ABSTRACT
BACKGROUND: Hemoglobin A1c (HbA1c) is a useful marker for the diagnosis and monitoring of diabetes, which has resulted in an increasing dependency on HbA1c levels for diagnosing diabetes in small- and medium-sized hospitals. We evaluated a high performance liquid chromatography (HPLC) based HbA1c autoanalyzer Bio-Rad D-10 (Bio-Rad Laboratories, USA) by comparing the analysis results with that by Tosoh HLC-723 G7 (Tosoh Corporation, Japan). METHODS: The Bio-Rad D-10 autoanalyzer was evaluated for its precision, linearity, and carryover. The analysis time and correlation were evaluated and compared with those by Tosoh HLC-723 G7 autoanalyzer. RESULTS: Bio-Rad D-10 showed within-run, between-day, and total precision of less than 1.3% coefficient of variation (CV) and excellent linearity between HbA1c in the range of 3.2%-21% (coefficient of determination, R 2 = 0.998). The sampleto-sample carryover was 0.57%. The results obtained by using Bio-Rad D-10 showed good correlation (r = 0.997; P < 0.001) with those by Tosoh HLC-723 G7; however, the analysis time using Bio-Rad D-10 was about 2.3 times per 10 samples and 2.5 times per 20 samples than those using Tosoh HLC-723 G7. CONCLUSIONS: Bio-Rad D-10 showed good performance in assaying HbA1c. Bio-Rad D-10 autoanalyzer would be suitable for use in laboratories with small to medium amount of samples to be analyzed, but its initial analyzing time was longer than that by Tosoh HLC-723 G7.
Subject(s)
Chromatography, Liquid , Dependency, Psychological , HemoglobinsABSTRACT
BACKGROUND: We evaluated the performance and analysis time of HLC-723 G7 (Tosoh corp. Tokyo, Japan) hemoglobin (Hb) A1c autoanalyzer. It utilizes cation exchange high performance liquid chromatography (HPLC) method and has a reduced analysis time compared with that of an earlier model HLC-723GHb V A1c 2.2(TM) (HLC-723GHb V, Tosoh corp. Tokyo, Japan). METHODS: We evaluated linearity, precision and comparison with HLC-723GHb V following NCCLS guidelines and counted the number of tests per hour to estimate analysis time. RESULTS: Linearity through the range from 5.8% to 13.9% was good (r2=0.9930, relative nonlinearity <2.5%). The within-run coefficients of variation (CVs) for groups of low, middle, and high level were 1.09%, 0.76%, and 0.68% and total CVs for each group were 1.60%, 0.91%, and 1.00%, respectively. Correlation equation between HLC-723 G7 and HLC-723GHb V was HLC-723 G7=1.0308 (HLC-723GHb V)-0.2896 %Hb A1c (r=0.9992, P<0.0001). Analysis time of HLC-723 G7 was 1.2 minutes per test compared with 2.1 minutes of HLC-723GHb V. CONCLUSIONS: HLC-723 G7 showed the acceptable performance and shortening analysis time therefore, it was suitable for reducing turn around time of Hb A1c assay.
Subject(s)
Chromatography, Liquid , Glycated HemoglobinABSTRACT
BACKGROUND: Hemoglobin A1c (HbA1c) is widely used for the monitoring of glycemic control. A wide variety of different analytical methods is currently used by clinical laboratories. We performed this study to evaluate the newest ion-exchange high-performance liquid chromatography system, the HLC-723 G7 (Tosoh Corporation, Tokyo, Japan) automated glycohemoglobin analyzer. METHODS: HLC-723 G7 was evaluated for linearity, precision, comparison of method, and speed. HLC-723 G7 was compared with three analyzers including HLC-723 GHb V A1c 2.2, Variant II, and Cobas Integra 800. RESULTS: HLC-723 G7 showed within-run and total imprecision (CVs) of less than 2.5% and excellent linearity to at least 13.0%. HbA1c values obtained from HLC-723 G7 were strongly correlated with those from HLC-723 GHb V A1c 2.2. Comparison with two other methods showed a good correlation but revealed calibration differences throughout the analytical range. HLC-723 G7 required no sample preparation and showed a fast analytical time of 1.6 min. CONCLUSIONS: HLC-723 G7 provides high throughput and excellent precision. However, HbA1c values can differ considerably with different methods or instruments. Therefore, we should be aware of the potential problem in switching the HbA1c testing method
