共查询到19条相似文献,搜索用时 62 毫秒
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利用溶胶-凝胶生物传感器测定饱和苯系物废水中酚类化合物 总被引:3,自引:0,他引:3
研制了用溶胶-凝胶包埋酪氨酸酶碳糊生物电极。其生物电极的工作条件为:电位为-100mV(vs.SCE),溶液pH5.40,响应时间为3min。本文方法对苯酚的检出限为1.00×10-6mol/L,线性范围为1.00×10-6~1.00×10-4mol/L,相对标准偏差为1.04%。实验结果表明,本电极对邻甲酚、对苯二酚、邻苯二酚、对氯苯酚都有良好的响应,但对邻氨基酚、间苯二酚、对甲苯酚、邻硝基酚、2.4二甲基酚响应较差。用本法对化工废水中酚类进行了测定,有机干扰物苯、甲苯、二甲苯对测定结果无影响。 相似文献
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基于溶胶-凝胶固定技术的生物组织传感器 总被引:4,自引:0,他引:4
报道了一个制备生物组织传感器的新技术。将溶胶 凝胶与植物液汁按一定比例结合 ,使天然植物中的多酚氧化酶被固定于溶胶 凝胶中 ,将其滴涂于预先涂有一层Nafion膜的铂盘电极表面 ,构成带有Nafion 溶胶凝胶 植物液汁的复合修饰膜的生物传感器 ,用于测定神经递质多巴胺。采用循环伏安法和线性扫描伏安法考察了传感器的电化学特性 ,比较了不同植物品种及其不同部位组织的生物催化活性 ;研究了乙醇用量、水酯比、植物液汁用量等因素的影响 ;考察了Nafion膜的防干扰性能。采用差示脉冲伏安法对多巴胺进行定量分析 ,线性范围为 2× 10 -6~ 1× 10 -4mol/L ;检出限为 8.0× 10 -7mol/L。与传统的组织电极相比 ,本传感器具有一系列特点。 相似文献
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基于功能化溶胶-凝胶膜的乳腺癌抗原免疫传感器 总被引:5,自引:0,他引:5
结合溶胶-凝胶(sol-gel)和交联技术,将乳腺癌抗体固定在铂盘电极表面的氨基化sol-gel功能膜上,制备出用于检测乳腺癌抗原(CA15-3)的免疫传感器.用红外光谱验证了该传感器功能膜的形成过程和组成结构,采用循环伏安法对传感器逐层修饰过程进行了表征,并对传感器功能膜的作用机理进行了探讨.该法检测CA15-3的线性范围为8~240U/mL,线性回归方程为ΔE=75.75lgc-56.36,r=0.998.结果表明,该方法很好地保持了被固定抗体的活性,增强了传感器的稳定性,所制备的传感器于4℃干态保存30d,其响应信号基本不变.且该传感器响应迅速、灵敏度高、选择性好,血清中常见抗原不干扰测定. 相似文献
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《Electroanalysis》2006,18(16):1572-1577
An amperometric tyrosinase biosensor was developed via a simple and effective immobilization method using the self‐assembled monolayers (SAMs) technique. The organic monolayer film was first formed by the spontaneous assembly of thiolor sulfur compound (1,6‐hexanedithiol, HDT) from solution onto gold electrode. When these thiol‐rich surfaces were exposed to Au colloid, the sulfurs form strong bonds to gold nanoparticles, anchoring the clusters to the electrode substrate. After the assembly of gold nanoparticles layer, a new nano‐Au surface was obtained. Thus, the tyrosinase could be immobilized onto the electrode. The tyrosinase retained its activity well in such an immobilization matrix. The various experimental variables for the enzyme electrode were optimized. The resulting biosensor can reach 95% of steady‐state current within 10 s, and the trend in the sensitivity of different phenolic compounds was as follows: catechol>phenol>p‐cresol. In addition, the apparent Michaelis–Menten constant (K and the stability of the enzyme electrode were estimated. 相似文献
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Tyrosinase/laccase bienzyme biosensor for amperometric determination of phenolic compounds 总被引:1,自引:0,他引:1
Jolanta Kochana Pawel Nowak Anna Jarosz-Wilkoazka Marta Biero 《Microchemical Journal》2008,89(2):171-174
Tyrosinase/laccase bienzyme biosensor for amperometric determination of phenolic compounds was constructed. Enzymes were immobilized in titania gel matrix. The obtained biosensor was successfully used for determination of 2,6-dimethoxyphenol, 4-tertbutylcatechol, 4-methylcatechol, 3-chlorophenol and catechol. The highest sensitivity and the widest linear range were noticed for catechol, 234 mA L mol− 1 and 2.0 × 10− 7–3.2 × 10− 5 mol/L, respectively. Detection limit for catechol, at signal-to-noise ratio of 3 was 1.3 × 10− 7 mol/L. 相似文献
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《Analytical letters》2012,45(12):1842-1853
A biosensor was fabricated by incorporating laccase in a ZnO sol-gel with chitosan as a matrix for the determination of catechol. The ZnO nanoparticles were characterized by X-ray diffraction and atomic force microscopy. The conductivity of the chitosan/ZnO/glassy carbon electrode film was investigated by alternating current impedance. The biosensor was employed to monitor the reduction of catechol, and the peak current increased linearly with concentration between 1.0 × 10?6 and 1.0 × 10?4 mole per liter with a limit of detection of 2.9 × 10?7 mole per liter. The laccase biosensor exhibited good stability, reproducibility, and some selectivity. 相似文献
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掺杂纳米普鲁士蓝溶胶-凝胶修饰葡萄糖生物传感器 总被引:4,自引:0,他引:4
采用溶胶-凝胶法制备了纳米普鲁士蓝微粒,将含纳米普鲁士蓝微粒的TiO2溶胶-凝胶固定在玻碳电极表面得到纳米普鲁士蓝修饰电极,该电极对H2O2产生灵敏的响应,线性范围为0.5~400μmoL/L,较常规普鲁士蓝修饰电极(线性范围为25~500μmol/L)灵敏。电极表面再用溶胶.凝胶法固定葡萄糖氧化酶后构建了葡萄糖生物传感器,响应范围0~20mmoL/L,葡萄糖氧化酶表观米氏常数为8.04mmoL/L。实验表明,该法适合于批量制作高灵敏和高重现性的生物传感器。 相似文献
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A study was been made of tyrosinase amperometric biosensors for the determination of organophosphorus (dichlorvos) and triazine (atrazine) pesticides. The biosensors are based on the competitive inhibition of tyrosinase (Tyr) by the pesticides. Tyr becomes active when the reduced form of the charge‐transfer mediator (1,2‐naphthoquinone‐4‐sulfonic acid (NQS), 1,2‐naphthoquinone (NQ) and 3,5‐di‐tert‐butyl‐1,2‐benzoquinone (t‐BQ) were tested) are electrochemically generated onto the working electrode surface, which permits modulation of the enzymatic activity. The inhibition is reversible as there is a complete recovery of the current due to enzyme activity without the studied pesticides. The charge‐transfer mediators (the quinonic molecules) and the enzyme were co‐immobilized on the working electrode to obtain reagentless biosensors. Kinetic studies in solution were carried out to compare the efficiency of the measurement mechanism. 相似文献
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以硼掺杂金刚石(boron-doped d iamond,BDD)薄膜作基底,利用光化学反应将含有碳碳双键的烯丙胺化合物修饰在BDD表面,形成氨基单分子层,再经过酰胺键的连接使酪氨酸酶固定在氨基化的金刚石表面,从而制得酪氨酸酶修饰的电极.应用循环伏安法研究该电极用于酚类化合物(包括苯酚、对甲基苯酚和对苯二酚等)检测的灵敏度、线性范围及其稳定性. 相似文献
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普鲁士蓝修饰电极结合硅溶胶-凝胶技术制备高灵敏葡萄糖传感器 总被引:9,自引:0,他引:9
基于普鲁士蓝修饰玻碳电极结合二氧化硅溶胶 凝胶固定化酶技术构造具有“三明治”式结构的酶电极。考察了酶电极对葡萄糖的电化学响应以及操作条件。结果表明 :所制备的传感器在pH 6 .5 ,电位为- 0 .0 5V条件下对葡萄糖在 0~ 5mmol/L呈线性响应 ,响应时间为 12s ,检出限为 0 .0 2mmol/L ,灵敏度高达1 182 μA/ (mmol·L-1)。传感器的稳定性好 ,4 5d其响应值仍保持 90 %。 相似文献
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纳米碳管修饰铂结合溶胶-凝胶固定酶制备高性能胆碱生物传感器 总被引:11,自引:3,他引:8
为了提高胆碱传感器的灵敏度和抗干扰性,以纳米碳管修饰铂电极为基础电极,采用溶胶-凝胶法固定胆碱氧化酶(ChOx),构建了电流型胆碱检测生物传感器,对纳米碳管修饰电极的电化学特征进行分析,得知纳米碳管的引入不仅使电极对H2O2的催化电流增大,同时降低了电催化所需的恒定电位。讨论了缓冲液介质、pH值、酶负载量对传感器响应的影响。研究表明,所制备的传感器在pH 7.2、电位为0.15V条件下对氯化胆碱的线性响应范围为5.0×10-6~1.0×10-4mol/L;检出限为5.0×10-7mol/L;灵敏度为9.48μA/mmol/L。传感器的稳定性好,经过1个月,仍可保持初始电流的85%。抗干扰能力有很大提高。用于人体血清中的胆碱浓度测定,结果令人满意。 相似文献
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Liyuan Chen Baoxiang Gu Guoping Zhu Yafeng Wu Songqin Liu Chunxiang Xu 《Journal of Electroanalytical Chemistry》2008,617(1):7-13
In this work, the adsorption of tyrosinase on ZnO nanorods and its electrocatalytic behaviors were investigated. The mushroom tyrosinase with low isoelectric point was expected to adhere on the positively charged surface of ZnO nanorods by electrostatic attraction in a neutral solution. Scanning electron microscope images and spectroscopic analysis demonstrated the adsorption of tyrosinase on ZnO nanorods and the adsorbed tyrosinase remain its bioactivity to a large extent. In the presence of tyrosinase, a roughly and cyathiform of nanosized ZnO films was obtained. This open, three-dimensioned ramiform structure made the move through and exchange the electron with GCE more easily, and thus accelerating the electron transfer between electroactive and GCE. The adsorbed tyrosinase could catalyze the oxidation of phenol and catechol. The linear concentration ranges were from 0.02 to 0.1 mM and 0.01 to 0.4 mM, for phenol and catechol, respectively. The apparent Michaelis-menten constant , a reflection of the enzymatic affinity, was 0.24 mM for phenol and 1.75 mM for catechol, which suggests a large affinity to phenolic compound. The proposed methods presented a way for further studies of the immobilization and electrochemistry of proteins on nanostructured materials. 相似文献