Detection and Quantification through a Lipid Membrane Using the Molecularly Controlled Semiconductor Resistor
Detection and Quantification through a Lipid Membrane Using the Molecularly Controlled Semiconductor Resistor
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DOI：
10.1021/la203502b
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发表时间：
2012-01-10
期刊：
影响因子：
3.9
通讯作者：
Naaman, Ron
中科院分区：
文献类型：
--
作者：
Bavli, Danny;Tkachev, Maria;Naaman, Ron
检测分子和生物膜之间的共价和非共价结合事件是当代生物化学和分析化学的基本目标。目前，这些研究通常使用荧光方法，表面等离子体共振光谱和电化学方法进行。然而，仍然需要新的灵敏的可重复检测方法，其中样品不必转移到传感器，但是传感器可以与所研究的样品接触。我们提出了一种新的方法，用于检测和量化的过程中发生的表面上的脂质双层膜，通过监测电流的变化，通过n型GaAs为基础的分子控制的半导体电阻器（MOCSER），膜上吸附。由于GaAs在含水环境中易受蚀刻，因此在器件上沉积了甲氧基硅烷的保护薄膜。该系统被发现是足够敏感的，以允许监测pH值的变化和在膜的顶部上的水溶液中的氨基酸的浓度。当生物素化的脂质被纳入膜中时，可以监测链霉亲和素或亲和素的结合。用生物素-链霉亲和素复合物修饰的装置能够以高灵敏度和选择性检测链霉亲和素抗体与固定化链霉亲和素的结合。响应取决于分析物上的电荷。这些结果开辟了一条简单的蛋白质膜相互作用的电检测的道路。
The detection of covalent and noncovalent binding events between molecules and biomembranes is a fundamental goal of contemporary biochemistry and analytical chemistry. Currently, such studies are performed routinely using fluorescence methods, surface-plasmon resonance spectroscopy, and electrochemical methods. However, there is still a need for novel sensitive miniaturizable detection methods where the sample does not have to be transferred to the sensor, but the sensor can be brought into contact with the sample studied. We present a novel approach for detection and quantification of processes occurring on the surface of a lipid bilayer membrane, by monitoring the current change through the n-type GaAs-based molecularly controlled semiconductor resistor (MOCSER), on which the membrane is adsorbed. Since GaAs is susceptible to etching in an aqueous environment, a protective thin film of methoxysilane was deposited on the device. The system was found to be sensitive enough to allow monitoring changes in pH and in the concentration of amino acids in aqueous solution on top of the membrane. When biotinylated lipids were incorporated into the membrane, it was possible to monitor the binding of streptavidin or avidin. The device modified with biotin-streptavidin complex was capable of detecting the binding of streptavidin antibodies to immobilized streptavidin with high sensitivity and selectivity. The response depends on the charge on the analyte. These results open the way to facile electrical detection of protein membrane interactions.