Journal of Chromatography A, 1153 (2007) 114–129 Review Current perspectives in analyte extraction strategies for tin and arsenic speciation Christian Dietz, Jon Sanz, Estrella Sanz, Rian Mu ˜ noz-Olivas, Carmen C´ amara ∗ Department of Analytical Chemistry, Faculty of Chemistry, University Complutense de Madrid, Ciudad Universitaria, 28040 Madrid, Spain Available online 8 December 2006 Abstract 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 modern analytical method development and can be judged as the “Achilles’ heel” of any analytical process regarding reliabil- ity of the obtained results and time consumption. The aim of the present review is to highlight modern trends for tin and arsenic speciation, as these analytes can be considered as models for challenges in modern method development in this field. First background information, leg- islative 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 modern 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. © 2006 Elsevier B.V. All rights reserved. Keywords: Arsenic; Tin; Speciation; Extraction Contents 1. Introduction ............................................................................................................ 115 2. Sample treatment and speciation analysis .................................................................................. 116 3. Sample preparation ...................................................................................................... 116 4. Extraction techniques .................................................................................................... 117 4.1. Solvent extraction ................................................................................................. 121 4.2. Enzymatic hydrolysis ............................................................................................. 122 4.3. Solid phase extraction ............................................................................................. 122 4.4. Molecularly imprinted solid-phase extraction ........................................................................ 122 4.5. Solid phase microextraction ........................................................................................ 123 4.6. Pressurised liquid extraction ....................................................................................... 124 4.7. Microwave assisted extraction ...................................................................................... 124 4.8. Ultrasound probe sonication ....................................................................................... 125 4.9. Supercritical fluid extraction ....................................................................................... 126 5. Conclusions ............................................................................................................ 126 Acknowledgements ..................................................................................................... 127 References ............................................................................................................. 127 ∗ Corresponding author. Tel.: +34 91 394 4318; fax: +34 91 394 4329. E-mail address: ccamara@quim.ucm.es (C. C´ amara). 0021-9673/$ – see front matter © 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.chroma.2006.11.064