Current perspectives in analyte extraction strategies for tin and arsenic speciation

Nowadays, reliable and robust detectors can be considered standard laboratory instrumentation, which, for most of the elements provide quantitation limits in the lower ng/g range. Despite these advances in detector technology, sample preparation is by far the most important error source in modem analytical method development and can be judged as the Achilles' heel of any analytical process regarding reliability of the obtained results and time consumption. The aim of the present review is to highlight modem trends for tin and arsenic speciation, as these analytes can be considered as models for challenges in modem method development in this field. First background information, legislative aspects and current needs are elucidated. Then the role of sample treatment within the process of method development in speciation is discussed, followed by a presentation of modem extraction techniques, matching the requirements for arsenic and tin speciation analysis: to provide mild conditions in order to ensure species preservation, to improve species recovery, to enhance sample throughput and to be suitable for hyphenation with chromatographic separation systems. The review includes applications on tin and arsenic speciation, covering the period of 2001-2006. (c) 2006 Elsevier B.V. All rights reserved.