Glucose-6-phosphate Assay

Glucose-6-phosphate (G6P) is the first substrate in glycolysis, the hexose monophosphate shunt and both the glycogen and starch biosynthesis pathways. G6P is utilized by glucose-6-phosphate dehydrogenase to generate reducing equivalents in the form of NAD(P)H. This is particularly important in red blood cells where a G6PDH deficiency leads to hemolytic anemia. This colorimetric assay is based on glucose-6-phosphate dehydrogenase catalyzed oxidation of G6P, in which the formed NADPH can convert a nearly colorless probe to an intensely colored product, which exhibits maximum absorbance at 440nm, is proportional to the amount of G6P in the sample.