ENZYME-IMMUNOASSAY - A NEW TECHNIQUE FOR ESTIMATING HEMOGLOBIN A1C

We describe a method for estimating hemoglobin A1c (HbA1c) with a comm ercially available enzyme immunoassay system. The method is based on m icrotiter plate technology, utilizing an antibody raised to hemoglobin , the epitope being the Amadori product of glucose plus the first eigh t amino acids on the N-terminal end of the beta chain of hemoglobin. T he enzyme immunoassay displays good within-batch (CV 2.3-2.4%) and bet ween-batch (CV 2.6-5.0%) precision, and the results were not affected by different types of anticoagulant. The method was linear within the expected range of results and showed good correlation (r = 0.88-0.98) with established methods for estimating glycohemoglobin. Using this me thod, we obtained a reference interval of 2.8-4.9% (central 95%) for H bA1c in a nondiabetic population. The percentages of hemoglobin that w ere HbA1c in diabetics (6.86% +/- 2.51%) were significantly greater (P <0.001) than in nondiabetics (3.46% +/- 0.52%).