It is formed by non-enzymatically attachment of glucose to different amino groups of both 2 alpha and 2 beta chains of normal adult hemoglobin A (HbA). The relative amount of glucose bond to the N-terminal of the beta chain is measured as HbA1c. HbA1c is used to monitor long-term glycaemic control and treatment of diabetes.
Assessment of long-term glycemic control in diabetics.
Matrix: Whole blood.
Volume: Minimum volume is 20 µL, but 100 µL is optimal and allows reanalysis.
Preparation and stability: The blood sample must be put on ice, and frozen. HbA1c is stable for one week at 4-8C. At -70 °C, HbA1c is stable for many years and slightly increases if stored for more than one decade.
Reference values: 4-6%.
In diabetes patients values can range from 6.5 up to 14%.
Intraclass correlation coefficient (ICC): na.
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