Development of High Quarity of Chemical Sensors Based on Polymeric Thin Film Coating

聚合物包覆电极（pce）由金属或碳导体直接包覆一层离子敏感、电催化或酶膜组成，与传统的膜电极相比，由于其操作简单、优越的安培响应特性、最小化能力等优点，是非常有吸引力的电位和安培传感器。本研究制备了一种基于双层膜涂层的葡萄糖和胆固醇传感器，并对其在稳态条件下的传感器特性进行了研究。通过测量H_2O_2或O_2电催化还原膜的电流，可以监测葡萄糖或胆固醇的浓度。被外膜酶反应所消耗。获得了葡萄糖或胆固醇浓度与传感器输出之间可重复的关系。pce作为一种电化学检测器，可用于流动注射分析。由于带正电荷的电聚合膜与分析物之间存在静电相互作用，导致流动注射系统的静电测量检测的选择性有很大的提高，即阳离子物质（如多巴胺、1-去甲肾上腺素和dl - 3,4 -二羟基苯基丙氨酸）几乎没有反应，而中性和阴离子物质(如3,4 -二羟基苯基乙酸、4-羟基-3-甲氧基苯基乙酸和儿茶酚)在聚合物包覆电极上与裸电极相比变化不大。在覆盖每个振荡器系统谐振频率区域的频率范围内，对有薄膜涂层和没有薄膜涂层的石英晶体振荡器进行了复杂导纳测量（即电导与频率图和电纳与频率图）。石英晶体振荡器与不同浓度的空气、水分和支撑电解质水介质接触。根据传统的压电石英晶体等效电路模型，对相关电路参数（电阻R、电感L、电容C和静态电容C_0）进行了计算，特别是作为支撑电解质浓度的函数。通过评价的参数表征了电解质浓度对膜溶胀的影响。结果表明，所述方法可以应用于有机、无机和生物薄膜的运动粘度和亲和感测。石英晶体微天平（QCM）在液体中工作时保持其高质量灵敏度。因此，QCM已被应用于聚合物薄膜氧化还原过程中发生的质量变化。在用聚二茂铁、聚苯胺等薄膜修饰电极的情况下，定性地证明了在电中性过程中溶剂传输需要离子传输。少

Polymer coated electrodes (PCEs), which consist of a metallic or carbon conductor direct coated with an ion-sensitive, electrocatalytic, or enzyme membrane, are very attractive potentiometric and amperometric sensors due to their simplicity of operation, superior amperometric response characteristics, capability of minimization, etc., compared with conventional membrane electrodes.In this research, new amperometric sensors for determination of glucose and cholesterol based on bilayer film coating have been fabricated and their sensor characteristics under a steady-state condition have been examined. The glucose or cholesterol concentration could be monitored by measuring the current for H_2O_2 or O_2 reduction electrocatalyzed inner film where H_2O_2 was produced orO_2. was consumed by the enzyme reaction in the outer enzyme films. The reproducible relationship between glucose or cholesterol concentration and sensor output was obtained. The PCEs functioned as an electrochemical detecto … More r for flow injection analysis. Substantial unprovement in the selectivity of arnperometric detection for flow injection system was observed as a result of an electrostatic interaction between the positively charged electropolymerized film and analysis, that is, cationic species (e. g., dopamine, 1-norepinephrine and DL-3, 4-dihydroxyphenylalanine) exhibited little response, while the response of neutral and anionic species (e. g., 3, 4-dihydroxyphenylacetic acid, 4-hydroxy-3-methoxyphenylacetic acid and catechol) was only slightly changed at the polymer coated electrode compared with the bare electrode.The complex admittance measurements of the quartz crystal oscillators with and without a film coating, which are in contact with air, moisture and supporting electrolyte aqueous media of various concentrations have been carried out over a frequency range covering the area of the resonant frequency of each oscillator system, and the results have been represented in the form of conductance and susceptance spectra (i. e., conductance vs. frequency plots and susceptance vs. frequency plots). According to the electrical equivalent circuit model conventionally proposed for a piezoelectric quartz crystal, the related circuit parameters (resistance R, inductance L, capacitance C and static capacitance C_0) have been evaluated, especially as a function of the concentration of supporting electrolyte. The change of electrolyte concentration-dependent swelling of the film was characterized by the evaluated parameters. It is demostrated that the method described can can apply the characterized kinematic viscosity and affinity sensing of the organic, inorganic and biological thin films. The quartz crystal microbalance (QCM) when operated in liquids was shown to retain its high mass sensitivity. The QCM has therefore been applied to the mass changes occurring during redox in thin polymer films. Solvent transport during electroneutrality requiring ion transport has been qualitatively demonstrated in the case of electrodes modified with thin film of poly (vinyferrocene), polyaniline, etc. Less