Wearable Environmental Sampler with Micro-Fabricated Pre-Concentrator

A micro fabricated pre-concentrator chip (μPC) with a sorbent bed having Tenax TA (Sigma-Aldrich, St. Louis, MO) was used in our wearable environmental sampler for this study, as described previously^{20 (link)}. Briefly, the μPC was fabricated using lithography followed by etching the cavities for the sorbent bed into glass substrates. Heaters were added to the backside of the bonded μPC to achieve rapid heating of the sorbent cavity to desorb the VOCs for detection. The sampler is small and light enough to use as a wearable device and μPCs can be easily interchanged for sampling over discrete time intervals. The sampler can be programmed for a desired duration of sampling at different flow rates and records GPS, temperature and humidity data into a SD card during each sampling session. Detailed engineering design of our wearable environmental sampler and the micro-fabrication of the pre-concentrator chip (μPC) are published previously^{12 (link), 20 (link)}.