Development of carbon nanotube biosensors and investigation of sensing mechanism

生物传感器是一种强大的工具，可以选择性地识别工业产品、环境样本(例如空气、土壤、水)和临床样本中的病原体(例如细菌、病毒)和有毒化学物质。新型生物传感器具有更高的灵敏度、更好的特异度和更大范围的多样性，将在推动环境监测、早期癌症诊断和基础研究方面发挥重要作用，从而提高对不可治愈疾病的理解。拟议的项目旨在开发基于单壁碳纳米管(SWNT)场效应管(FET)的新一代生物传感器和潜在的生物芯片。在SWNT-FET中，每个传导通道，一个SWNT，直径约2 nm，其大小与单个生物分子兼容。SWNT-FET器件的电导对其周围的化学和静电环境极为敏感。它允许对传感器表面上的生物事件进行直接电子检测，如DNA杂交和抗原抗体结合。潜在的应用包括：1)用于分子诊断的全电子DNA或蛋白质微阵列，它消除了对劳动密集型和昂贵的荧光标记的需要；2)环境传感器，可以在公共场所现场快速准确地识别高致病性颗粒。

Biosensors are powerful tools providing selective identification of pathogens (e.g., bacteria, virus) and toxic chemicals in industrial products, environmental samples (e.g., air, soil, water), and clinical specimens. Novel biosensors with higher sensitivity, better specificity, and larger-scale multiplicity will play an important role in advancing analysis technologies for environmental monitoring, early cancer diagnostics, and basic research towards improved understanding of untreatable diseases. The proposed project will aim at developing a new generation of biosensors, and potential biochips, based on single-walled carbon nanotube (SWNT) field effect transistors (FETs). In a SWNT-FET, each conduction channel, a SWNT, is about 2nm in diameter, which is size compatible with a single biomolecule. The electrical conductance of a SWNT-FET device is extremely sensitive to its surrounding chemical and electrostatic environment. It allows direct electrical detection of biological events, such as DNA hybridization and antigen-antibody binding, on the sensor surface. Potential applications include: 1) fully electronic DNA or protein microarrays for molecular diagnosis, which eliminates the need for labor intensive and costy fluorescence labeling; 2) environmental sensors that can rapidly and accurately identify highly pathogenic particles on-the-spot in public places.