Trace determination of organotin compounds in water, sediment and mussel samples by low-pressure gas chromatography coupled to tandem mass spectrometry.
A fast method for the determination of eight organotin compounds (OTs), monobutyltin (MBT), dibutyltin (DBT), tributyltin (TBT), tetrabutyltin (TeBT), monophenyltin (MPhT), diphenyltin (DPhT), triphenyltin (TPhT) and tetraphenyltin (TePhT), in water, sediments and mussels, was developed using low-pressure gas chromatography/tandem mass spectrometry (LPGC/MS/MS). The method is based on sodium diethyldithiocarbamate (DDTC) complexation of the ionic organotins, followed by extraction of the target matrices and derivatization by a Grignard reagent, as described in a previously published method for water samples. Solid-phase extraction was selected as extraction method from water samples after comparison with liquid-liquid extraction, but extraction of the OTs from sediment and mussel samples was performed using toluene. Matrix-matched calibration standards were used to minimize matrix effects. The analytical process was validated by the analysis of spiked blank samples. Performance characteristics such as linearity, detection limit (LOD), quantitation limit (LOQ), precision, and recovery were determined. Recoveries of OTs in spiked matrices ranged from 86-108% in water and from 78-110% in sediments and mussels, with precision values lower than 18%. Detection limits ranged from 0.1-9.6 ng L(-1) in water, and 0.03-6.10 microg kg(-1) in the other matrices. The present implementation of LPGC rather than conventional capillary GC permitted use of large-volume injection and reduced analysis time by a factor of two. The proposed methodology was applied to the determination of OTs in real samples of water, marine sediments and mussels from the west coast of the Mediterranean Sea (Spain).
Vidal
J L Martínez
JL
Department of Analytical Chemistry, University of Almería, 04120 Almería, Spain. jlmartin@ual.es
Vega
A Belmonte
AB
Arrebola
F J
FJ
González-Rodríguez
M J
MJ
Sánchez
M C Morales
MC
Frenich
A Garrido
AG
D000818:Animals; D049872:Bivalvia / Q000737:chemistry*; D002138:Calibration; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D019015:Geologic Sediments / Q000737:chemistry*; D015394:Molecular Structure; D009930:Organic Chemicals / Q000032:analysis*; D011312:Pressure; D015203:Reproducibility of Results; D012623:Seawater / Q000737:chemistry*; D017971:Tin Compounds / Q000032:analysis*
D009930:Organic Chemicals; D017971:Tin Compounds