环糊精葡萄糖基转移酶的固定化及其应用：Ⅲ.固定化环糊精葡萄糖基转…

用固定化环糊精葡萄糖基转移酶催化淀粉环化反应，考察了反应时间，乙醇浓度和淀粉液化程度对环糊精产率的影响。环糊精产率最高达５４％，固定化酶经多次重复使用或长时间连连续操作，酶活力降低较少。     

环糊精葡萄糖基转移酶的固定化及其应用──Ⅲ．固定化环糊精葡萄糖基转移酶制备环糊精的研究

用固定化环糊精葡萄糖基转移酶催化淀粉环化反应,考察了反应时间、乙醇浓度和淀粉液化程度对环糊精产率的影响。环糊精产率最高达54%,固定化酶经多次重复使用或长时间连续操作,酶活力降低较少,产品经纸色谱分离后用碘显色,发现产品主要为β-环糊精。     

环糊精葡萄糖基转移酶的固定化及其应用研究．Ⅱ．壳素糖作载体固定化环糊精葡萄糖基转移酶的研究

使用经戊二醛处理过的壳素糖作载体固定化环糊精葡萄糖基转移酶，研究了给酶量、吸附时间等对固定化效果的影响。考察了固定化后酶学性质的变化。实验表明，酶经固定化后，热稳定性提高，最适ｐＨ值向前移１个单位。１０ｍｍｏｌ／Ｌ的ＣａＣｌ２可以使酶活力有较大提高。     

基于固定化酶的流动荧光法测定血清中的葡萄糖

本文将固定化酶柱，光纤以及停流技术结合起来，研究了以廉价而易得的硫胺素为荧光底物的葡萄糖的荧光分析，提出了一种快速、简便、精确地测定葡萄糖的新方法。其线性范围为１．０￣６０．０ｍｇ／Ｌ，线性相关系数为０．９９９，检测限为０．１５ｍｇ／Ｌ。以５．０ｍｇ／Ｌ的葡萄糖作精度试验，ＲＳＤ％＝２．１％（ｎ＝１１）。该方法已成功地用于血清中葡萄糖的测定，结果与光度法相符。     

用金属离子处理多孔Al2O3载体对葡萄糖异构酶固载化的影响

1.前言 葡萄糖异构酶可以催化D-葡萄糖转化为D-果糖的反应。近年来,酶和细胞固定化技术得到迅速发展。用固定化葡萄糖异构酶生产果葡糖浆是目前世界上将固定化酶大规模用于工业生产最有成效的范例。对于异构酶的固定化,文献业已发表上百种的方法,但是工业上实际采用的只有戊二醛交联法、载体吸附法、包埋法以及细胞凝聚法等七、八种,其中以多孔无机载体吸附法制备的固定化葡萄糖异构酶生产能力最高。     

漆树酶固定化及其性质研究

本文介绍了用过渡金属水合氧化物固定化漆树漆酶的方法。考察了整合法固定漆树酶的最适条件。对固定化前后漆酶的性质进行了比较,并分析了造成固定化酶与游离酶性质差异的原因。     

高效液相色谱法分析葡萄糖异构酶在变性剂中的构象变化与活性的关系

建立了监测葡萄糖异构酶在不同浓度变性剂中构象变化过程的高效液相色谱法。葡萄糖异构酶在天然条件下,以四聚体形式存在,在不同变性剂的不同浓度下,会解聚成二聚体或单体,或整体结构变松散,而且葡萄糖异构酶的活性随着构象的变化也会有相应的变化。     

固定化酶法测定血清中葡萄糖和胆固醇

本文讨论了一种灵敏、高选择性的方法分别测定葡萄糖和胆固醇,并介绍了成二醛固定化酶(葡萄糖氧化酶或胆固醇氧化酶)后产生的过氧化氢借助于鲁米诺-铁氰化钾发光反应由流动注射法测定。对血清中样品的前处理和反应试剂浓度的影响也分别作了研究。本法有良好的线性工作范围,连续进样100次仍能保持工作的稳定性,相对标准误差为3.8～5.2%。     

Amperometric Glucose Determination by Means of Glucose Oxidase Immobilized on a Cellulose Acetate Film: Dependence on the Immobilization Procedures

Glucose microelectrodes were prepared by immobilizing glucose oxidase onto a cellulose acetate film coating a platinum wire. Hexamethylenediamine (HMDA) and Glutaraldehyde (GA) were employed as spacer and coupling agent, respectively. Sensitivities and linear response ranges were studied as a function of the relative amounts of HMDA and GA. The best sensitivity was found when HMDA and GA were 5% and 2.5% in aqueous solutions, respectively. Taking as a reference the functioning of this biosensor, the roles of HMDA and GA percentages appear to be opposed when the extension of the linear response range is considered. Indeed, an increase of one unit in HMDA percentage (from 5 to 6 %) induces an increase in the extension of the linear response range equal to that obtained with a decrease of one unit of GA percentage (from 2.5 to 1.5%).     

Immobilization of glucose isomerase and its application in continuous production of high fructose syrup

Bilayer glucose isomerase was immobilized in porousp-trimethylamine-polystyrene (TMPS) beads, through a molecular deposition technique. Some of the factors that influence the activity of immobilized glucose isomerase were optimized, with the enzyme concentration of 308 IU/mL, enzyme:matrix ratio of 924 IU/g wet carrier, and hexamethylenebis(trimethylammonium iodine) concentration of 15 mg/mL, giving the maximum catalytic activity (2238 IU/g dry gel) of the immobilized bilayer glucose isomerase, retaining 68.5% of the initially added activity. The half-life of the immobilized bilayer glucose isomerase was approx 45 d at pH 8.5, 60°C, with 50% (w/v) glucose as substrate. The specific productivity of the immobilized bilayer glucose isomerase was 223 g dry D-glucose/g dry immobilized enzyme per day.     

Immobilization of glucose isomerase and its application in continuous production of high fructose syrup

Bilayer glucose isomerase was immobilized in porousp-trimethylaminepolystyrene (TMPS) beads through a molecular deposition technique. Some of the factors that influence the activity of immobilized glucose isomerase were optimized, with the enzyme concentration of 308 IU/mL, enzyme-to-matrix ratio of 924 IU/g wet carrier, and hexamethylene bis(trimethylammonium iodine) concentration of 15 mg/mL giving the maximum catalytic activity (2238 IU/g dry gel) of the immobilized bilayer glucose isomerase, retaining 68.5% of the initially added activity. The half-life of the immobilized bilayer glucose isomerase was approx 45 d at pH 8.5, 60°C, with 50% (w/v) glucose as substrate. The specific productivity of the immobilized bilayer glucose isomerase was 223 g dry D-glucose/g dry immobilized enzyme per d.     

Immobilization of Glucose Oxidase and 2-Hydroxybiphenyl 3-Monooxygenase in Mesoporous Silica: Characterization Studies and Construction of an Amperometric Glucose Biosensor

Immobilization techniques that preserve the activity of biomolecules have many potential applications. Mesoporous silica has been used to encapsulate a wide variety of biomolecules. In this particular work, MCM-41 silica has been used as a matrix for the immobilization of two important enzymes, HpbA and GOx. The enzyme 2-hydroxybiphenyl 3-monooxygenase (HpbA) is involved in the microbial degradation of 2-hydroxy and 2,2′-dihydroxybiphenyl, which occurs during the desulfurization of coal and petroleum, while Glucose oxidase (GOx) catalyzes the oxidation of β-D-glucose to δ-gluconolactone. The silica-enzyme hybrids were extensively characterized and the one with GOx was used for the construction of a biosensor.     

A Glucose Biosensor Based on Immobilization of Glucose Oxidase on Platinum Nanoparticle Doped Santa Barbara Amorphous Material-15

A novel electrochemical glucose biosensor was prepared by combining platinum nanoparticle doped Santa Barbara Amorphous Material 15 with glucose oxidase. The resulting material demonstrated high stability and reactivity for catalyzing glucose electrolytic oxidation, primarily due to the high surface area of these catalysts. This glucose biosensor was capable of interference-free determination of glucose with a linear dynamic range from 0.03 to 12.0 mmol L^?1. In addition, it has the advantages of simple preparation and good stability. The reported method is promising for the determination of glucose in human serum.     

聚苯胺葡萄糖氧化酶电极的催化过程

用电化学方法固定在直径为0.5mm铂丝上的聚苯胺(PANI)葡萄糖(GOD)电极对葡萄糖有催化氧化作用.在0～-0.6V(vs.SCE)的电极范围内,在电极的循环伏安曲线上观察到与葡萄糖浓度有关的氧的还原峰和GOD还原态的氧化峰,用此GOD还原态的氧化峰电流可定量检测葡萄糖的浓度。本文提出在PANI电极上存在着酶反应氧化还原电荷直接传递的可能性。     

蜘蛛丝素和聚乙烯醇固定葡萄糖氧化酶 制备葡萄糖传感器

用蜘蛛丝素和聚乙烯醇的混合材料把葡萄糖氧化酶固定在氧电极表面,制成葡萄糖氧化酶电极。传感器对葡萄糖有灵敏的响应,平均响应时间为20s,电位变化值与葡萄糖浓度在3.0×10     

Immobilization of invertase and glucose oxidase in poly 2-methylbutyl-2-(3-thienyl) acetate/polypyrrole matrices

Immobilization of invertase and glucose oxidase in conducting polypyrrole and copolymers of poly 2-methylbutyl-2-(3-thienyl) acetate with pyrrole were achieved via electrochemical method. Sodium dodecyl sulphate was found to be the most suitable supporting electrolyte. Maximum reaction rate, Michaelis-Menten constant and optimum temperatures were determined for native and immobilized enzymes. Storage and operational stabilities of enzyme electrodes were also investigated.     

木瓜蛋白酶的固定化研究

木瓜蛋白酶具有广谱的蛋白水解酶活性,广泛地应用于啤酒、饮料的澄清,肉类嫩化和复配消化药物等方面。近年来,为了扩大该酶在啤洒澄清上的应用,一些研究者致力于探索该酶的固定化研究,以提高该酶的利用效率,降低生产成本。     

葡萄糖氧化酶在炭黑上的固定及直接电化学

经红外光谱和电化学测量证明, 用简单的吸附法能将葡萄糖氧化酶(GOx)固定在炭黑(CB)表面. 电化学测量表明, 固定在CB上的GOx能进行准可逆的直接电化学反应, 其式量电位(E0’)为-0.436 V, 在40-150 mV·s-1范围内, 不随扫描速率而变化. 电化学反应速率常数(ks)为0.800 s-1, 比文献报道的大30多倍. 而且, 固定在CB上的GOx能保持其对葡萄糖氧化的生物电催化活性. 即使在保存两周后, 其电催化活性仅下降了5%, 表明固定在CB上的GOx有良好的稳定性.