ABSTRACT

Determination of the chemical composition of complex environmental samples is a challenging task, owing to myriad species of compounds, many of them present in only trace amounts. Typically, chromatographic techniques are utilized in the analysis of complex environmental samples. However, most samples cannot be injected directly into the chromatographic system without sample preparation. It is worth stressing that the sample preparation step required before the chromatographic separation largely determines the quality of obtained results. The sample preparation procedure also signicantly impacts assay throughput, data quality, and analysis

8.1 Introduction .................................................................................................. 329 8.2 Sample Preparation Techniques.................................................................... 331

8.2.1 Drying and Homogenization of Solid Samples ................................ 333 8.2.2 Extraction .......................................................................................... 333

8.2.2.1 Vapor-Phase Extraction ...................................................... 334 8.2.2.2 Liquid Samples .................................................................. 335 8.2.2.3 Solid and Semisolid Samples .............................................344