Preparation method of phosphomolybdic acid (PMA) developer
10 g Phosphomolybdic acid + 100 mL B reverse osmosis fungicide alcohol
Light yellow, it will turn into light green after being left for a long time, which does not affect its use. Dip plate or spray plate, heat, light yellow background, reducing substances will show blue-green spots, if the spots are too thick, they may appear dark yellow.
Scope of application
Suitable for compounds containing conjugated groups and aromatic compounds.
1. Color reaction for proteins (Folin reaction): It is the reaction of the phenolic group of Tyr with phosphomolybdic acid and phosphotungstic acid, which turns blue. This reaction is mainly used for quantitative analysis of proteins.
2. Used for some non-characteristic physical and chemical identification of lignans: 5% phosphomolybdic acid ethanol solution (105 degrees, 2-3min) can be used for thin layer chromatography color development.
3. Precipitation reaction of alkaloids: Phosphomolybdic acid diluent reagent reacts with alkaloids to form white or light yellow precipitate.
4. Can react with triterpenoids such as oleanolic acid: The method is to spray phosphomolybdic acid ethanol solution (100 degrees, 5 minutes) to develop color, then heat it at 120°C for a few minutes.
5. Color reaction of flavonoids: dihydroflavones can react with phosphomolybdic acid reagent to produce a brown color, which can be used as a characteristic identification reaction of dihydroflavones.
