Wearable Photoelectrocatalytic Personal Environmental Exposure Monitor

Period of Performance: 09/01/2008 - 08/31/2009


Phase 1 SBIR

Recipient Firm

Valencell, Inc.
2800-154 sumner blvd
Raleigh, NC 27616
Principal Investigator


DESCRIPTION (provided by applicant) Conventional environmental exposure monitoring requires bulky instrumentation without providing a personalized history of environmental exposure. Valencell's long-term goal is to provide a noninvasive, low-profile, real-time, affordable personal environmental exposure monitor platform that is virtually unnoticed by the user for maximum performance and convenience. This platform will provide a quantitative, reliable, in-field measurement of personal-level, point-of-contact exposure to a variety of airborne chemical toxins of particular interest to health conscious end-users, sports enthusiasts, the immunocompromised, and medical professionals. Integrated Bluetooth communication protocols will be employed towards sending real-time information wirelessly to a cell phone or PDA. In turn, this information can then be sent wirelessly to online databases for storing and processing information relating personal health with personal environmental factors and user demographics. The specific goal of this Phase I feasibility study is the development of a novel sensor element providing the flexibility of monitoring volatile organic compounds (VOCs), ozone, carbon monoxide, polycyclic aromatic hydrocarbons (PAHs), and other reactive airborne species in the same compact device. Filament-heated tin oxide VOC sensors, the workhorse of solid-state VOC sensing, are sufficiently compact but require significant operating power and lack vapor specificity. Valencell's innovative approach is the development of a novel wide band gap (WBG) VOC sensor offering enhanced vapor specificity and dramatically reduced power consumption over standard metal oxide sensors. This innovation enables the development of a novel, low-power (<10 mW), real-time (<100 ms sampling), compact (< 10 cm3), wearable VOC monitor capable of long-term battery-powered operation, high specificity, and broad sensitivity (0.1 to 1000 ppm). In this program, Valencell will fabricate sensor electrodes from novel WBG metal-oxide films deposited by North Carolina State University (NCSU). The functionality of these sensor electrodes will then be validated by evaluating the sensitivity and specificity of each electrode in a bell jar VOC test bed. The sensor electrodes will then be integrated into a self-contained VOC sensor prototype such that the predicted performance specifications can be statistically validated in the VOC test bed.