基于Nafion-二茂铁膜修饰膜的H2O2生物传感器

该文通过Nafion、戊二醛和牛血清蛋白的交联,将电子传导体二茂铁和辣根过氧化物酶固定在玻碳电极上,制成了一种过氧化氢生物传感器.这种新型过氧化氢生物传感器性能稳定、灵敏度高,过氧化氢在1.0×10-4～8.0×10-3mol/L的浓度范围内与传感器的电流强度呈线性关系.     

丙烯腈-丙烯酸共聚物多孔膜的硫化物传感器

采用自由基聚合方法在金电极表面合成丙烯腈-丙烯酸的共聚物多孔膜并用作固定酶的载体.再通过戊二醛将辣根过氧化物酶交联固定在丙烯腈-丙烯酸的共聚物多孔膜上制得过氧化氢生物传感器.硫化物抑制酶的活性使还原电流减小,根据电流域小的程度实现了对硫化物的测定.丙烯腈-丙烯酸共聚物多孔膜具有大的表面积和高的吸附能力.有利于改进传感器的检测下限.实验结果表明:将辣根过氧化物酶固定在丙烯腈-丙烯酸的共聚物多孔膜金电极上,作为一种检测硫化物的抑制型传感器,分析响应性能良好.     

固定酶的新型基质膜-羊肠衣膜的结构、固定方法及其效果的研究

<正> 电极型生物传感器多是将敏感物质即生物活性物质,如,酶固定在基质膜(载休)上,基质膜采用的是高分子材料,其物理性质对敏感物质的活性和测定结果有影响,国外已有专门报告。前述的高分子材料应能制成薄膜并具多孔     

LOD酶电极的临床应用研究

研制一种测定乳酸的生物传感器.乳酸氧化酶(LOD)通过共价键固定在尼龙网上制备乳酸氧化酶膜,制得的酶膜固定在流动注入式氧电极上构成流动注入式LOD酶电极.在酶膜上覆盖透析膜限制乳酸扩散,改善传感器响应的线性范围,以符合临床血乳酸检测要求.该传感器对血样测试的结果与常规酶(LDH)光学测定法比较,经统计学分析,两者无差异.结果显示,该LOD酶电极用于临床血乳酸的检测具有可行性.     

用光学传感膜R-302测定碘化物

作者在用光学传感膜芘丁酸测定碘离子的研究基础上,改用罗丹明123(Rhodmine123)作分子探针,辅以精选的固态支持剂和增塑剂,制成了对碘离子敏感的,基于荧光猝灭原理的可逆性光学传感膜(简称R—302膜).用它制成实用的用于碘离子测定的光纤化学传感器,得到较满意的结果.1 实验部分1.1 仪器和试剂     

双分子层脂质膜的特性及其应用

双分子层脂质膜 (BLM )具有生物细胞膜的生物兼容性 ,是固定生物活性物质的理想材料 ,因此其在生物医学研究和生物传感器的研制领域具有广泛的应用前景。介绍了BLM的特性及其修饰 ,评述了双分子层脂质膜系统在生物医学应用和生物传感器开发方面的最新进展 ,展望了双分子层脂质膜系统应用的发展趋势。     

辣根过氧化物酶标间苯二胺膜电极的研制

目前,用作传感器的功能膜材料不多,见诸文献的有:测定梅毒抗体的醋酸乙烯膜,测定二硝基酚(DNP)的聚氯乙烯膜,测定人体免疫球蛋白IgG的聚苯乙烯活性膜等。本文采用电化学聚合方法形成间苯二胺膜,并探讨了电化学聚合、活化、偶联制备辣根过氧化物酶标膜电极的实验条件及其性能。实验证明:聚合膜具有较多的供生物材料偶联的氨基,制成的膜极薄,在电极表面结合牢固,具有抗碱及非氧化性酸腐蚀的性     

聚乙烯缩丁醛膜固定聚亚甲基蓝和纳米银修饰的葡萄糖生物传感器

用循环伏安法在玻碳电极上电聚合一层稳定的亚甲蓝聚合物膜,研究了这层膜在0.1 mol/L磷酸缓冲溶液(pH 7.0)中的电化学性质.用纳米银颗粒吸附葡萄糖氧化酶(GOD),采用乙烯醇缩丁醛(PVB)为辅助固酶基质将其固定于亚甲蓝修饰的玻碳电极表面,制成了新型葡萄糖生物传感器.实验发现,加入纳米银后提高了酶电极对葡萄糖的电流响应,所制备的传感器具有响应快、灵敏度高、稳定性好,对葡萄糖的线性响应范围为2.5×10-6～2×10-3mol/L,检测下限为1×10-6 mol/L,并具有抗坏血酸、抗尿酸干扰的特点.     

基于氧传感膜荧光特性的溶解氧传感器研制

基于氧传感膜荧光特性研制了一种低成本、小型化的溶解氧传感器.对传统氧传感膜的制备方案进行了优化,结合其透光特性对所制备的传感膜优劣进行甄别和选优.在此基础上,重点研究了水温、浸泡时间等因素对传感膜荧光发射强度的影响.为提高溶解氧的测量精度,设计了一种45°角斜面传感器探头结构,有效降低了水中气泡对溶解氧的测量干扰.实验结果表明:该溶解氧传感器能够准确测量0 ～20 mg/L范围内的待测液体的含氧量,检测误差为±2％,检测精度达±0.1 mg/L,在工农业生产、水质监测及水产养殖等方面具有较好的应用前景.     

胱胺自组装膜压电免疫传感器用于抗胰蛋白酶的测定

该文研制成一种基于胱胺自组装测定抗胰蛋白酶的压电免疫传感器.应用胱胺在石英晶体表面自组装一带有氨基的自组装膜,通过戊二醛交联,成功地固定抗胰蛋白酶抗血清,并用于抗胰蛋白酶的测定.详细考察了胱胺自组装情况,抗体包被和免疫反应的主要实验条件以及传感器的响应性能.在优化的实验条件下,传感器响应的线性范围0.23～23.9μg/mL,回归方程Y=44.25+12.47X,相关系数r=0.9933.     

Gold nanoparticles-coated eggshell membrane with immobilized glucose oxidase for fabrication of glucose biosensor

This work reports the fabrication and application of a glucose biosensor based on the catalytic effect of gold nanoparticles (AuNPs) on enzymatic reaction for blood glucose determination. AuNPs were initially in situ synthesized on the surface of an eggshell membrane (ESM) which was subsequently immobilized with glucose oxidase (GO_x) to produce a GO_x-AuNPs/ESM. The GO_x-AuNPs/ESM was positioned on the surface of an oxygen electrode to form a GO_x-AuNPs/ESM glucose biosensor. The effects of pH, concentration of phosphate buffer solution and amount of GO_x on the response of the GO_x-AuNPs/ESM glucose biosensor were studied in detail. AuNPs on GO_x/ESM can improve the calibration sensitivity (30% higher than GO_x/ESM without AuNPs), stability (87.3% of its initial response to glucose after 10-week storage) and shortens the response time (<30 s) of the glucose biosensor. The linear working range for the GO_x-AuNPs/ESM glucose biosensor is 8.33 μM to 0.966 mM glucose with a detection limit of 3.50 μM (S/N = 3). The biosensor has been successfully applied to determine the glucose in human blood serum samples and the results compared well to a standard spectrophotometric method commonly used in hospitals. Our work demonstrates that the developed GO_x-AuNPs/ESM glucose biosensor has potential in biomedical analysis.     

An ISFET glucose sensor with a silicone rubber membrane for undiluted serum monitoring

An ion-sensitive field-effect transistor (ISFET) glucose sensor with a silicone rubber membrane has been fabricated and its operation has been demonstrated in monitoring glucose concentration in serum and suction effusion fluid without dilution. The sensor characteristics are evaluated by measuring glucose concentrations in HEPES—NaOH buffers with different buffer capacities. The silicone membrane, which restricts glucose diffusion, expands the linear calibration range up to 500 mg/dl glucose. This membrane also restricts buffer species diffusion, so that the sensor output is not affected by solution buffer capacity. Moreover, investigation on the relationship between the sensor response and dissolved oxygen concentration shows that this sensor maintains constant outputs in solutions containing 1.5–7.5 ppm of oxygen. The sensor is mounted in a flow cell, into which serum samples and HEPES—NaOH buffer solution are alternately fed by a peristaltic pump. It takes 15 min to measure one sample. In 21 measurements on the same serum sample, the sensor output variance coefficient is found to be 4.7%. The sensor is applied to monitor glucose concentration in glucose-loaded rabbit suction effusion fluid. The glucose-level profile obtained by this sensor shows a good correlation with that measured by a conventional glucose analyser.     

用于血糖无创检测的葡萄糖传感器研究

研制一种新型葡萄糖传感器,初步实现用于反离子电渗透技术提取皮下组织液的葡萄糖的浓度测量。用铁氰化钾作为电子媒介体,固定在聚环氧乙烷凝胶里的葡萄糖氧化酶与溶液中的葡萄糖催化氧化生成葡萄糖酸和亚铁氰化钾,通过检测该反应产生的氧化还原电流的大小来计算葡萄糖溶液的浓度。新型葡萄糖传感器的检测浓度范围2～22 mmol/L内线性度较好,传感器的一致性测试表明:同一传感器多次测量的偏差不超过2%,反应时间较短,接近于1 s。     

基于葡萄糖氧化酶-空壳钯修饰的新型葡萄糖传感器

制备了空壳钯纳米粒子,通过TEM对其空壳结构进行了表征。将空壳钯纳米粒子和葡萄糖氧化酶（GOD）修饰在玻碳电极（GC）表面,构建了新型的葡萄糖传感器。空壳钯纳米粒子对过氧化氢（H202）具有良好的催化还原作用,通过检测酶反应产生的H202可检测葡萄糖的浓度。在-0．3V工作电位下,在2．5×10＾－5mol／L到2．7...     

基于碳纳米管固定葡萄糖氧化酶的ECL葡萄糖传感器的制备

将葡萄糖氧化酶(GOD)固定在多壁碳纳米管(MWCNTs)修饰电极(ME)上,GOD催化氧化葡萄糖生成过氧化氢,并使鲁米诺产生电致化学发光(ECL),据此构建了一种新型ECL葡萄糖传感器.结果表明:CNTs修饰的电极对鲁米诺和H2O2反应具有显著的电催化活性和增敏效果.该传感器对葡萄糖检测的线性范围为0.01～10.0...     

基于双酶固定化技术的微透析葡萄糖传感器

建立了一个双酶葡萄糖传感器微透析系统,并且在体外实验中考察了影响系统响应结果的关键因素,即固定化酶膜技术和微透析系统的灌注速率。优化的系统采用夹心法固定化葡萄糖氧化酶和过氧化氢酶于金叉指电极,并采用20μl/min的灌注速率。系统具有良好的线性、灵敏度和响应时间。     

Bioelectrochemical sensor based on PQQ-dependent glucose dehydrogenase

Bioelectrochemical responses of pyrroloquinoline quinone (PQQ) dependent glucose dehydrogenase (PQQ-GDH) have been studied with the use of two principal electrode configurations: (i) glassy carbon electrode, coated with Nafion layer, containing sorbed N-methylphenazonium (NMP), and overcoated by an enzyme layer, crosslinked by glutaraldehyde, and (ii) glassy carbon electrode, containing an electropolymerized layer of either Toluidine blue, or o-phenylenediamine, or pyrrole, and overcoated by a crosslinked enzyme layer. When operated within the potential window of 0.0–0.3 V, Nafion-coated and NMP-soaked bioelectrode shows an anodic current response to glucose without the presence of electron transfer mediator in solution. The current–concentration profile obtained resemble to that, typical for enzyme catalyzed reaction. Other configurations studied showed bioelectrochemical response to glucose only in the presence of soluble mediator NMP. Without any mediator, no electrochemical responses have been registered. It indicates that direct electron transfer between PQQ-GDH and all types of electrodes modified during current work is undetectable.     

Ultra-sensitive polysilicon wire glucose sensor using a 3-aminopropyltriethoxysilane and polydimethylsiloxane-treated hydrophobic fumed silica nanoparticle mixture as the sensing membrane

In this paper a highly sensitive glucose biosensor is proposed based on a polysilicon (poly-Si) wire structure coated with 3-aminopropyltriethoxysilane (γ-APTES) mixed with polydimethylsiloxane-treated hydrophobic fumed silica nanoparticles (NPs) as the sensing membrane. The γ-APTES and fumed silica NPs mixture was directly transferred to and coated onto the poly-Si wire region with the help of a focus-ion-beam (FIB) processed capillary atomic-force-microscope (C-AFM) tip. After the necessary curing and UV illumination processes, the resultant sensor showed an extremely wide linear detection range from 0.1 μM to 10 mM with a channel current sensitivity as high as 5.33 A mM⁻¹ cm⁻² (or a channel conductance sensitivity of 70 μS mM⁻¹), and a detection limit as low as 10 nM can be achieved. Our experimental results showed that the poly-Si wire sensor has good selective analysis and operational stability on glucose detection under a 10:1 concentration ratio of glucose and uric acid. Its linear range and lowest detection limit remain virtually unimpaired in the presence of uric acid.     

葡萄糖传感器保存稳定性的研究

利用丝网印刷方法,在碳电极上吸附固定氧化酶制备葡萄糖传感器。探讨了氧化酶固定化过程中氧化酶含量、铁氰化钾含量、缓冲液类型以及干燥过程对传感器保存稳定性的影响。结果发现,当氧化酶的质量分数为4%,铁氰化钾的质量分数为4%,邻苯二甲酸氢钾(pH=6)作为缓冲液,采用超干燥技术,在相对湿度为10%的空气中干燥传感器,制得传感器的表观米氏常数为6.06mmol/L,其保存6个月后的响应电流曲线与刚制作完成的传感器响应电流曲线基本符合。