Chemiresistors: Low Cost and Near Zero Power Sensors

T.M. Swager
Massachusetts Institute of Technology,
United States

Keywords: chemiresistor, carbon nanotube, low power, RFID

Summary:

Chemiresistive sensors that function at ambient temperature can, with proper chemical design, have high selectivity and sensitivity. Designs for carbon nanotube systems that display these attributes and function at ultra-low power will be discussed. The field of chemiresistors and sensors in general has generally suffered from a lack of selectivity. New structures, concepts, and reactions that create high selectivity for analytes of interest will be presented. Resistance measurements are easily made with battery operated readers that are inexpensive and could be broadly deployed in the developing world. Additionally, we have extended this platform to passive RFID devices that can be read by conventional modern smartphones that have near field capabilities and can be functionalized with chemiresistive materials that are selective for disease biomarkers. The passive RFID devices are cost less than $0.25 each and the connectivity to the cloud via a cellular signal allows for remote data analysis and spatial temporal correlations to be made.