Development of stir-bar sorptive extraction-thermal desorption-gas chromatography-mass spectrometry for the analysis of musks in vegetables and amended soils.
The aim of this study was to develop a sensitive and environment-friendly method based on stir-bar sorptive extraction (SBSE) followed by thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) to determine 8 synthetic musks (musk ambrette, musk ketone, celestolide, tonalide, galaxolide, phantolide, traseolide, and cashmeran) in vegetables (lettuce, carrot, and pepper) and amended soil samples. In a first step sorptive extraction was studied both in the headspace (HSSE) and in the immerse mode (SBSE). The best results were obtained in the immersion mode which was further studied. The influence of the main factors: methanol (20%) and NaCl addition (0%), extraction temperature (40°C) and time (180 min), extraction solvent volume (9 mL) and stirring rate (600 rpm) on the efficiency of SBSE was evaluated by means of experimental designs. In the case of TD, desorption time (10 min), desorption temperature (300°C), cryo-focusing temperature (-30°C), vent flow (75 mL/min) and vent pressure (7.2 psi) were studied using both a fractioned factorial design and a central composite design (CCD). The method was validated in terms of apparent recoveries (AR%), method detection limits (MDLs) and precision at two different concentration levels. Although quantification using instrumental calibration rendered odd results in most of the cases, satisfactory recoveries (74-126%) were obtained in the case of matrix-matched calibration approach for all of the analytes and matrices studied at the two concentration levels evaluated. MDLs in the range of 0.01-0.8 ng/g and 0.01-1.1 ng/g were obtained for vegetables and amended soil samples, respectively. RSD values within 1-23% were obtained for all the analytes and matrices. Finally, the method was applied to the determination of musks in vegetable and amended soil samples.
Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, Bilbao 48080, Spain.
Josu
J
Aguirre
Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, Bilbao 48080, Spain.
Ekhiñe
E
Bizkarguenaga
Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, Bilbao 48080, Spain.
Arantza
A
Iparraguirre
Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, Bilbao 48080, Spain.
Luis Ángel
LÁ
Fernández
Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, Bilbao 48080, Spain.
Olatz
O
Zuloaga
Department of Analytical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), P.O. Box 644, Bilbao 48080, Spain. Electronic address: ailette.prieto@ehu.es.
Ailette
A
Prieto
D004129:Dimethylpolysiloxanes / Q000737:chemistry; D005229:Fatty Acids, Monounsaturated / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D000432:Methanol / Q000737:chemistry; D015203:Reproducibility of Results; D012965:Sodium Chloride / Q000737:chemistry; D012987:Soil / Q000737:chemistry*; D014675:Vegetables / Q000737:chemistry*
D004129:Dimethylpolysiloxanes; D005229:Fatty Acids, Monounsaturated; D012987:Soil; C008563:musk; D012965:Sodium Chloride; C013830:baysilon; D000432:Methanol
Amended soil; Musks; Stir-bar sorptive extraction; Thermal desorption; Vegetables