Preparation and control of ethylene glycol-stabilized haemolysates for glycated haemoglobin assay

The preparation and evaluation of ethylene glycol-stabilized haemolysates for use as control material for the assay of glycated haemoglobins is described. These haemolysates were prepared from normal and diabetic blood samples by following the procedure normally used to purify human haemoglobin, with the addition of dialysis to remove glucose from the labile fractions, and dilution with ethylene glycol. All the haemoglobin fractions were converted into the carbon monoxide form to increase their stability and were stored under different conditions. During a 10 month period of storage at -20 degrees C no significant change in the glycated haemoglobins level was observed.