3—氯丙基三甲氧基硅烷的合成

采用氯铂酸／异丙醇和三苯基膦／环己酮为催化剂，在室温下能够使三氯硅烷与３－氯丙烯迅速发生硅氢加成反应，高产率地生成３－氯丙基三氯硅烷，继而将３－氯丙基三氯硅烷与无水甲醇同时中到沸腾的石油醚中进行醇解，合成了３－氯丙基三甲氧基硅烷。     

3－氯丙基三甲氧基硅烷的合成

采用氯铂酸／异丙醇和三苯基膦／环己酮为催化剂，在室温下能够使三氯硅烷与３－氯丙烯迅速发生硅氢加成反应，高产率地生成３－氯丙基三氯硅烷，继而将３－氯丙基三氯硅烷与无水甲醇同时滴加到沸腾的石油醚中进行醇解，合成了３－氯丙基三甲氧基硅烷     

纳米金/3-氨丙基-三乙氧基硅烷修饰传感器电化学检测NO-2

将3-氨丙基-三乙氧基硅烷（ATS）修饰在玻碳电极表面,再自组装一层纳米金,制备了一种新型NO2^-的电化学传感器。该修饰电极对NO2^-有较好的催化作用。在pH为3时,NO2^-的氧化峰电流与其浓度在5．0×10^-7～1．0×10^-3mol／L范围内呈良好的线性关系,检出限可达2．0×10^-7mol／L。方法具有较高的灵敏度和较好的重现性。     

2-羟基-3-(三乙胺基)丙基正癸基硫醚修饰碳糊电极测定痕量金

制备了2＿羟基＿3＿(三乙胺基)丙基正癸基硫醚修饰碳糊电极,用于痕量金的测定。研究了电极的伏安特性及分析条件。在0.2mo／LKCl-HCl缓冲溶液中(pH1),Au(Ⅲ)被富集到电极表面,然后介质交换到0.2mol／LKCl-HCl空白溶液中(pH1)进行阳极溶出伏安测定,对于5min富集,Au(Ⅲ)浓度在2×10-8～1×10-6mol／L范围内呈线性关系,检出限为1×10-8mol／L,相对标准偏差5.2%,一般常见离子不干扰。     

丹皮酚在APTS与离子液体复合修饰碳糊电极上的电化学性质及电分析方法

研究了丹皮酚(PN)在3-氨基丙基三氧基硅烷(APTS)与离子液体(［BnMIM］PF6)复合修饰碳糊电极(APTS-［BnMIM］PF6/CPE)上的电化学行为和电化学动力学性质,并用循环伏安法(CV)及计时电流法(CA)测得PN在APTS-［BnMIM］PF6/CPE上的电极反应动力学参数。实验结果表明,PN在APTS-［BnMIM］PF6/CPE上发生了受扩散控制的不可逆电化学氧化过程。用方波伏安法(SWV)测得PN氧化峰电流与其浓度在9.0×10-7~2.0×10-4 mol?L-1和3.0×10-4~1.5×10-3 mol?L-1范围内呈良好线性关系,检出限(LOD,S/N=3)和定量下限(LOQ,S/N=10)分别为3.5×10-8 mol?L-1和1.2×10-7 mol?L-1。同时运用该方法对丹皮酚注射液中PN含量进行了电化学定量测定,其RSD为0.58%~2.4%,加标回收率为96.0%~102.0%。     

呋塞米在APTS与石墨烯复合修饰碳糊电极上的电化学行为及电分析方法研究

研究了呋塞米(FUR)在3-氨基丙基三氧基硅烷(APTS)和石墨烯(RGO)复合修饰碳糊电极(APTSRGO/CPE)上的电化学行为。实验结果表明,与CPE相比,APTS-RGO/CPE对呋塞米的电化学氧化显著增强,其氧化峰电流增加3.4倍。同时采用循环伏安法(CV)、计时电流法(CA)测定了FUR在APTS-RGO/CPE上的电极反应动力学参数,用微分脉冲伏安法(DPV)测得FUR氧化峰电流与浓度的线性范围为1.3~330 mg/L,检出限(LOD,S/N=3)为1.1×10-2mg/L。将该修饰电极应用于市售呋塞米片剂的检测,相对标准偏差(RSD)为0.4%~4.4%,回收率为98.5%~99.7%,检测结果符合电化学定量测定要求。     

3-氨基丙基三甲氧基硅烷自组装提高染料敏化太阳能电池的效率

以3-氨基丙基三甲氧基硅烷(APTS)修饰的二氧化钛为负极制备的染料敏化太阳能电池在100 mW·cm^-2的模拟太阳光照下的短路电流、开路电压、光电转换效率分别为18.32 mA·cm^-2、775.9 mV、9.15%. 而没有经过ATPS修饰的电池三项性能参数分别为18.08 mA·cm^-2、749.9 mV、7.70%, 修饰后电池的光电转换效率提高了18.8%, 同时填充因子由0.57提高为0.64. 暗电流-电压曲线显示起始电压从-0.30 V变化到-0.40 V, 表明二氧化钛电极和电解液之间的暗反应得到了有效抑制, APTS作为阻挡层减少了二氧化钛电极表面的缺陷与表面态. 另外, 通过实验设计, 将APTS与染料层-层自组装于二氧化钛电极上, 通过X射线光电子能谱(XPS)研究了二氧化钛层、APTS、染料的作用形式. 定性与定量结果表明: APTS中的乙氧基部分脱除后形成了Si―O―Ti单桥或者双桥键, 钌染料cis-Ru(dcpyH₂)₂(SCN)₂通过分子中的部分―COOH与APTS中的―NH₂形成的静电作用力吸附在TiO₂电极上. 傅里叶变换红外(FT-IR)光谱的结果进一步证明了这种分子间作用.     

丹皮酚在APTS与离子液体复合修饰碳糊电极上的电化学性质及电分析方法

研究了丹皮酚(PN)在3-氨基丙基三氧基硅烷(APTS)与离子液体([BnMIM]PF6)复合修饰碳糊电极(APTS-[BnMIM]PF6/CPE)上的电化学行为和电化学动力学性质,并用循环伏安法(CV)及计时电流法(CA)测得PN在APTS-[BnMIM]PF6/CPE上的电极反应动力学参数。实验结果表明,PN在APTS-[BnMIM]PF6/CPE上发生了受扩散控制的不可逆电化学氧化过程。用方波伏安法(SWV)测得PN氧化峰电流与其浓度在9.0×10-7~2.0×10-4mol·L-1和3.0×10-4~1.5×10-3mol·L-1范围内呈良好线性关系,检出限(LOD,S/N=3)和定量下限(LOQ,S/N=10)分别为3.5×10-8mol·L-1和1.2×10-7mol·L-1。同时运用该方法对丹皮酚注射液中PN含量进行了电化学定量测定,其RSD为0.58%~2.4%,加标回收率为96.0%~102.0%。     

多巴胺在聚溴甲酚绿修饰碳糊电极上的电化学行为

以碳糊电极(CPE)为基底,采用电聚合方法制备出聚溴甲酚绿修饰碳糊电极(PBG/CPE),运用循环伏安法(CV)对修饰电极进行表征,通过扫描电子显微镜(SEM)对聚合膜的表面形貌进行观察分析。利用PBG/CPE研究了多巴胺(DA)的电化学行为,并对最佳实验条件进行了探讨。研究结果表明:DA在PBG/CPE上于0.32V和0.24V处分别出现一对可逆氧化还原峰,PBG/CPE对DA有显著的催化作用,该催化过程受吸附控制。DA催化氧化还原峰电流与其浓度在1.0×10-5~2.0×10-4mol/L范围内呈现良好的线性关系,检出限为1.0×10-6mol/L。     

巯基硅烷纳米薄膜修饰金电极测定痕量汞(Ⅱ)

采用3-巯丙基三甲氧基硅烷(MPTS)为单一硅源合成有机硅纳米材料,将其组装到金电极表面,制备MPTS薄膜修饰电极。采用原子力显微镜和透射电镜表征有机硅纳米,粒径为3.3~5.7nm;采用方波溶出伏安法测定该修饰电极对汞的响应信号。结果表明,该修饰电极对痕量汞有高灵敏响应。在0.1mol/L HCl中,于-0.4V电位下富集10min,溶出峰电流与其浓度在1.5×10-12~75.0×10-12 mol/L范围内呈线性关系,相关系数为0.9980,检出限为5.0×10-13 mol/L。该方法用于实际水样中汞的测定,与原子荧光光谱法进行比较,结果基本一致。     

Differential Pulse Adsorptive Stripping Voltammetric Determination of Chlorpyrifos at a Sepiolite Modified Carbon Paste Electrode

Abstract

An adsorptive stripping voltammetric (AdSV) method for the determination of organophosphorus insecticide chlorpyrifos at a bare carbon paste electrode (CPE) and clay modified carbon paste electrode (CMCPE) was developed. A systematic study of various experimental conditions, such as the pH, accumulation variables and composition of a modifier on the adsorptive stripping response, were examined by using differential pulse voltammetry. A significant improvement was observed in the sensitivity by using the present method with CMCPE. When CMCPE was used, a linear response was obtained over the concentration range 0.0001–2.0 ppm with lower detection limit of 0.00008 ppm, at an accumulation time of 80 s. The interference from other herbicides and ions on the stripping signal of the compound was also evaluated. The described method was applied to estimate the chlorpyrifos in environmental samples.     

N-乙酰-L-半胱氨酸在咖啡酸修饰碳糊电极上的电催化氧化

研究了N-乙酰-L-半胱氨酸（N-acetyl-L-cysteine,NAC）在咖啡酸（CFA）修饰碳糊电极（CFA/CPE）上的电催化行为。结果表明,NAC在裸碳糊电极（CPE）上的直接电化学氧化过程十分迟缓,而CFA/CPE对NAC的电化学氧化具有良好的催化作用。用循环伏安法（CV）、计时电流法（CA）测定了NAC在CFA/CPE上的电极过程动力学参数。电荷传递系数α=0.79,电催化氧化反应速率常数k=（4.40±0.10）×10^3（mol.L^-1）^-1.s^-1。用微分脉冲伏安法（DPV）测得催化氧化峰电流与NAC浓度在1.0×10^-6～7.5×10^-4mol.L^-1范围内呈良好的线性关系,线性回归方程为Ipa（μA）=4.075c（mmol.L^-1）＋2.671,r=0.9988,检出限为1.7×10^-7mol.L^-1。用该方法对市售药品富露施中的NAC含量进行测定,结果令人满意。     

Electrochemical Determination of Tyrosine in the Presence of Dopamine and Uric Acid at the Surface of Gold Nanoparticles Modified Carbon Paste Electrode

A gold nanoparticles modified carbon paste electrode (GN‐CPE) was used as a highly sensitive electrochemical sensor for determination of tyrosine (Tyr), dopamine (DA) and uric acid (UA) in phosphate buffer solution (PBS). The study and measurements were carried out by using cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamperometry methods. In DPV, the GN‐CPE could separate the oxidation peak potentials of DA and UA present in the same solution, though at the unmodified CPE the peak potentials were indistinguishable. The prepared electrode showed voltammetric responses with high sensitivity and selectivity for Tyr, DA and UA in optimal conditions, which makes it very suitable for simultaneous determination of these compounds. The calibration curves for Try, DA and UA were linear for the concentrations of each species. The proposed voltammetric approach was also applied to the determination of Tyr concentration in human serum as a real sample.     

分子氧在金属配合物担载磷铝分子筛修饰玻碳电极上的电催化还原反应

采用循环伏安法研究了负载金属配合物MnSALEN(SALEN=N,N-双水杨醛缩乙二胺)的磷铝分子筛APO-5复合催化剂修饰玻碳电极在水溶液中对分子氧的还原反应的电催化行为.结果表明,氧气的还原峰电位随扫描速率的增大负移,Ep~lnv呈线性关系;其还原峰电流随扫描速率的增大而增强,ip~v1/2呈直线关系.这说明分子氧在修饰电极PS/MnSALEN/APO-5/GCE上的还原是扩散控制的.根据Ep~lnv和ip~v1/2的线性关系计算出中性电解质溶液中分子氧在此修饰电极上的还原反应的电子转移数n接近4.即氧气在此修饰电极上被还原为水.     

Electrochemical Behavior of o‐Nitrophenol at Hexagonal Mesoporous Silica Modified Carbon Paste Electrodes

A hexagonal mesoporous silica (HMS) modified carbon paste electrode (CPE) was fabricated and characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) methods (ferrocene as a probe). The electrochemical behavior of nitrophenol (o‐NP) at the HMS modified electrode (HMSCPE) was investigated. Compared with CPE, a well‐defined reduction peak and a remarkably peak current response was observed. It is indicated that mesoporous HMS exhibited remarkable enhancement effects on the electrochemical reduction of o‐NP. The electrochemical reduction mechanism was also discussed. Consequently, a simple and sensitive electrochemical method was proposed for the determination of o‐NP, which was used to determine o‐NP in waste water samples.     

谷胱甘肽在nano-TiO2-咖啡酸复合修饰碳糊电极上的电催化氧化及电分析方法

研究了还原型谷胱甘肽( CSH)在nano-TiO2 -咖啡酸(CFA)复合修饰碳糊电极(nano-TiO2 - CFA/CPE)上的电催化氧化行为,并进行了测定.结果表明,GSH在CPE和nano-TiO2/CPE上的直接电化学氧化过程十分迟缓,nano-TiO2 - CFA/CPE比CFA/CPE对GSH的电化学氧...     

石墨烯修饰玻碳电极对多巴胺的电催化氧化

通过3-巯丙基三乙氧基硅烷(METMS)将氧化石墨烯(GO)固载到玻碳电极(GCE)表面, 用电化学方法还原GO制备石墨烯修饰玻碳电极(rGO-METMS-GCE). 利用傅里叶变换红外光谱(FTIR)、 拉曼光谱(Raman)、 扫描电子显微镜(SEM)和原子力显微镜(AFM)等技术对GO和rGO-METMS-GCE的结构和表面形貌进行表征. 采用循环伏安(CV)和差分脉冲溶出伏安(DPV)法研究了rGO-METMS-GCE对多巴胺(DA)的电催化氧化性能及反应机理. 结果表明, 与裸GCE相比, DA在rGO-METMS-GCE电极上的氧化还原峰电流(i_pa和i_pc) 增大4倍, 氧化峰电位负移106 mV, 氧化峰与还原峰电位差(ΔE_p)从202 mV降低至66 mV, DA电化学氧化可逆性明显改善, 表明rGO-METMS-GCE对DA电化学氧化具有显著电催化作用. DA在rGO-METMS-GCE上的反应机理为单电子转移过程.     

镍纳米粒子修饰碳糊电极直接电催化鸟嘌呤的研究

将镍纳米粒子与石蜡、石墨按照一定比例混合制备镍纳米粒子修饰碳糊电极,采用循环伏安法(CV)对修饰碳糊电极进行电化学表征,在0.1 mol/L B-R缓冲溶液(pH4.5)中研究了鸟嘌呤在该修饰电极上的电化学行为。结果表明,与裸碳糊电极相比,以掺杂法制备的镍纳米粒子修饰电极能够明显降低鸟嘌呤的过电位,增大其氧化电流,很好地催化氧化鸟嘌呤。在优化的实验条件下,鸟嘌呤在该修饰电极上的氧化峰电流与其浓度在1.0×10-5~5.0×10-4mol/L范围内呈良好的线性关系,检出限(3σ)为7.5×10-6mol/L。     

Electrochemical Determination of Dopamine Using a Novel Perylenediimide-Derivative Modified Carbon Paste Electrode

A novel perylenediimide derivative, N,N′-bis(4-{2-[2-(2-methoxyethoxy ethoxy]ethoxy}phenyl)-3,4:9,10-perylene tetracarboxydiimide, was utilized for the modification of a carbon paste electrode to develop a practical and sensitive electrochemical sensor for dopamine detection. The effects of experimental parameters (modifier amount, pH, and scan rate) on the dopamine peak current were examined. The performance of the modified carbon paste electrode was evaluated under optimum conditions and 4.6-fold increase in the peak current was obtained compared to an unmodified carbon paste electrode. The linear range was between 1 and 100?µM dopamine and the limits of detection and quantification were 0.011 and 0.036?µM, respectively. The developed sensor was also applied for the quantitative determination of dopamine in injections and promising results were obtained.     

Electrochemical Study of 4-Nitrophenol at a Modified Carbon Paste Electrode

 A zeolite-modified carbon paste electrode (CPE) has been used for the determination of 4-nitrophenol by differential pulse voltammetry (DPV). The electrochemical reduction of 4-nitrophenol at −1.0 V is carried out in a Britton-Robinson medium at pH 3.5. The cyclic voltammetric (CV) behaviour has been investigated to study the nature of the process. Studies on the effect of pH were carried out over the pH range 2–9 with the Britton-Robinson buffer solution, and the influence of pH on peak height and peak potential was analyzed. A linear relationship between peak intensity and concentration is obtained in the range 0.2–10 mg L⁻¹, with a detection limit of 0.04 mg L⁻¹; a relative standard deviation of 1.5% for a 5 mg L⁻¹ 4-nitrophenol concentration and a relative error of 2.6% were also obtained (n=11). Received March 3, 1998. Revision December 10, 1998.