This project proposes building controlled single-walled carbon nanotube (SWNT) arrays at the wafer scale toi[unreadable] obtain large arrays of nanosensor devices and use them to detect biological molecules in solutions with a[unreadable] focus on protein detections. Specific aims will include, (1) Construction and testing of nanotubes/nanowire[unreadable] sensors with aptamer or antibody based recognition of protein via combined electronic and fluorescence[unreadable] detections for and on the sensor array devices. (2) Development of bio-molecule multiplexing strategies for[unreadable] nanotube/nanowire sensor arrays in solution phase without drying the proteins or antibodies on the arrays to[unreadable] prevent protein denaturing. (3) Use both fluorescence detection and SWNT or NW transistor electrical[unreadable] detection scheme to explore the pros and cons for each method. (4) Develop multiplexing methods using[unreadable] electrical and/or electrochemical control of each device in a sensor array. This will enable multiplexing[unreadable] without drying of proteins and afford high density protein nano-arrays. The spatial chemical resolution will[unreadable] then be controlled electrically, an unique feature for electrically active sensors such as SWNTs and[unreadable] nanowires. (5) Testing of nanowire arrays with mouse serum samples. (5) Testing of nanowire arrays with[unreadable] human serum samples of cancer patients. (6) Close collaboration between nano-scientists (Dai), oncologists[unreadable] and clinic experts (Felsher, Utz). The nanosensor arrays will be closed compared with existing protein[unreadable] micro-array technology to identify key advantages of nanosensors and develop nanoscale tools and sensing[unreadable] platforms that can solve key problems in microarrays. We expect the advantages will include electrical[unreadable] control of chemical immobilization and multiplexing, high density, arraying without drying for proteins and[unreadable] electrical transistor sensing scheme. The bio-functionalized nanotube-sensor chips will be used for detecting[unreadable] antibody-antigen binding, ligand- or peptide-protein binding. The specific systems that will be used for the[unreadable] nanosensor development will be streptavidin with biotin for year 1, tenascin-C with aptamer and antibody[unreadable] probes for year 2-3 and Her-kinase patterns with aptamter and antibody probes for year 3-5. In comparison[unreadable] to nanowire sensing research in other groups, the key uniqueness of our project is that first, we are inclusive[unreadable] of using optical fluorescence detection for nanosensors in addition to electrical detection. We will use the[unreadable] electrical degree of freedom for biomolecular multiplexing and sensing. Secondly, we have protein[unreadable] microarray expert in our team and the outcome of our research project will be to enable a nanotechnology[unreadable] significantly more advanced than the current micro-arrays. Thirdly, we will use large numbers of nanotubes[unreadable] and nanowires for each sensor site in the array to build redundancy, reduce background noise and optimize[unreadable] sensitivity. All of the reported nanowire sensors thus far use a single nanowire for each sensing site and has[unreadable] high noise and low stability.