Lab Med Online.  2013 Oct;3(4):221-226.

Performance Evaluation of the CAPILLARYS 2 FLEX Piercing Analyzer for HbA1c Determination

• Jeon Y
• Han M
• Lee K
• Chang HE
• Park KU
• Song J

Abstract

BACKGROUND
The hemoglobin A1c (HbA1c) level is widely used to monitor glycemic control in diabetes mellitus patients, and various methods are used for its determination. The CAPILLARYS 2 FLEX Piercing (Sebia) is a fully automated, high-throughput glycohemoglobin (HbA1c) analyzer based on capillary electrophoresis.
METHODS
The analytical performance of the CAPILLARYS 2 FLEX Piercing analyzer was evaluated for its precision, linearity, correlation with the Variant II Turbo (Bio-Rad Laboratories, Inc.) analyzer, and its vulnerability to interference by carbamylated hemoglobin. We also investigated its agreement with National Glycohemoglobin Standardization Program (NGSP) targets. All evaluations were performed according to CLSI guidelines EP05, EP06, and EP09.
RESULTS
The coefficients of variation (CVs) for within-run and total imprecision were 1.7% and 1.8% at low concentrations and 1.2% and 1.3% at high concentrations, respectively. Linearity was excellent, with R2=0.9882 in the range of 5.13-13.83%; these results highly correlated with those produced by Variant II Turbo (R2=0.9978). The 95% confidence interval (for differences from the NGSP target) was -0.3618-0.3343%. No significant interference of carbamylated hemoglobin was noted.
CONCLUSIONS
The CAPILLARYS 2 FLEX Piercing analyzer showed excellent precision and linearity. Its results correlated with those obtained by the Variant II Turbo analyzer, and were agreement with the NGSP target. Therefore, its analytical performance is satisfactory for diabetes diagnosis and treatment monitoring.

Keyword

Hemoglobin A1c (HbA1c); Capillary electrophoresis; Diabetes

MeSH Terms

Capillaries
Diabetes Mellitus
Electrophoresis, Capillary
Hemoglobins
Humans
Organothiophosphorus Compounds
Hemoglobins
Organothiophosphorus Compounds

Figure

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  Fig. 1 Linearity of HbA1c values using the CAPILLARYS 2 FLEX Piercing analyzer.

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  Fig. 2 Comparison of HbA1c levels measured using the Variant II Turbo analyzer (comparative) and the CAPILLARYS 2 FLEX Piercing analyzer (test).

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  Fig. 3 Relationship between serum urea concentrations and the absolute difference in HbA1c percentages obtained using the 2 methods.

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  Fig. 4 Assessment of agreement of HbA1c levels between the NGSP target and CAPILLARYS 2 FLEX Piercing analyzer.

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