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J Chromatogr A

Title:		Polydimethylsiloxane-based permeation passive air sampler. Part II: Effect of temperature and humidity on the calibration constants
Author(s):		Seethapathy S; Gorecki T;
Address:		"Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada"
Journal Title:		J Chromatogr A
Year:		2010
Volume:		20101021
Issue:		50
Page Number:		7907 - 7913
DOI:		10.1016/j.chroma.2010.10.057
ISSN/ISBN:		1873-3778 (Electronic) 0021-9673 (Linking)
Abstract:		"Polydimethylsiloxane (PDMS) has low permeability towards water vapour and low energy of activation of permeation towards volatile organic compounds (VOCs) when compared to many other polymers. Suitability of the material for use in permeation-type passive air samplers was tested as it theoretically should reduce uptake rate variations due to temperature changes and eliminate or reduce complications arising from sorbent saturation by water vapour. The calibration constants of a simple autosampler vial-based permeation passive sampler equipped with a PDMS membrane (Waterloo Membrane Sampler((R))) were determined for various analytes at different temperatures. From the data, the activation energy of permeation for PDMS towards the analytes was determined. The analytes studied belonged to various classes of compounds with wide ranging polarities, including n-alkanes, aromatic hydrocarbons, esters and alcohols. The results confirmed Arrhenius-type relationship between temperature and calibration constant and the energy of activation of permeation for PDMS ranged from -5kJ/mole for butylbenzene to -17kJ/mole for sec-butylacetate. Calibration constants of the samplers towards n-alkanes and aromatic hydrocarbons determined at humidities between 30% and 91% indicated no statistically significant variations in the uptake rate with changes in humidity for 9 of the 11 analytes studied. The results confirmed the suitability of the sampler for deployment in high humidity areas and under varying temperature conditions"
Keywords:		"Air/analysis Algorithms Analysis of Variance Calibration Chromatography, Gas/*methods Dimethylpolysiloxanes/*chemistry Environmental Monitoring/*instrumentation/methods Humidity Hydrocarbons/chemistry Permeability Temperature Volatile Organic Compounds/ch;"
Notes:		"MedlineSeethapathy, Suresh Gorecki, Tadeusz eng Research Support, Non-U.S. Gov't Netherlands 2010/11/12 J Chromatogr A. 2010 Dec 10; 1217(50):7907-13. doi: 10.1016/j.chroma.2010.10.057. Epub 2010 Oct 21"