A Quarter Sized Optical NEMS Based Methyl Salicylate Detector

The objective of Imaginative Technologies, LLC teamed with Yale University is to design and build a “breadboard”, real time, optical NEMS Based Methyl Salicylate Detector (MSD), capable of measuring the presence and concentration of a chemical agent simulant (methyl salicylate – MeS) beneath a protective garment. This proposed device, MSD, will be the size of a quarter so it may be comfortably placed in a number of body regions and be able to detect and accurately identify methyl salicylate – MeS levels through the protective garment within ten seconds. The proposed detector, MSD, will have the following additional characteristics: 1) will provide a 500 nanograms (ng) to 100 milligrams (mg) per cubic meter range of response, 2) will function accurately in a rapidly fluctuating (concentration and air flow) environment and operate from 0 to 40 degrees Celsius in a high humidity (>90% Relative Humidity) environment 3) will not be adversely impacted as a result of exposure to environmental factors including human sweat, and human body odors. 4) will integrate with required central data telemetry and/or have a data logging system and sufficient on-board power for a mission duration of 4 to 8 hours. This novel micro detector will be based on a Nano Electro-Mechanical Systems (NEMS) implementation consisting of a chip-based nano-cantilever system. The ability to achieve the required sensitivities and accuracies for the exposure concentrations is a critical milestone in this development effort. The resultant sensors will be capable of operating while worn by human test subjects wearing protective garments and performing physical activity. Owing to its miniature size, MSD can be easily placed in a number of critical body regions were the a protective garment is likely to leak and track leak flow patterns in order to monitor sensitive regions. The MSD will not inhibit free movement of the test subject, and not attenuate, enhance or redirect normal circulation of air beneath the garment In this investigation, a NEMS based optical cantilever (resonator) with a tailored surface chemistry will be utilized as the MeS sensor. The detection principle is based upon the high mass sensitivity of nanomechanical devices. The readout of the cantilever is performed by integrated photonic circuitry that operates by transmitting light that is guided on a chip through patterned ridge waveguides.