Science Inventory

Microfabricated Air-Microfluidic Sensor for Personal Monitoring of Airborne Particulate Matter: Design, Fabrication, and Experimental Results

Citation:

Paprotnyla, I., F. Doering, P. Solomon, R. White, AND L. Gundel. Microfabricated Air-Microfluidic Sensor for Personal Monitoring of Airborne Particulate Matter: Design, Fabrication, and Experimental Results. Sensors and Actuators A: Physical. Elsevier BV, AMSTERDAM, Netherlands, 201:506-516, (2013).

Impact/Purpose:

The National Exposure Research Laboratory′s (NERL′s) Human Exposure and Atmospheric Sciences Division (HEASD) conducts research in support of EPA′s mission to protect human health and the environment. HEASD′s research program supports Goal 1 (Clean Air) and Goal 4 (Healthy People) of EPA′s strategic plan. More specifically, our division conducts research to characterize the movement of pollutants from the source to contact with humans. Our multidisciplinary research program produces Methods, Measurements, and Models to identify relationships between and characterize processes that link source emissions, environmental concentrations, human exposures, and target-tissue dose. The impact of these tools is improved regulatory programs and policies for EPA.

Description:

We present the design and fabrication of a micro electro mechanical systems (MEMS) air-microfluidic particulate matter (PM) sensor, and show experimental results obtained from exposing the sensor to concentrations of tobacco smoke and diesel exhaust, two commonly occurring PM sources. Our sensor measures only 25 mm × 21 mm × 2 mm in size and is two orders of magnitude smaller than commercially available direct mass PM sensors. The small shape allows our sensor to be used for continuous recording of personal PM exposure levels. The sensor contains an air-microfluidic circuit that separates the particles by size (virtual impactor) and then transports and deposits the selected particles using thermophoretic precipitation onto the surface of a microfabricated mass-sensitive film bulk acoustic resonator (FBAR). The mass-loading of the FBAR causes a change in its resonant frequency, and the rate of the frequency change corresponds to the particle concentration in the sampled air-volume. We present experimental results that demonstrate the performance of our sensor for measuring PM-mass emitted from diesel exhaust and tobacco smoke, and show that it exhibits low-end sensitivity on the order of 2 μg/m3 with up to 10 min integration time.

Record Details:

Record Type:DOCUMENT( JOURNAL/ PEER REVIEWED JOURNAL)
Product Published Date:10/15/2013
Record Last Revised:09/10/2014
OMB Category:Other
Record ID: 261776