Direct ultrasonic agitation for rapid extraction of organic matter from airborne particulate

Direct ultrasonic extraction (DUE) is proposed as simple and rapid sample p retreatment method. This new approach is applied to the extraction of parti culate organic matter (POM) from airborne particulate by using dichlorometh ane (DCM) or DCM/methanol (90/10, v/v) as extractant. The analytical determ ination was carried out by weighing the extractable POM on an electrobalanc e. Total recovery for POM could be obtained when the sample was extracted t hree times with 25-50 mL extractant each for about 5 min at 50 W ultrasonic power. In comparison with conventional Soxhlet extraction, less extraction time (total 15 min only) and solvent consumption(100 mL) were required by DUE. The efficiency of the DUE was similar or even higher than the routine Soxhlet method. Additionally, the new extractor is very simple and easy to use and can accelerate the extraction procedures of organic components from various solid samples.