title: Determination of haemoglobin A1c by iso-electric focusing. Effect of incubation of erythrocytes and comparison of results obtained by ion-exchange chromatography.
abstract: Blood samples from 24 non-diabetics and 26 diabetics were analysed using both thin layer iso-electric focusing and ion-exchange chromatography. Using isoelectric focusing it was found that about 10% of haemoglobin A1c (0.7-1.2% of total haemoglobin) could be removed by a preceding incubation of the erythrocytes in saline at 37 degrees C for 6 h. When glucose was added to the incubation medium in a final concentration of 25 mmol/l no decline was seen in the concentration of haemoglobin A1c. Using similar treatment of erythrocytes identical results were obtained by the two methods. A reference interval for normal subjects (age range 6 months to 65 years) was established for the iso-electric focusing method using non-incubated samples.
mesh_terms: D002852:Chromatography, Ion Exchange / Q000379:methods; D003920:Diabetes Mellitus / Q000097:blood; D004912:Erythrocytes / Q000032:analysis*; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D007525:Isoelectric Focusing / Q000379:methods
chemical_list: D006442:Glycated Hemoglobin