Determinação de levoglucosano em material particulado atmosférico e água de chuva utilizando dispositivos analíticos fabricados em papel

• Autor(a) principal: Dias, Isabela Milhomem
• Data de Publicação: 2018
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/0013000006vpd
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/8459
• topic: Levoglucosano; Queima de biomassa; PAD; Levoglucosan; Biomass burning; CIENCIAS EXATAS E DA TERRA::QUIMICA

Air pollution is an environmental problem present in many regions of the world. Aerosols or particulate matters (PM) are atmospheric pollutants associated with climate changes and human health, and prompt a great number of deaths each year. In Brazil, the forest fires and the burning of sugarcane are some of the sources of emissions of gases and PM into the atmosphere. The anhydrosugar levoglucosan and its stereoisomers, mannosan and galactosan, are biomass burning markers, because they are produced by cellulose pyrolysis at high temperatures. This work developed a method using Paper-based Analytical Devices (PADs) with colorimetric detection to determine biomass burning markers in samples of PM and rainwater of Goiânia city. In this method, the levoglucosan present in the samples was hydrolyzed to glucose, and after an enzymatic reaction, showed a magenta coloration using a chromogen agent. The PADs were scanned generate a digital image, and the color intensities were correlated with the analyte concentrations. The method showed a conversion rate of levoglucosan to glucose of 81%, good linearity in the range of 0 to 0.4 mmol.L-1 , a limit of detection (LD) of 2 μg.mL-1 and a limit of quantification (LOQ) of 6 μg.mL-1 for hydrolysis in sulfuric acid. Moreover, the method presented selectivity for these markers, because the interferents can be detected and quantified. The concentrations of levoglucosan determined in PM were high and varied from 0.08 to 1.10 μg.m-3 (0.44 ± 0.29; n = 10), these concentrations were similar to those obtained in the Amazon, which is a region exposed to extensive biomass burning due to deforestation. In rainwater samples, collected in two different events, levoglucosan was detected showing that biomass burning has a significant contribution in the emission of gases and PM in Goiânia atmosphere. The method developed in this work using PADs with colorimetric detection was successfully apllied to levoglucosan determination in PM and rainwater samples. This process used low volume of samples and reagents, the analysis are rapid, the operation is easy, the cost of production is low and the devices are portable, being an advantageous technique.