[A study of the o-toluidine method for glycogen measurement (author's transl)]

The application of the o-toluidine procedure for glucose estimation was studied in the determination of glycogen. Decrease in final colour formation, caused by the acid used on hydrolising glycogen, was the major problem. 90 minutes incubation periods with 1N sulphuric acid at 100 degrees C, produced best results. Some other steps of this method and their application to glycogen measurement are also discussed. The proposed procedure leads to a stable colour formation, proportional to glycogen concentration, and allows determination of polysaccharide in small biological samples.