Samples Adsorbed on Thin Layers

Particularly for microanalytical investigations, it is favorable to adsorb 1 to 10 pL of liquid or a few milligrams of a material dissolved in the same volume of water or another suitable solvent on thin-layers (0.2 mm) of alumina or silica stabilized on sheets of polystyrene, polyethylene, or aluminum [35]. 

Of course, developed spots of TLC can also be analyzed in the same manner [30]. The entire TLC sheets or cut-out spots are fixed between two silica plates one of these plates has a cavity 0.2 mm deep to take up the sample. In Fig. 4-45 the powerful resolution of a spectrum of a TLC spot by HODS is clearly visible. 

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