Optimisation of the hyphenation between solid-phase microextraction, capillary gas chromatography and inductively coupled plasma atomic emission spectrometry for the routine speciation of organotin compounds in the environment

The hyphenation between solid-phase microextraction, gas chromatography and inductively coupled plasma atomic emission spectrometry (SPME-GC-ICP-AES) has been developed for the speciation of butyl- and phenyltin compounds in sediment and water samples. Factors determining the GC-ICP-AES analysis were optimised by an experimental design approach to evaluate critical parameters influencing the overall analytical performance system. Quasi-dry plasma conditions and a high helium carrier gas flow rate were required to obtain maximum performance in terms of sensitivity. The use of SPME to preconcentrate the analytes allowed detection limits within 1 to 42 ng (Sn) l(-1) to be obtained for water samples. Validation of the technique was performed by the analysis of certified reference sediment (PACS 2) and a wastewater sample.