Determination of haemoglobin A1c by liquid chromatography using a new cation-exchange column

The use of a new cation-exchange column, ProPac SCX-10, for the determination of haemoglobin A1c (HbA1c) by high-performance liquid chromatography is described. After optimization of the analytical method for the separation of the various isoforms of haemoglobin with the ProPac SCX-10 column, the method was applied to the determination of HbA1c in blood from 59 volunteers. Three of the 59 had previously been diagnosed as diabetics. Interference studies for carbamylation, acetylation and pre-HbA1c were carried out via “in-vitro” experiments. No interference due to carbamylation was observed at the urea values normally found in uremic patients undergoing dialysis. No interference from pre-HbA1c was detected either. The method is able to separate haemoglobin A (α2β2), haemoglobin S (haemoglobin from sickle cell anaemia patients) and haemoglobin A2 (α2δ2) without interference. The method of Hampel was applied to detect outliers. A value of 3.29±0.44% (2σ) for HbA1c was obtained in the analysis of 56 blood samples from non-diabetics. This average value is lower than that reported by most of the methods currently used in routine analyses.