A REAGENT FOR QUALITATIVE USE
The property possessed by glucose, in common with many other sugars, of readily taking up oxygen in alkaline solution, is almost universally employed as a means of detecting this substance in urine.The glucose molecule itself, however, is not the active reducing substance in alkaline solution, it having been previously shown1 that the reducing action is due to a substance formed from the action of alkali on the sugar molecule. The reducing substance thus formed is not stable toward strong alkali, and unless permitted to exhibit its reducing action at once, is rapidly decomposed into compounds which have no reducing power, if sodium or potassium hydroxid be present. Solutions of the alkali carbonates, on the other hand, form the reducing substance from glucose a little more slowly than do the hydroxids, and have little, if any, deslniotive action on the reducing substance after it