Drying the Chromatogram

For these reasons many research groups prefer to dry the chromatograms in a vacuum desiccator with protection from light. Depending on the mobile phase employed phosphorus pentoxide, potassium hydroxide pellets or sulfuric acid can be placed on the base of the desiccator, to absorb traces of water, acid or base present in the mobile phase. 

Dry the chromatogram in a stream of warm air and immerse for 2 — 3 s in the reagent solution or spray the layer with it until this acquires an even yellow coloration and dry in a stream of warm air (ca. 2 min). 

Colored or, under long-wavelength UV light (X, = 365 nm), yellow or blue fluorescent chromatograph zones appear, even after drying the chromatogram in a stream of cold air, but sometimes only after heating to 80 °C [17], to 130 C [9] or 150 C [22] for 5-10 min. 

Identification of amino acids by chromatography. Use a 4 1 2 mixture of butanol, ethanoic acid and water as a solvent. Dry the chromatogram and develop with a ninhydrin spray. 

Hydroxylamine-ferric chloride A 1 2 mixture of a 10% hydroxylammonium chloride/10% potassium hydroxide in aqueous ethanol is sprayed on the plate followed by drying. The chromatogram is then sprayed with an ether solution of ferric chloride in hydrochloric acid to yield a variety of spots. 

Estrone, estradiol, estnol again into the reagent solution dry the chromatogram and develop it. Dip alica gel foil 2 cm in saturated Fast Black Salt K solution and dry in a stream of warm air. Apply [294]... 

Millee and Kiechnee [168] had also suggested activation of the adsorbent layer back in 1953. They achieved this by drying the chromatogram strips over phosphorus pentoxide in a vacuum desiccator at 3 mm mercury pressure. Since the danger of inactivation by air humidity is so great with the standard sizes used today and the standard 250 [i thicknesses, the procedure is of no more than historical interest. 

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