amount of software that records the output, measured by this method to achieve the purpose of small change in the quality.Load to the electrode surface antibodies, enzymes and bio-active material, can be used for pesticide and veterinary drug residues in food detection.But the antibody and the enzyme preparation cycle length, and poor resistance to extreme environmental drawbacks, artificial antibodies-molecular imprinted polymer antibodies and enzymes can be an alternative material as sensor, and components.In this study, Carbofuran, Parathion, Ractopamine and Chloramphenicol are as the research object, synthesis of molecular imprinted polymers, and to explore building a piezoelectric quartz microbalance sensor (QCM) method. Computer software (HyperChem 8.0), UV spectra are used to character the action mechanism of template molecule and functional in order to predict the feasibility of molecular imprinted polymers. In the experiment, we add different amount of initiator to observe the polymer properties. The physical properties of the polymer using environmental scanning electron microscope analysis showed that the synthesis of micro-ball shape of rules, uniform particle size, particle size is about 300nm.Equilibrium adsorption and mathematical model are used to deduce the maximum adsorption capacity of imprinted polymer (Qmax) and the equilibrium dissociation constant (KD).Scatchard analysis is used to analysis the imprinted materials binding site.Use the template molecule analogues on molecularly imprinted polymers selective adsorption analysis showed that there is a high specificity of molecular adsorption. The data shows that the method of molecular imprinted polymer synthesized meets the requirements, and may be used in pesticide and veterinary drug enrichment.Based on the work of this study, we have also make parathion and chloramphenicol molecularly imprinted polymer be fixed on the quartz crystal microbalance.The PVC and tetrahydrofuran (THF) were as the embedding material and solvent. Detect conditions, such as coating weight and the background solution were estimated to optimize the composition and experimentation. We carried out a preliminary application of experiments obtained detector of chloramphenicol residues in shrimp and liver,and the data were compared with traditionary detection method, which certified that the MIP-QCM method is a sensitive method in pesticide and veterinary drug detection, and faster, cheaper than ELISA and chromatograph.This study gives us some helpful method and theory in real-time, on-spot, fast detection of pesticides and veterinary drugs residue in foodstuff.更多还原