Electronic Detection of BioMolecules

本项目的重点是利用纳米尺度的电子结构研究生物分子的构象动力学，其中传感元件是碳纳米管或纳米管网络。这种传感器体积小、速度快(有效区域与单个蛋白质或DNA兼容)，而且非常敏感，因为所有电流都在纳米管传导通道的表面流动，从而通过检测点。这项研究的目的是将这些纳米级的电子设备用作生物传感器，并探索它们在缓冲环境中实时检测生物分子构象变化的潜力。将探索三个领域。首先，将使用不同长度和序列的寡聚体来检查双链的形成以及DNA双链的融化。其次，将使用生物素-链霉亲和素，配体-受体模型系统来研究蛋白质之间的相互作用。以细菌视紫红质为模型系统，探讨检测构象变化的可行性。第三，将使用单个纳米管跨越电子设备的源极和漏极的设备来实时监测与纳米管结合的蛋白质的直接检测以及随后的构象变化。电子探测实验将与光谱测量和设备的直接成像一起进行。在更广泛的意义上，电子检测计划可以在生物技术的不同领域提供光学检测的替代方案，包括基因芯片和蛋白质芯片，以及医疗诊断。将探索的电子检测方案可以补充其他单分子检测技术，包括光学方法、ESR和核磁共振技术。

This project focuses on the investigation of conformational dynamics of biomolecules using nanoscale electronic structures where the sensing element is a carbon nanotube or a nanotube network. Such sensors are small and fast (the active area is compatible with individual proteins or DNA) and are extremely sensitive since all the current flows at the surface of the nanotube conducting channel, and thus passes through the detection point. The objective of the research is to use these nanoscale electronic devices as bio-sensors and also explore their potential in real-time detection of conformational changes of biomolecules in a buffer environment. Three areas will be explored. First, duplex formation as well as the melting of the DNA duplex will be examined using oligomers of different lengths and sequences. Second, interactions between proteins will be studied using the biotin-streptavidin, ligand-receptor model system. The feasibility of detecting conformational changes will be explored using bacteriorhodopsin as a model system. Third, direct detection of protein binding to nanotubes, and the subsequent conformational changes, will be monitored in real time using devices where individual nanotubes span the source and drain of the electronic device. Experiments on electronic detection will be conducted hand-in-hand with spectroscopic measurements and with direct imaging of the devices. In the broader sense, electronic detection schemes may offer alternatives of optical detection in diverse areas of biotechnology, including gene chips and protein chips, and also medical diagnostics. The electronic detection schemes to be explored may complement other single molecule detection techniques, including optical methods, ESR and NMR techniques.