Improvement in measurement precision with SPME by use of isotope dilution mass spectrometry and its application to the determination of tributyltin in sediment using SPME GC-ICP-MS

摘要: A method is described for the accurate and precise determination of tributyltin (TBT) by species specific isotope dilution mass spectrometry (ID-MS) using solid phase microextraction (SPME) in combination with gas chromatographic (GC) separation inductively coupled plasma spectrometric (ICP-MS) detection. Butyltin compounds were ethylated aqueous solution sodium tetraethylborate headspace sampled a polydimethylsiloxane coated fused silica SPME fiber. The analyte was then directly transferred from fiber to head GC column desorption following insertion through heated injection port. Reverse spike ID analysis performed determine concentration 117Sn-enriched TBT two well characterized natural abundance standards. 0.923 ± 0.005 µg g−1 (one standard deviation, n = 5) as tin obtained National Research Council Canada (NRCC) marine sediment PACS-2 present method, good agreement certified value 0.98 0.13 g−1 (as 95% confidence interval). 0.93 0.09 n = 5) subsequently determined additions calibration tripropyltin (TPrT) an internal standard. An eighteen-fold improvement precision measured observed, clearly demonstrating its superiority providing more results compared additions. detection limit (3s) ng g−1 estimated sediment.