Comparison of Sebia Capillarys Flex capillary electrophoresis with the BioRad Variant II high pressure liquid chromatography in the evaluation of hemoglobinopathies.

Background: There are multiple biochemical screening techniques for assessing hemoglobinopathies. Here we compare a new instrument, the Sebia Capillarys Flex (capillary zone electrophoresis (CE)), with the BioRad Variant II (high pressure liquid chromatography (HPLC) in the evaluation of hemoglobinopathies.

Methods: This was a retrospective study using 174 whole blood samples encompassing the 5 most common (Hb A, A2', S, C, and E) and 10 rare (Hb G(Philidelphia), D, H, Bart's, O(Arab), S/G(Philidelphia), Hasharoon, Q(India), N(Baltimore), and Malmo) hemoglobin variants. An additional 126 samples were used to establish a CE reference interval for Hb A2.

Results: Hb A measurements agreed well between the 2 methods (bias=-0.06;r=0.999). The agreement of Hb F was also very good (bias=-0.17; r=0.994). When samples with the highest Hb F concentration were excluded, agreement was less precise (bias=-0.44; r=0.811). When no variant was present, the Hb A2 concentrations showed excellent agreement (bias=0.00; r=0.994). Positive bias for Hb A2 is seen when Hb C is present using CE. The Hb A2 reference interval using CE was <3.2%.

Conclusion: The Capillarys Flex is capable of identifying and quantifying hemoglobin species, consistent with existing HPLC methods.