Paper-based analytical devices with colorimetric detection for determining levoglucosan in atmospheric particulate matter

Abstract

Levoglucosan is used as a tracer of biomass burning; however, its determination often requires expensive analytical techniques. Therefore, this study describes the development of an inexpensive and useful method using paper-based analytical devices (PADs) to determine levoglucosan based on colorimetric measurements. The color intensities were correlated with the analytical concentrations and presented linear behavior in the range from 0 to 64.8 μg mL−1. The achieved limits of detection and quantification were 2 and 6 μg mL−1, respectively. The conversion rate of levoglucosan into glucose was 81 ± 8% and the average recovery was 105 ± 9%. Moreover, the method presented selectivity for levoglucosan, showing variation in colorimetric signal intensity lower than 8% in the presence of other saccharides (xylose, glucose, galactose, maltose, mannose, arabinose, and fructose). The accuracy of the method was confirmed by comparison with gas chromatography-mass spectrometry. The proposed method was explored to determine levoglucosan in samples of atmospheric particulate matter collected in Goiania city (Brazil) and the values ranged from 0.08 to 1.10 μg m−3, showing the high impact of the biomass burning to the particulate matter in the region's atmosphere. The method was also used to detect levoglucosan in rainwater samples. Therefore, the use of PADs can simplify fieldwork involving the determination of levoglucosan in atmospheric particulate matter.