ENZYME ELECTRODES BASED ON CHITOSAN SCAFFOLDINGS

基于壳聚糖支架的酶电极

• 批准号: 6346173
• 负责人: WALDEMAR GORSKI
• 金额: $ 14.87万
• 依托单位: UNIVERSITY OF TEXAS SAN ANTONIO
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-08-01 至 2001-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6346173
• 关键词: X ray; amine oxidase (copper); aminoacid oxidase; biomaterial compatibility; biomaterial development /preparation; biomaterial evaluation; biosensor device; colorimetry; electrochemistry; electron transport; enzyme activity; enzyme electrodes; glucose oxidase; immobilized enzymes; infrared spectrometry; interferometry; membrane fusion; molecular film; osmium; polymers; ruthenium; scanning electron microscopy; ultraviolet spectrometry

Studies are proposed for the development of a bio-compatible approach to integration of enzymes of enzymes and electrodes by using scaffoldings of a polysaccharide biopolymer, chitosan. Such enzyme electrodes are projected to have better operational stability, insufficient biocompatibility with enzymes and limited selectivity. Chitosan has been selected because of an unusual combination of its properties which include excellent membrane forming ability, good adhesion, biocompatibility, and susceptibility to chemical modifications due to the presence of reactive hydroxyl and amino function groups. In order to take advantage of these properties, enzymes will be incorporated into thin films of chitosan cast on electrode surfaces. The work is reliant on covalent attachment of enzymes to chitosan chains by using bifunctional cross-linkers. The amino and hydroxyl groups of chitosan will also be used for attachment of redox mediators as well as permeability controlling agents in order to introduce an extra level of molecular recognition. Such hybrid materials will provide the basis for a new line of stable biosensors in which the selectivity of the enzymatic reaction will not be compromised by the signal transduction process. In the second part of the project, the protective matrix of chitosan will be combined with solid electrocatalysts based on transition metal complexes. Preliminary studies showed that such redox crystals, when assembled together with glucose oxidation in chitosan films, promote anaerobic reoxidation of the enzyme at a very low driving force. This phenomenon may represent a new mode of electron transfer that may be relevant for future biosensor development. For proof-of-concept purposes, several oxidase enzymes (glucose oxidase, L-glutamate oxidase, L-AND D-AMINO acid oxidase, L-lactate oxidase, diamine oxidase), and redox mediators (Ru and Os complexes) will be immobilized within the host matrix of chitosan deposited on the electrode surfaces. Electrochemical and spectroscopic techniques will be used to probe for the composition-stability reactivity patterns in such integrated biosensing layers. The proposed materials will be appropriate not only for sensor applications, but also for basic studies of the transfer reactions and ability to manipulate them will lead to further developments, not only in the biosensor field but also in bioelectronics. Central to this is our ability to interface the biological system and electrode in a stable fashion. This fundamental question stimulated the present proposal.

研究提出了一种生物相容性的方法，通过使用支架的多糖生物聚合物，壳聚糖的酶和电极的酶的整合的发展。这种酶电极预计具有更好的操作稳定性、与酶的生物相容性不足和有限的选择性。壳聚糖已被选中 这是因为它具有不寻常的性能组合，包括优异的成膜能力、良好的粘附性、生物相容性和由于存在反应性羟基和氨基官能团而对化学改性的敏感性。为了利用这些特性，将酶掺入到在电极表面上浇铸的壳聚糖薄膜中。这项工作依赖于通过使用双功能交联剂将酶共价连接到壳聚糖链上。壳聚糖的氨基和羟基也将用于附着氧化还原介体以及渗透性控制剂，以引入额外水平的分子识别。这种杂化材料将为一种新的稳定的生物传感器提供基础，其中酶反应的选择性不会受到信号转导过程的影响。在该项目的第二部分中，壳聚糖的保护基质将与基于过渡金属络合物的固体电催化剂相结合。初步研究表明，这种氧化还原晶体，当组装在一起与葡萄糖氧化壳聚糖膜，促进厌氧再氧化的酶在一个非常低的驱动力。这种现象可能代表了一种新的电子转移模式，可能与未来的生物传感器发展有关。出于概念验证的目的，将几种氧化酶（葡萄糖氧化酶、L-谷氨酸氧化酶、L-和D-氨基酸氧化酶、L-乳酸氧化酶、二胺氧化酶）和氧化还原介体（Ru和Os络合物）固定在沉积在电极表面上的壳聚糖的主体基质内。电化学和光谱技术将用于探测这种集成生物传感层的组成稳定性反应模式。所提出的材料不仅适用于传感器应用，而且适用于转移反应的基础研究，并且操纵它们的能力将导致进一步的发展，不仅在生物传感器领域，而且在生物电子学领域。其核心是我们能够以稳定的方式连接生物系统和电极。这一根本问题促成了目前的建议。