Determination of glucitollysine for the quantitation of non-enzymatic glucosylation by ion exchange chromatography and reverse phase liquid chromatography

Abstract A specific and sensitive method for the quantitative determination of the stable, reduced glucose-lysine adduct, glucitollysine (GL), in plasma protein samples is described. The method uses standard amino acid ion exchange chromatography followed by reverse phase high performance liquid chromatography after derivatisation of GL to a fluorescent product. Moreover, GL was characterised and identified in plasma samples by means of mass spectroscopy. GL measured in plasma samples of eleven type I diabetics and two healthy controls showed a significant linear correlation to concomitantly determined haemoglobin A 1 and glucosylated plasma proteins, but did not correlate with plasma glucose levels. This method allows the estimation of non-enzymatic glucosylation in biological samples with a high degree of specificity and sensitivity down to the low nanogram range.