Microfluidic paper-based analytical device for particulate metals.
Mentele-MM; Cunningham-J; Koehler-K; Volckens-J; Henry-CS
Anal Chem 2012 May; 84(10):4474-4480
A microfluidic paper-based analytical device (ÁPAD) fabricated by wax printing was designed to assess occupational exposure to metal-containing aerosols. This method employs rapid digestion of particulate metals using microliters of acid added directly to a punch taken from an air sampling filter. Punches were then placed on a ÁPAD, and digested metals were transported to detection reservoirs upon addition of water. These reservoirs contained reagents for colorimetric detection of Fe, Cu, and Ni. Dried buffer components were used to set the optimal pH in each detection reservoir, while precomplexation agents were deposited in the channels between the sample and detection zones to minimize interferences from competing metals. Metal concentrations were quantified from color intensity images using a scanner in conjunction with image processing software. Reproducible, log-linear calibration curves were generated for each metal, with method detection limits ranging from 1.0 to 1.5 Ág for each metal (i.e., total mass present on the ÁPAD). Finally, a standard incineration ash sample was aerosolized, collected on filters, and analyzed for the three metals of interest. Analysis of this collected aerosol sample using a ÁPAD showed good correlation with known amounts of the metals present in the sample. This technology can provide rapid assessment of particulate metal concentrations at or below current regulatory limits and at dramatically reduced cost.
Aerosols; Chemical-composition; Analytical-processes; Hydrogen-ion-activity; Iron-compounds; Metal-compounds; Metallic-compounds; Nickel-compounds; Exposure-levels; Particulates; Particulate-dust; Air-sampling; Air-samples; Filters; Copper-compounds
Charles S. Henry, Department of Chemistry and Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523
7440-02-0; 7439-89-6; 7440-50-8
Grant-Number-R21-OH-010050; Grant-Number-T42-OH-009229; B10152012
Colorado State University - Fort Collins