Chambers saturation

Fig. 57 Schematic representation of the relationships between development, chamber saturation and pre-loading with solvent vapors (ace. [8]).

But there can be no question of chamber saturation if the TLC plate is then placed directly in the chamber. But at least there is a reduction in the evaporation of mobile phase components from the layer. Mobile phase components are simultaneously transported onto the layer (Fig. 57). In the case of multicomponent mobile phases this reduces the formation of / -fronts. 

The description of the experiment must, therefore, state what type of chamber was used and whether "chamber saturation" was employed. 

One-dimensional ascending development in a HPTLC chamber with chamber saturation. 

Ascending, one-dimensional development in a trough chamber without chamber saturation. 

A) Ascending, one-dimensional, double development in a trough chamber (5 min drying in warm air between developments) with chamber saturation. 

Ascending, one-dimensional development in a twin-trough chamber with chamber saturation with the layer being preconditioned in the solvent-free half of the trough for 15 min after application of the sample. 

Ascending, one-dimensional development at 10 —12 °C in a twin-trough chamber with 5 ml cone, ammonia solution in the trough containing no mobile phase (chamber saturation 15 min). 

Ascending, one-dimensional multiple development method (stepwise technique, drying between each run) in two mobile phase systems in a twin-trough chamber without chamber saturation (equilibration 30 min at 20-22°C) at a relative humidity of 60 — 70%. 

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