Bromocresol green spray

Citric acid water n-butanol 4.8 g 103 ml 870 ml. Ultraviolet, iodoplatinate spray (strong reaction), bromocresol green spray (strong reaction) (0.19). 

The p-lactone is readily visualized by TLC (Merck, Kieselgel 60 F254, 0.25-mm thickness, hexane/ethyl acetate (55/45) as solvent system) under UV, or by using bromocresol green spray (0.04% in EtOH, made blue by NaOH) followed by heating of the plate to detect the p-lactone as a yellow spot on a blue background. 

Visualization Technique A Ultraviolet Light B Potassium lodoplatinate Reagent C Bromocresol Green Spray... 

Apply separately to the plate 2.0 pL of each solution, and develop over a path of 15 cm using a mixture of equal volumes of ether and methylene chloride. Allow the plate to dry in air and spray with bromocresol green solution. The principal spot in... 

The identity of methanesulphonic acid may be determined by tic on cellulose plates, Merck no. 5728, with ethanol/ water/conc. ammonia 80 16 4 (v/v/v) as a mobile phase. Detection is achieved by spraying with acid-base indicators, e.g. bromocresol green or similar species. Rf of methanesulphonic acid is 0.5 (that of bromocriptine base = 0.9). 

Spraying with a 0.01-1% aqueous or aqueous alcohol solution of an acid-base indicator (e.g., bromocresol green, bromothymol blue, bromophenol blue, methyl red, malachite green) can detect acid or basic compounds on the layer based on a change in color at the location of the zones and knowledge of the pH transition range of the indicator. 

Cephalosporin C, 7-ACA and related compounds converted to N-phenylacetyl derivatives by spraying dried chromatogram with pyridine in 50% acetone (v/v) until barely damp. Then, lightly spray with 2% (w/v) phenylacetyl chloride in acetone, and again with the pyridine solution until a spot of bromocresol green placed on the paper immediately turns blue (pH 5.0). Dry in air 3-5 min and bioautograph vs. Staphylococcus aureus (Oxford strain N.C.T.C. 6571)... 

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