An inexpensive, rapid and precise affinity chromatography method for the measurement of glycosylated haemoglobins

We have assessed an affinity chromatography technique, using commercially available materials, for the estimation of total glycosylated haemoglobin in the routine clinical chemistry laboratory. The method gives good discrimination between normals (7.31 +/- 0.92%) and diabetics (12.70 +/- 2.88%) and has excellent precision (CV 1.5-2.0%). Labile glycosylated haemoglobin is normally removed as it is so variable. There is no significant correlation between labile glycosylated haemoglobin and blood glucose. Immediate analysis of incubated haemolysates is preferable to storage of haemolysates or erythrocytes. The affinity gel can be reused about 16 times, but oxidation must be reduced by keeping the gel at 4 degrees C in the dark when not in use. The cost of the gel is about 7p a test and 60 samples can be analysed in a working day. The method is not affected by the presence of up to 20% met-haemoglobin and should also give correct values for samples containing genetic variants of haemoglobin.