Accelerated solid-phase dynamic extraction of toluene from air.
Solid-phase dynamic extraction (SPDE) belongs to the most innovative sample preparation and enrichment techniques. However, there is still a lack of knowledge on the fundamentals of SPDE and its applicability in the field of environmental monitoring. A homemade sampling device is constructed to make a detailed study of SPDE kinetics for toluene extraction. It proved that at least 50 aspirating and dispensing cycles were necessary to obtain toluene equilibration between gas and coating phase. A mechanistic model is proposed to explain that in every dispensing step during SPDE, significant losses of retained analytes (up to 48%) occur due to desorption processes. A new accelerated solid-phase dynamic extraction procedure (ASPDE) has been developed that avoids dispensing stages during extraction. The resulting extraction time proves to be 1.7 min, being a reduction by a factor of 37 compared with the SPDE extraction time. ASPDE proved to have high potential in ambient/indoor air monitoring. The limit of detection for toluene was determined to be 56 ppb(v), i.e. a factor of respectively, 6 and 35 lower than obtained with SPME and conventional headspace sampling with gas syringe.
Van Durme
Jim
J
Research Group EnVOC, Department of Organic Chemistry, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
Demeestere
Kristof
K
Dewulf
Jo
J
Ronsse
Frederik
F
Braeckman
Leentje
L
Pieters
Jan
J
Van Langenhove
Herman
H
D000393:Air Pollutants / Q000032:analysis*; D002849:Chromatography, Gas / Q000379:methods; D008962:Models, Theoretical; D052616:Solid Phase Extraction / Q000379:methods*; D014050:Toluene / Q000302:isolation & purification*; D014835:Volatilization
D000393:Air Pollutants; D014050:Toluene