Performance evaluation of immunoturbidimetry in determining glycosylated hemoglobin A1c

Objective To evaluate the performance of immunoturbidimetry in determining glycosylated hemoglobin(HbA1c).Methods The precision and linearity of immunoturbidimetry in determining HbA1c were analyzed,and the effects of hemoglobin(Hb),fetus Hb(HbF),triacylglycerol(TG),total bilirubin(T-Bil) and instable HbA1c on the determination of HbA1c were evaluated.The correlation and consistency of HbA1c results determined with immunoturbidimetry and high performance liquid chromatography(HPLC) were also analyzed.Results The coefficient of variance(CV) of HbA1c results determined with immunoturbidimetry was below 2.5%.There was a good linear correlation(r2 =0.999) between the theoretical value and actual results of HbA1c in a range of 4.7% to 15.4%.The deviations of HbA1c results were all below 5% when the levels of Hb,HbF,T-Bil and TG were in the ranges of 57 to 177 g/L,1.7% to 11.7%,27 to 265 μmol/L and 3.2 to 9.85 mmol/L,respevtively.When the concentration of HbF was above 13.5%,the deviation of HbA1c results was above 5%.The instable HbA1c(glucose concentration between 0 and 55.56 mmol/L) did not show obvious effect on the determination of HbA1c.There was a good correlation between the results of immunoturbidimetry and HPLC(Y=1.018 8X-0.227 1,r2=0.971 3).Conclusion HbA1c level was effectively determined by immunoturbidimetry method which should be suitable for clinical application.