Anhydrosugars are thermal degredation products of cellulose and hemicellulose. They form an important fraction of water-soluble organic carbon in atmospheric aerosols and thus have a great potential of affecting, among others, cloud formation and precipitation and thus the climate in general.
The analytical method couples ion chromatography with a highly sensitive pulsed amperometric detector (IC-PAD). In the test, a Metrosep A Supp 15 – 150 was coupled to a Metrosep Carb 1 – 150. The calibration for the anhydrosugars and sugar alcohols is linear over a wide concentration range. Less than 17 minutes were needed to achieve separation with a limit of detection (LOD) for levoglucosan of approximately 5 ng/m3.
For sample preparation, the aerosol fraction of a defined air volume is collected on a filter. Before extraction, this filter is divided in samples of a standardized size. After addition of ultrapure water, the filters are treated by ultrasonic extraction for about 30 minutes. Prior to injection, the samples are either filtrated through a syringe filter or by using Metrohm’s Inline Ultrafiltration.
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