AAAR 31st Annual Conference
October 8-12, 2012
Hyatt Regency Minneapolis
Minneapolis, Minnesota, USA
Abstract View
Paper-Based Microfluidic Devices for Aerosol Exposure Assessment
David Cate, Josephine Cunningham, Mallory Mentele, Wijitar Dungchai, Yupaporn Sameenoi, Kirsten Koehler, Charles Henry, JOHN VOLCKENS, Colorado State University
Abstract Number: 606 Working Group: Aerosol Exposure
Abstract Aerosols present health hazards in a variety of settings ranging from manufacturing to the production of food and energy. In U.S. occupational settings alone, an estimated 5 to 8 million air samples are collected annually to assess human exposure to aerosol hazards. However, our ability to associate aerosol exposure with occupational disease is hampered by limitations in existing sampling technology, especially with cost and timeliness. For example, particulate metals exposure assessment requires an 8-hour filter sample followed by analysis using inductively coupled plasma (ICP) at a cost of hundreds of dollars per sample. Furthermore, sample handling and processing times for such samples vary from days to weeks, reducing the efficiency of the risk communication process. Here, we address the need for improvements in the cost and timeliness of personal exposure assessment through the use of microfluidic paper-based analytical devices (mPAD for short). In mPADs, wax-based hydrophobic barriers are patterned onto hydrophilic filter paper to create channels for directed flow to be directed from a central sample reservoir to multiple unique detection zones. The resulting device use only small amounts (~10 microliters) of eluent, making measurement of low levels of many analytes reasonable. Finally, because the devices are made from filter paper, wax, and inexpensive chemical reagents, assay costs are less than a dollar per sample. Here we will present the development of mPADs for the analysis of aerosolized metals from welding fumes and aerosol oxidative load using filters obtained from personal exposure monitors. The mPADs we have developed allow for detection limits of 1 microgram of total mass for metals and 1 nmol of DTT consumption for oxidative activity. Furthermore, these devices are designed for sample collection and analysis in the field, providing immediate results for a given exposure assessment.