OPTIMIZATION OF SUPERCRITICAL FLUID EXTRACTION/HEADSPACE SOLID‐PHASE MICROEXTRACTION AND GAS CHROMATOGRAPHY–MASS SPECTROMETRY METHOD FOR DETERMINATING ORGANOTIN COMPOUNDS IN CLAM SAMPLES

Abstract

ABSTRACT For the food safety of sea products, the variables of headspace solid‐phase microextraction (HS‐SPME) and supercritical fluid extraction (SFE) were optimized for the determination of organotin compounds in clam samples by method of off‐line SFE/HS‐SPME and gas chromatographic analysis with mass spectrometry (GC‐MS). The best result was obtained while the spiked clam sample was extracted at 45C and 30 MPa with carbon dioxide modified with 5% (mol) methanol at 1.2 L/min (as carbon dioxide in ambient pressure) for 15 min, and SFE extract was ethylated with 2% (w/v) sodium tetraethylborate (NaBEt4) in pH 4 buffer solution and simultaneously adsorbed by HS‐SPME with polydimethylsiloxane‐divinylbenzene (PDMS/DVB) fiber at 50C for 30 min, followed by GC‐MS. The whole sampling and analyzing process was within 1 h, and only less than 10 mL of solvent were used. The results were comparable with those obtained by traditional method which use of methanol (contain 0.03% tropolone), and the procedure also seems to be less time‐ and labor‐consuming. The pollution of OTCs in seafood indicated a potential danger for the health of the local people who cared for these foods.PRACTICAL APPLICATIONSThe present investigation was carried out to optimize the method for the determination of organotin compounds in sea products. Organotin compounds (OTCs) was widely used in antifouling painting, which has been the most important pollution in marine environment. The sea products contaminated by the OTCs became a great problem on the food safety. Using this method for the determination of organotin compounds in sea products, the whole sampling and analyzing process was within 1 h, and only less than 10 mL of solvent were used. This method was a rapid and green method for monitoring the organotin pollution of sea products.