Take D-Glucurone about 0.5g and add water for 5ml to dissolve, then test it according to the following method:
(1) Take 1 ml of solution, add 5 drops of toluene hydroquinone solution (0.1g and 10% ferric chloride solution, add hydrochloric acid to 100 ml, shake well, then get) 4 ml, heat in water bath for several minutes, the solution should be dark green, add 1 ml of pentanol after cooling, shake, green into pentanol layer.
(2) Take 1 ml of the solution, add 4 drops of 15% alpha-naphthol ethanol solution, shake well, slowly add along the wall of the tube containing concentrated sulfuric acid, so as to form two liquid layers, the interface is green, the upper water layer shows violet color, and the color becomes darker after placement.
Content determination
Take D-Glucurone about 0.5g, weigh it accurately, add new boiling water and cool it to below 20 ~C for 50 ml, dissolve it below 20 ~C, mix it up, add 3 drops of phenolphthalein indicator solution, titrate it immediately with hydrochloric acid titration solution (0.1mol/L), until red completely disappears, and the titration result is empty. White test correction. Sodium hydroxide titration solution per ml (0.1 mol/L) is equivalent to C6H8O6 of 17.61 mg.