The relation between the results of determination of fructosamine and glycosylated proteins of blood serum.

Fructosamine concentration (measured by NBT reduction method) and the concentration of glycosylated proteins (measured by a direct UV spectrophotometry upon separation from nonglycosylated proteins by means of affinity chromatography, have been determined simultaneously in 52 samples of blood serum obtained from 42 children with diabetes mellitus and 10 children without metabolic disorders. A highly significant positive correlation (r = 0.96, p < 0.001) was found between the two parameters. It was concluded that fructosamine determination by NBT reduction test reflects the true concentration of glycosylated proteins of blood serum, provided that the proper correction factor derived from the equation of linear regression is used as shown in the following equation: Concentration of glycosylated proteins of blood serum in milligram = 2.78 x (fructosamine concentration in mmol/l + 1.26).