Glycogen is a multibranched polysaccharide of glucose in α-1,4 linkage with branching via α-1,6 linkage and serves as a form of energy storage in animals. Glycogen is the main storage form of glucose in body and is mainly synthesized in the liver and muscle. Abnormal ability to utilize glycogen is found in several genetic glycogen storage diseases and diabetes. The Glycogen Colorimetric Assay Kit II provides a simple, fast and convenient way for detection of glycogen levels in various biological samples based on colorimetric method. In the assay, glycogen is hydrolyzed to glucose, which is oxidized to produce an intermediate that reduces a colorless Probe to a colored product with strong absorbance at 450 nm. The assay is suited for detection glycogen levels in samples that contain reducing substances, which may interfere with the oxidase-based assays The kit can detect less than 4 µg/mL of glycogen in samples and is suited for high-throughput assay.