A Nanotip Array Based Biological Pathogen Sensor – IP 0914

The invention is a real time pathogen detection system fordetecting deadly pathogens such as anthrax, ebola, botulism, smallpox, amongothers. The system can also measure concentrations of the pathogen. The systemis portable – if an external power source is available in the location it is tobe used in, it can fit into a briefcase. Its response time is expected to be intens of seconds. Additionally, the device produces no waste to dispose of andrequires no reagents. There are two modes of operation of this device: 1) As astand alone physical sensor where the nanotip electrodes are charged with abias to produce an electric field to adsorb the unknown species in the media(air, gas, vapor, liquid) on the tips. After adsorption the species, if largeenough to bridge the gap between the tip and the ground plane, is swept with abias and the current is measured and/or at the same time a photonic stimulus isapplied and the response current versus applied bias and the wavelength of thephotonic stimulus is measured. This allows a rapid, wide spectrum “smokedetector” type of response identifying the presence of a potential pathogen andhighlighting possible species present. 2) As a loaded DNA or antigen type ofhighly specific pathogen sensor. In this mode of operation the nanotipelectrodes of this device are biased to create a small electric field. Thissmall electric field causes user introduced, pathogen species specific, DNA oran antigen to bind to the nanotip electrode. Subsequently, the unidentified potentialpathogens enter the sensor chamber and bind to either the antigen or DNAfragment. The bias voltage on the nanotip electrodes is then swept while thepathogen is bound to the electrodes. The presence of the pathogen produces acharacteristic change in the current vs. voltage response between theelectrodes. Each pathogen will produce a signature response that is compared toa database of known and previously recorded responses to identify the pathogen.The DNA/antigen is selective in the first place, so the current-voltageresponse is secondary means for confirming the presence of the pathogen. Aphotonic stimulus can also be applied to the captured pathogen; voltage andcurrent can then be measured as a function of the photonic stimulus wavelength asan additional means for identifying pathogens. Shantanu Balkundi sbalkund@fiu.edu 305-348-8061