Glycohemoglobin quantitation by alkaline gel electrophoresis. A reliable technique with practical clinical advantages

The Beckman Paragon alkaline gel electrophoresis system was evaluated for utility in identification and quantitation of glycosylated hemoglobin in the clinical laboratory setting. In contrast to other alkaline hemoglobin electrophoresis systems, this system provides adequate separation of HbA0 from its glycosylated form. A band anodal to HbA0 was identified as glycohemoglobin; in vitro synthesis of glycohemoglobin confirmed the migration pattern of the glycohemoglobin band. In both in vitro synthesis studies and in a series of 48 patients, quantitation of the glycohemoglobin band by densitometry showed good correlation (r = 0.99 and r = 0.96, respectively) with values obtained by a standard column chromatographic technique. Beyond reliable quantitation of glycohemoglobin, this system offers two advantages. First, it discriminates hemoglobin F and hemoglobins with low isoelectric points that may coincidentally be measured as glycohemoglobin by other techniques. Second, it provides simultaneous detection of common hemoglobinopathies, a necessity for accurate reporting of glycohemoglobin in the diabetic patient with a concomitant hemoglobinopathy.