Electrodeposition Leading to Immobilized Enzyme Biosensor Electrodes

这个小企业创新研究（SBIR）第一阶段项目是在分析和表面化学的一般领域以及生物传感器的子领域。本实验活动的主旨是评估一种新的、基于电沉积的酶生物传感器电极生产方法。本研究的目的是在碳棒和其他廉价的导电材料上电沉积含有测试酶的胶体金，在保持酶的生物活性的同时提供方便的电子转移。研究任务包括：(1)通过两种方法（直接在表面吸附和通过间隔臂的共价附着）中的任意一种将测试酶固定在胶体金颗粒上；(2)用电沉积法从含有所附试验酶的胶体金制备电极；(3)测定固定化酶的活性；(4)将固定化测试酶的电子转移特性耦合到电活性金表面。这项研究的结果应该证明了电沉积作为一种可行的生产生物电极的方法的可行性。基于酶特异性的电化学传感器在医学诊断、环境监测和过程控制等方面具有广阔的应用前景。目前商用生物传感器设计的主要问题是不稳定、响应缓慢，以及酶和电极表面之间缺乏直接、有效的电耦合。第一阶段SBIR项目的成功完成可能会带来新的高效技术，用于生产具有理想特性的多分析物传感器。

This Small Business Innovation Research (SBIR) Phase I project is in the general area of analytical and surface chemistry and in the subfield of biosensors. The thrust of this experimental activity is to evaluate a new, electrodeposition-based method for the production of enzyme biosensor electrodes. The objective of this research is to electrodeposit colloidal gold containing a test enzyme on carbon rods, and other inexpensive conducting materials, in a manner that maintains biological activity of the enzyme while providing for facile electron transfer. The research tasks consist of (1) immobilization of the test enzyme on colloidal gold particles by each of two methods (adsorption directly on the surface and covalent attachment via a spacer arm); (2) production of electrodes from the colloidal gold containing the attached test enzyme by an electrodeposition method; (3) measuring the activity of the immobilized enzyme; and (4) coupling the electron transfer characteristics of the immobilized test enzyme to the electroactive gold surface. The results of this research should demonstrate the feasibility of electrodeposition as a viable method for the production of bioelectrodes. Electrochemical sensors based on enzyme specificity have broad potential in medical diagnostics, environmental monitoring, and process control. Major problems in current commercial biosensor design arise because of instability, slow response, and lack of direct, efficient electrical coupling between the enzyme and the electrode surface. The successful completion of this Phase I SBIR project could lead to new and efficient technologies for the production of multi-analyte sensors with desirable characteristics.