【作者】 张芬芬；

【导师】 丁亚萍；

【作者基本信息】 上海大学 ， 钢铁冶金， 2013， 博士

【摘要】 抗菌类药物是人类在医药领域取得的最伟大成就之一，对人类健康水平的提高和生命安全的保障起到了极其重要的作用。抗菌类药物广泛地应用于临床、兽药、农业等方面，对人类的生产生活具有巨大的促进作用。然而随着人类对抗菌类药物所引起的耐药性以及在动物性食品中的残留对人体的危害问题的持续关注，抗菌类药物滥用的问题已经引起了研究人员的浓厚兴趣，研究者们开始致力于开发研究分析测定方法来检测抗菌类药物的含量以及研究动植物体内药物残留的问题。目前已有报道的测定该类药物的分析手段有很多种，而电化学方法因其具有简单、灵敏、响应快、成本低等优点，在该类药物的分析中成为了新的研究热点。本论文主要研究了抗菌类药物电化学传感器的构建和性能、探索了电化学行为和电极反应机理，从而建立了一系列灵敏、简单、准确的定量分析方法。主要内容归纳如下：1.首次制备了磺基丙氨酸修饰碳糊电极用于氧氟沙星和加替沙星的同时测定。利用循环伏安法成功地将半胱氨酸氧化成磺基丙氨酸修饰到碳糊电极表面，通过傅里叶变换红外光谱和电化学阻抗谱的表征证明了磺基丙氨酸膜已经成功地修饰在碳糊电极表面，并且该膜可以有效地降低修饰电极的阻抗以及加速分析物和电极之间的电子传递速率。同时利用循环伏安法研究了该修饰电极对氧氟沙星和加替沙星的催化性能。研究表明磺基丙氨酸膜修饰电极与裸电极相比，不仅使分析物氧氟沙星和加替沙星的电位分开116mV，更使分析物氧氟沙星和加替沙星的氧化电流增大了5倍，十二烷基苯磺酸钠的出现则可以把氧氟沙星和加替沙星的电流进一步增加到8倍，从而实现同时测定。实验结果表明，氧氟沙星和加替沙星的氧化电流与其浓度之间的线性范围分别为0.06–10μM和0.02–200μM，对应的检出限分别为0.02μM和0.01μM。此外将该修饰电极用于实际药品和血清中氧氟沙星和加替沙星含量测定，结果令人满意。此电化学生物传感器为同时测定氧氟沙星和加替沙星提供了一种非常便利的方法。2.首次制备了基于β-环糊精和L-精氨酸聚合物修饰电极的喹诺酮类药物电化学传感器。该传感器利用了β-环糊精和L-精氨酸的协同作用来检测喹诺酮类药物。扫描电镜表征图证明β-环糊精和L-精氨酸聚合物膜已经成功地聚合在碳糊电极表面。阻抗图和循环伏安图进一步证实了β-环糊精和L-精氨酸聚合物膜有效地降低了电极的电子转移电阻并且促进了被测物和电极之间的电子转移动力。在最佳条件下，该修饰电极用来测定环丙沙星、氧氟沙星、诺氟沙星和加替沙星。差分脉冲伏安图显示被测物的氧化电流随着其浓度的增大呈现线性关系，线性范围分别为：环丙沙星0.05–100μM，氧氟沙星0.1–100μM，诺氟沙星0.1–40μM，加替沙星0.06–100μM。该传感器还被用来测定实际药片和血清中喹诺酮类药物的含量,并取得了令人满意的结果。3.构建了基于Au纳米粒子和聚精氨酸修饰电极的头孢噻肟电化学传感器。通过扫描电镜图和傅里叶变换红外光谱图证明L-精氨酸已经聚合到电极表面，从扫描电镜图上还可以看到电沉积上的Au纳米粒子呈球状结构。电化学阻抗图和循环伏安图进一步说明了Au纳米粒子/聚精氨酸膜有效地提高了电极表面的电子转移速率。头孢噻肟在修饰电极上的电化学氧化是通过循环伏安图和线性循环伏安图来展示的。结果得到，与裸电极相比，头孢噻肟在修饰电极上的氧化峰电流提高了17倍，说明了该修饰电极能够应用到头孢噻肟的定量测定中。电极上的峰电流与头孢噻肟的浓度之间呈现出良好的线性关系。线性范围为0.01–100μM，最低检出限为2.3nM。4.构建尿嘧啶共价键合修饰碳糊电极用于定量测定抗艾滋病药物奈韦拉平。通过电化学沉积将尿嘧啶修饰到电极表面，利用电化学交流阻抗和循环伏安法证实了尿嘧啶已经共价键合到电极上，并且有效地提高了电极的电子转移速率。奈韦拉平在修饰电极上的电化学现象主要是通过循环伏安法和差分脉冲伏安法进行考察的。考察了支持电解质的pH和扫速对被测物氧化峰的影响，从而得知奈韦拉平在电极上的反应为吸附控制过程。在最佳条件下，奈韦拉平的氧化峰电流与浓度之间呈现良好的线性关系。线性范围为0.1–70μM，该电极对被测物的灵敏度为2.073μA mM-1cm-2(S/N=3)。5.制备了一种基于手性聚吡咯修饰玻碳电极手性识别丙氨酸对映体的电化学传感器。该手性聚吡咯是利用L-丙氨酸阴离子表面活性剂作为模板分子合成的，表征结果也显示了该手性聚吡咯具有手性结构。将该修饰电极应用到丙氨酸对映体的定量检测中，取得了良好的结果。证实了利用电化学传感器识别手性对映体分子的可能性。更多还原

【Abstract】 Antibiotics are one of the great achivement of the human. They hold an importentrole in human healthy and safity. Antibiotics have been widely used to treat peopleand animal diseases and promote animal growth. However, the misuse of thesemedicines may have some adverse affects, such as allergic reactions and antibioticresistance. Therefore, sensitive and selective methods for their determination inbiological fluids are highly advisable. A series of analytical methods have beenreported for the determination of antibiotics.Among these methods, electrochemicalmethod has been widely accepted due to the advantages of considerable simplicity,quick response and low cost. The electrochemical sensors are used to study theelectrochemical propoties and electrode reaction mechanism and thereupon establishselective, simple and precise quantification analytical method. In this paper, weprepared different modified electrodes for the analysis of antibiotics includingofloxacin, norfloxacin, ciprofloxacin, gatifloxacin, cefotaxime and nevirapine, whichhas been summarized as follows:1. A novel cysteic acid modified carbon paste electrode (Cysteic acid/CPE) based onelectrochemical oxidation of L-cysteine was developed to simultaneously determineofloxacin and gatifloxacin in the presence of sodium dodecyl benzene sulfonate(SDBS). Fourier transform infrared spectra (FTIR) indicated that L-cysteine wasoxidated to cysteic acid. Electrochemical impedance spectroscopy (EIS) and cyclicvoltammograms (CV) indicated that cysteic acid was successfully modified onelectrode. The large peak separation (116mV) between ofloxacin and gatifloxacinwas obtained on cysteic acid/CPE while only one oxidation peak was found on bareelectrode. And the peak currents increased5times compared to bare electrode.Moreover, the current could be further enhanced in the presence of an anionicsurfactant, sodium dodecyl benzene sulfonate. The differential pulse voltammograms(DPV) exhibited that the oxidation peak currents were linearly proportional to their concentrations in the range of0.06–10μM for ofloxacin and0.02–200μM forgatifloxacin, and the detection limits of ofloxacin and gatifloxacin were0.02μM and0.01μM (S/N=3), respectively. This proposed method was successfully applied todetermine ofloxacin and gatifloxacin in pharmaceutical formulations and humanserum samples.2. An electrochemical sensor for fluoroquinolones (FQs) based on polymerization ofβ-cyclodextrin (β-CD) and L-arginine (L-arg) modified carbon paste electrode (CPE)(P-β-CD-L-arg/CPE) was built for the first time. Synergistic effect of L-arg andβ-CD was used to construct this sensor for quantification of these importantantibiotics. Scanning electron microscope (SEM) image shows that polymer of β-CDand L-arg has been successfully modified on electrode. Electrochemical impedancespectroscopy (EIS) and cyclic voltammograms (CV) further indicate that polymer ofβ-CD and L-arg efficiently decreased the charge transfer resistance value ofelectrode and improved the electron transfer kinetic between analyte and electrode.Under the optimized conditions, this modified electrode was utilized to determinethe concentrations of ciprofloxacin, ofloxacin, norfloxacin and gatifloxacin. Thedifferential pulse voltammograms (DPV) exhibits the oxidation peak currents werelinearly proportional to their concentration in the range of0.05–100μM forciprofloxacin,0.1–100μM for ofloxacin,0.1–40μM for norfloxacin and0.06–100μM for gatifloxacin, respectively. This method was also successfully used todetect the concentrations of each drug in pharmaceutical formulations and humanserum samples. In addition, this proposed fluoroquinolones sensor exhibited goodreproducibility, long-term stability and fast current response.3. A simple and sensitive electrochemical sensor based on Au nanoparticles/poly(L-arginine) modified carbon paste electrode (AuNPs/Parg/CPE) was constructedand utilized to determine cefotaxime. Scanning electron microscope (SEM) imageshowed that the L-arginine (L-arg) had been electropolymerized on the CPE and theimmobilized Au nanoparticles (AuNPs) were spherical in shape. Fourier transform infrared spectra (FTIR) indicated that the Poly (L-arginine)(Parg) film wassuccessfully modified on CPE. Electrochemical impedance spectroscopy (EIS) andcyclic voltammogram (CV) illustrated the Parg and AuNPs efficiently decreased thecharge transfer resistance value of electrode and improved the electron transferkinetic between analytes and electrode. The electrooxidation of cefotaxime on themodified electrode was performed by cyclic voltammetry (CV) and linear sweepvoltammetry (LSV). The results showed the response current of cefotaxime atAuNPs/Parg/CPE increased17times than that of bare CPE. The calibration curvewas linear over the cefotaxime concentration range of0.01–100.0μM with adetection limit (S/N=3) of2.3nM. This proposed method has been applied todetermine cefotaxime in pharmaceutical formulations and human serum samples,and the results were satisfactory.4. A novel uracil covalently grafted carbon paste electrode (Ura/CPE) based onelectro-deposition of uracil on CPE was prepared for the quantitative determinationof nevirapine. The records of electrochemical impedance spectroscopy (EIS) andcyclic voltammograms (CV) in K3Fe(CN)6/K4Fe(CN)6solution illustrated that uracilgrafted on CPE efficiently decreased the charge transfer resistance value of electrodeand improved the electron transfer kinetic between analyte and electrode. Theelectrochemical properties of Ura/CPE towards the oxidation of nevirapine wereinvestigated by cyclic voltammetry and differential pulse voltammetry (DPV) in0.1M NaOH. The effects of pH and scan rates on the oxidation of nevirapine werestudied. The results indicated the participation of the same protons and electrons inthe oxidation of nevirapine, and the electrochemical reaction of nevirapine onUra/CPE is an adsorption-controlled process. Under optimized conditions, thelinearity between the oxidation peak current and nevirapine concentration wasobtained in the range of0.1–70.0μM with detection limit of0.05μM and thesensitivity of2073μA·mM–1·cm–2(S/N=3). The proposed method was alsosuccessfully applied to detect the concentration of nevirapine in human serum samples.5. A new chiral recognition of alanine enantiomers sensor was built based on chiralmesopores polypyrrole modified on glass carbon electrode. chiral mesoporespolypyrrole was prepared by using N-myristoyl-L-alanine to be chiral lipid ribbontemplating and "seeding" route. SEM image illustrated the the morphology of chiralmesopores polypyrrole was helical structure. This material was modified on theelectrode to recognize the alanine enantiomers in solution. The result wassatisfactory.更多还原