Technology Overview – CNT Based Sensors

DWT’s chemical detection systems are based on highly sensitive, fast response sensor platform that is governed by novel functionalized carbon nanotube (CNT) based chemiresistors. With our mission to develop a low cost, portable/hand held chemical detector, in our ongoing research efforts we have developed a sensor system capable of detecting/identifying and alarming the presence of hazardous chemical vapors from a library of 16 chemicals (which is expandable when data on more chemicals is acquired) at levels less than or equal to NIOSH/OSHA permissable exposure limits (PEL) within 10 seconds after exposing to the vapor.¬†These chemicals include Hydrogen Cyanide (AC), Cyanogen Chloride (CK), Arsine, Phosgene, Chlorine, Ammonia, Hydrogen Chloride etc. Our approach is to optimize our existing technology to develop a sensor system with these new class of sensing materials and a viable platform for accurate, fast and on spot chemical detection.



enoseKey Features
  • Small Form Factor
  • “Plug and GO” ready sensor chips
  • Easily customizable¬† for variety of sensing applications ranging from Chemical Detection, Facility/Process Monitoring, Food Industry, Military Applications
Advantages of using CNT Technology over others
  • New Formulations – Enhanced Sensitivity and Selectivity (Better than IMS)
  • Fast Response Time (Less than 10 sec. compared to ~ 10 min by GC)
  • Optimized Signal Processing – Immune to ambient environmental changes (Dynamic Baseline Correction)
  • Algorithm Development – Precise Alarm (no false) and Agent Identification
  • Effective Micro-sensor packaging – Array of 16 Sensors on each sensor substrate
  • Low Power Consumption (Compared to Optical Spectroscopic techniques)
  • Smaller Footprint and Cost Reduction


  • sensorapplicationsMILITARY APPLICATIONS: On Spot Nerve Agent / Toxic Chemical Sensors for Army, CNT Sensor Based RFID Tags for Filters
  • INDUSTRIAL APPLICATIONS: Facility / Plant Monitoring
  • COMMERCIAL APPLICATIONS: CNT Sensor based RFID Tags on Fruits to indicate Ripening, RFID Tags on Food to indicate freshness


We have done extensive in house chemical exposure testing on our sensors in order to determine their true limits. As shown here, each sensor quickly generates a fairly strong and unique signal upon exposure of a TIC enabling fast identification of such events as soon as they occur.




  • Analyzes response pattern of CNT sensors
  • Identifies which (if any) target checmical is present
  • Generates Alarm
  • Indicates identified chemical
  • Can be custom tailored for detection of specific gases
  • Dynamic background correction and normalization
  • Algorithm analyzes signal kinetics, trend, strength and pattern