Development of recognition device for biomolecules using polymer gel-QCM conjugate

首先，以N-异丙基丙烯酰胺及其共聚物为原料，在石英晶体微天平表面合成了微尺寸水凝胶。物理附着在石英微球表面的凝胶在石英的振动作用下表现出良好的粘弹性。金电极更适合于微凝胶在QCM上的物理附着。建立了牛血清白蛋白的导入方法。蛋白质通过化学共价键结合到凝胶的聚合物网络中。研究了微凝胶的相行为和QCM响应随溶液pH、离子强度和溶液温度的变化。具有5 MHz基本谐振频率的QCM对环境变化的响应速度快，灵敏度高。由于凝胶在环境中的粘弹性变化，QCM的共振频率和粘度项发生了变化。与非常少量的有机分子接触的凝胶响应于各种浓度的有机分子。当引入的蛋白质的抗体与蛋白质相互作用时，凝胶的粘弹性敏感地响应于QCM共振的变化。研究结果表明，微凝胶与QCM的耦合是一种潜在的高灵敏度分子传感器件。

First, method to synthesized micro size hydrogels on the surface of quartz crystal microbalance, QCM, was developed using N-isopropylacrylamide and its copolymer. The gel physically attached on the surface of QCM worked well as a visco-elastic body under the vibration of the quartz. The gold electrode was preferable for the physical attachment of microgel on the QCM. The method to introduce bovine serum albumin was developed. The protein was introduced into the polymer network of gel chemically through covalent bonding. The phase behavior and QCM response of the microgel were investigated as a function of solution pH, ionic strength and solution temperature. The QCM with 5MHz basic resonation responded with high sensitivity to the environmental change quickly. The change in resonation frequency and viscosity term of the QCM appeared due to the visco-elasitic property change of the gel in the environment. The gel contact with very small amount of organic molecules responded for a wide variety of concentration of the organic molecules. When a anti-body of introduced proteins interacted with the protein, the visco-elasticity of the gel responded sensitively with change in resonation of the QCM. The results obtained in the present study indicated that the micro gel coupled with the QCM was potential device for molecular sensing with high sensitivity.