Effect of HbS in the determination of HbA2 with the TOSOH HLC-723G7 analyzer and the HELENA Beta-Thal Quik column kit

Objectives: The analytical performance of the TOSOH HLC-723G7 hemoglobin HPLC analyzer and the effect of the presence of HbS in the determination of HbA2 using HPLC and manual column methods. Design and methods: The performance characteristics of the TOSOH HLC-723G7 analyzer in the determination of HbA2 were compared to those of the HELENA Beta-Thal Quik column. The effect of HbS presence in the samples was quantified using the HELENA SAS-MX alkaline gel electrophoresis kit as the reference method. Results: Within-run and between-run CVs for HbA2 were better for the TOSOH HPLC analyzer than for the HELENA manual column method. The presence of HbS in the samples produces a strong positive bias in the %HbA2 values when using both the HPLC and manual column methods, compared to the alkaline electrophoresis gel. Conclusion: Both the TOSOH HPLC and the manual column are reliable methods for %HbA2 determination when no HbS is detectable in the samples. When HbS is present, the gel electrophoresis method gives more accurate results.