A microfluidic paper-based analytical device for rapid quantification of particulate chromium.
Rattanarat P; Dungchai W; Cate DM; Siangproh W; Volckens J; Chailapakul O; Henry CS
Anal Chim Acta 2013 Oct; 800:50-55
Occupational exposure to Cr is concerning because of its myriad of health effects. Assessing chromium exposure is also cost and resource intensive because the analysis typically uses sophisticated instrumental techniques like inductively coupled plasma-mass spectrometry (ICP-MS). Here, we report a novel, simple, inexpensive microfluidic paper-based analytical device (µPAD) for measuring total Cr in airborne particulate matter. In the µPAD, tetravalent cerium (Ce(IV)) was used in a pretreatment zone to oxidize all soluble Cr to Cr(VI). After elution to the detection zone, Cr(VI) reacts with 1,5-diphenylcarbazide (1,5-DPC) forming 1,5-diphenylcarbazone (DPCO) and Cr(III). The resulting Cr(III) forms a distinct purple colored complex with the DPCO. As proof-of-principle, particulate matter (PM) collected on a sample filter was analyzed with the µPAD to quantify the mass of total Cr. A log-linear working range (0.23-3.75µg; r(2)=0.998) between Cr and color intensity was obtained with a detection limit of 0.12µg. For validation, a certified reference containing multiple competing metals was analyzed. Quantitative agreement was obtained between known Cr levels in the sample and the Cr measured using the µPAD.
Chromium-compounds; Analytical-chemistry; Analytical-instruments; Analytical-processes; Metal-compounds; Metallic-compounds; Particulates; Particulate-dust; Particulate-sampling-methods; Quantitative-analysis; Fluids; Airborne-particles; Oxidizers; Sample-preparation; Filters;
Author Keywords: Paper-based analytical device; Microfluidics; Chromium; Particulate matter
John Volckens, Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523
7440-47-3; 16065-83-1; 18540-29-9; 1333-82-0
Analytica Chimica Acta
Colorado State University - Fort Collins