ABSTRACT
Prior to analyte determination by an instrumental analytical method, sample preparation is a crucial preliminary step that decisively affects the nal analytical result. However, its importance in the total analytical method is often underestimated relative to the instrumental measurement steps. Sample preparation is usually given limited or no coverage in books and review articles on thin layer chromatography (TLC), so this chapter is devoted lling the gap of comprehensive information on techniques that have been used to prepare the sample applied to the plate prior to its development with the mobile phase in order to achieve high-quality analytical results. Laboratory samples must be representative of the original material to which the analytical method is to be applied, and they must be transported and stored so as to not change their composition prior to analysis. Use of both traditional and newer sample preparation technologies is discussed in the following sections for selected applications of TLC and high-performance TLC (HPTLC) to a wide range of analyte and sample types reported in the literature. Throughout this chapter, TLC is often used as a term that covers analysis on both HP and non-HP plates.
