Influence of polydimethylsiloxane outer coating and packing material on analyte recovery in dual-phase headspace sorptive extraction.
Dual phase twisters (DP twisters), consisting of a polydimethylsiloxane (PDMS) outer coating and a second complementary (ad)sorbent as inner packing, have recently been shown to extend the applicability of headspace sorptive extraction (HSSE). In comparison to HSSE using PDMS only, the recovery of analytes from the headspace of a solid or liquid matrix is increased by combining the concentration capabilities of two sampling materials operating on different mechanisms (sorption and adsorption). This study compares the performance of DP twisters consisting of different PDMS outer coatings and different packing materials, including Tenax GC, a bisphenol-PDMS copolymer, Carbopack coated with 5% of Carbowax and beta-cyclodextrin, for the analysis of the headspace of roasted Arabica coffee, dried sage leaves and an aqueous test mixture containing compounds with different water solubility, acidity, polarity and volatility as test samples. In general, DP twisters showed a higher concentration capability than the corresponding conventional PDMS twisters for the analytes considered. The highest recoveries were obtained with DP twisters consisting of 0.2mm thick PDMS coating combined with Tenax GC, a bisphenol-PDMS copolymer and Carbopack coated with 5% of Carbowax as inner adsorption phase.
Bicchi
Carlo
C
Dipartimento di Scienza e Tecnologia del Farmaco, Università degli Studi di Torino, via P Giuria 9, I-10125, Turin, Italy. carlo.bicchi@unito.it
Cordero
Chiara
C
Liberto
Erica
E
Sgorbini
Barbara
B
David
Frank
F
Sandra
Pat
P
Rubiolo
Patrizia
P
D005591:Chemical Fractionation / Q000379:methods*; D002849:Chromatography, Gas / Q000379:methods*; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D015203:Reproducibility of Results; D012828:Silicones / Q000737:chemistry*
D004129:Dimethylpolysiloxanes; D012828:Silicones; C013830:baysilon