A Comparative Evaluation of Capillary Electrophoresis, Cation-Exchange High-Performance Liquid Chromatography, and Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry for the Screening of Hemoglobin Variants

Objectives: The present study was conducted to evaluate the usefulness of capillary electrophoresis (CE), cation-exchange high-performance liquid chromatography (HPLC), and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) for the screening of hemoglobin (Hb) variants prevalent in southern China. Methods: A total of 102 types of Hb variants in 1,083 variant carriers were identified over a 5-year period. These variants were analyzed by a CE method (Capillarys 3 TERA), a cation-exchange HPLC analyzer (Variant II Turbo 2.0), and a MALDI-TOF MS system (QuanTOF). Results: The presence of 85 (83.3%, 85/102), 84 (82.4%, 84/102), and 62 (60.8%, 62/102) Hb variants was detected by Capillarys 3 TERA, Variant II Turbo 2.0, and QuanTOF, respectively. Of the three methods, only Capillarys 3 TERA recognized all 10 of the most frequent Hb variants in southern China. There were six, two, and three Hb variants that can only be detected by Capillarys 3 TERA, Variant II Turbo 2.0, and QuanTOF, respectively. The detection limit of mass difference for QuanTOF was approximately 11 to 20 Da. Conclusions: MALDI-TOF MS is suitable for use as an auxiliary method rather than a stand-alone method for the screening of Hb variants prevalent in southern China.

Automated summary

Capillary electrophoresis (CE) showed the highest accuracy in screening for Hb variants in southern China, detecting all of the top ten common variants. MALDI-TOF MS is suitable for use as an auxiliary method rather than a stand-alone method.