The automatic TLC sampler 4 (ATS 4) from Camag, Fig. 4, is anexample of a fully programmable automated sample applicator thatcan apply samples as spots (0.1–5 L) by contact transfer or asbands or rectangles by the spray-on technique (samples >0.5 L).Samples are housed in a vial rack (66 sample vials) or 96-wellplate and can be selected in any order for application to the layer.Samples scan also be applied in sequence as an overlay of sam-ple and standard (standard additions). The syringe is automatically emptied and rinsed between sample applications. A heated spraynozzle (at 60◦C) is available to facilitate the application of aque-ous samples (and similar moderate volatility solvents). A recentupgrade (ATS4 FREE MODE) was introduced for the applicationof reagents to diagnostic strips with different shapes and for theprogrammed application of samples to multiple plates.