Analysis of carbamate and phenylurea pesticide residues in fruit juices by solid-phase microextraction and liquid chromatography-mass spectrometry.

A new analysis method to detect carbamates and phenylurea pesticide residues in fruit juices was developed using solid-phase microextraction (SPME) coupled with liquid chromatography-single quadrupole mass spectrometry (LC/MS) and liquid chromatography-quadrupole ion trap mass spectrometry (LC/QIT-MS). The pesticide residues present in watery matrices as fruit juices were extracted using three types of fibers: 50-microm Carbowax/templated resin (CW/TPR), 60-mum poly(dimethylsiloxane)/divinylbenzene (PDMS/DVB) and 85-microm polyacrylate. The different extraction conditions were evaluated choosing as the best parameters 90 min (time), 20 degrees C (temperature) and 1 ml (volume). After extraction, the desorption (in a static mode) was performed in the specific interface chamber SPME/HPLC, previously filled with 70% methanol and 30% water. The best recoveries, evaluated at two fortification levels (0.2 and 0.5 mg kg(-1)) in fruit juices, were obtained using PDMS/DVB and CW/TPR fibers, and ranged from 25 to 82% (monolinuron, diuron and diethofencarb), with relative standard deviations (RSDs) from 1 to 17%. All the limits of quantification (LOQs) were in the range of 0.005-0.05 microg ml(-1) and, in any case, equal to, or lower than, maximum residue limits (MRLs) established by Italian and Spanish legislations. The mass spectrometry analyses were carried out using an electrospray ionization (ESI) source operating in the positive mode both for single quadrupole and for QIT mass analysers, operating in selected ion monitoring (SIM) and in multiple reaction monitoring (MRM) modes, respectively. The proposed new method can be applied to the determination of selected pesticides in real samples of fruit juices.

[1]  G. Font,et al.  Application of solid-phase microextraction for determining phenylurea herbicides and their homologous anilines from vegetables. , 2004, Journal of chromatography. A.

[2]  J. Pawliszyn,et al.  Solid phase microextraction with thermal desorption using fused silica optical fibers , 1990 .

[3]  Y. Picó,et al.  Routine application using single quadrupole liquid chromatography-mass spectrometry to pesticides analysis in citrus fruits. , 2005, Journal of chromatography. A.

[4]  J. Pawliszyn,et al.  Automated in-tube solid-phase microextraction-high-performance liquid chromatography for carbamate pesticide analysis. , 2000, Journal of chromatography. A.

[5]  M. Careri,et al.  Development and validation of a solid phase micro-extraction-gas chromatography-mass spectrometry method for the determination of furan in baby-food. , 2006, Journal of chromatography. A.

[6]  N. Unceta,et al.  Coupling solid-phase microextraction and high-performance liquid chromatography for direct and sensitive determination of halogenated fungicides in wine. , 2003, Journal of chromatography. A.

[7]  J. Pawliszyn,et al.  Analysis of polar pesticides in water and wine samples by automated in-tube solid-phase microextraction coupled with high-performance liquid chromatography-mass spectrometry. , 2002, Journal of chromatography. A.

[8]  Y. Picó,et al.  Comparison of octadecylsilica and graphitized carbon black as materials for solid-phase extraction of fungicide and insecticide residues from fruit and vegetables. , 1997, Journal of chromatography. A.

[9]  Maurizio Quinto,et al.  Solid-phase microextraction – gas chromatography mass spectrometry: A fast and simple screening method for the assessment of organophosphorus pesticides residues in wine and fruit juices , 2004 .

[10]  G. Bending,et al.  Microbial degradation of isoproturon and related phenylurea herbicides in and below agricultural fields. , 2003, FEMS microbiology ecology.

[11]  S. Lehotay Supercritical fluid extraction of pesticides in foods. , 1997, Journal of chromatography. A.

[12]  Electron impact fragmentation of carbofuran and its major photolytic transformation metabolites , 1999 .

[13]  Kazuhiko Akutsu,et al.  Determination of neonicotinoid pesticide residues in vegetables and fruits with solid phase extraction and liquid chromatography mass spectrometry. , 2003, Journal of agricultural and food chemistry.

[14]  A. L. Simplício,et al.  Validation of a solid-phase microextraction method for the determination of organophosphorus pesticides in fruits and fruit juice. , 1999, Journal of chromatography. A.

[15]  T. Albanis,et al.  Headspace solid phase microextraction applied to the analysis of organophosphorus insecticides in strawberry and cherry juices. , 2002, Journal of agricultural and food chemistry.

[16]  H. Pylypiw,et al.  Rapid gas chromatographic method for the multiresidue screening of fruits and vegetables for organochlorine and organophosphate pesticides. , 1993, Journal of AOAC International.

[17]  G. Font,et al.  Solid-phase microextraction liquid chromatography/tandem mass spectrometry to determine postharvest fungicides in fruits. , 2003, Analytical chemistry.

[18]  A. Tejedor,et al.  Determination of imidacloprid and benzimidazole residues in fruits and vegetables by liquid chromatography-mass spectrometry after ethyl acetate multiresidue extraction. , 2000, Journal of AOAC International.