Evaluation of MALDI-TOF MS for the measurement of glycated hemoglobin

Abstract

BackgroundGlycated hemoglobin (Hemoglobin A1c, HbA1c) plays a key role in monitoring long-term blood glucose levels in diabetics mellitus. Therefore, it is of great importance to ensure test quality of HbA1c methods. ObjectivesWe aimed to evaluate analytical performances of a matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) system for the measurement of HbA1c. MethodsWe assessed the analytical performances of the method including imprecision, accuracy, and linearity. In addition, comparison with Variant II Turbo 2.0 and Capillarys3 TERA, correlation between glycation rate of α and β globin as well as the influence of most frequent analytical interferences in HbA1c assays were also investigated. ResultsAs measurement of imprecision, within-run CVs and total CVs were lower than 1.6% and 2.4%, respectively. Discrepancy of test results (<0.2%) of IFCC value-assigned external quality control samples indicated a good accuracy of the method. The linearity was excellent with a correlation coefficient of 0.999. The QuanTOF results were well correlated with those obtained by Variant II Turbo 2.0 and Capillarys3 TERA. Good correlation between glycation rates of α and β globin were found. QuanTOF was not prone to common interferences including bilirubin, triglyceride, labile A1c, and carbamylated hemoglobin. However, unacceptable positive bias was observed when the amount of HbF were greater than approximately 8.0% or in the presence of HbS. ConclusionsQuanTOF perform well for the determination of HbA1c and meet quality criteria requested for clinical use.