Abstract | BACKGROUND: Glycated albumin is an intermediate glycaemic control marker for which there are several measurement procedures with entirely different reference intervals. We have developed a reference measurement procedure for the purpose of standardizing glycated albumin measurements. METHODS: The isotope dilution liquid chromatography/tandem mass spectrometry method was developed as a reference measurement procedure for glycated albumin. The stable isotopes of lysine and fructosyl-lysine, which serve as an internal standard, were added to albumin isolated from serum, followed by hydrogenation. After hydrolysis of albumin with hot hydrochloric acid, the liberated lysine and fructosyl-lysine were measured by liquid chromatography/tandem mass spectrometry, and their concentrations were determined from each isotope ratio. The reference materials (JCCRM611) for determining of glycated albumin were prepared from pooled patient blood samples. RESULTS: The isotope dilution-tandem mass spectrometry calibration curve of fructosyl-lysine and lysine showed good linearity (r = 0.999). The inter-assay and intra-assay coefficient of variation values of glycated albumin measurement were 1.2 and 1.4%, respectively. The glycated albumin values of serum in patients with diabetes assessed through the use of this method showed a good relationship with routine measurement procedures (r = 0.997). The relationship of glycated albumin values of the reference material (JCCRM611) between these two methods was the same as the relationship with the patient serum samples. CONCLUSION: The Committee on Diabetes Mellitus Indices of the Japan Society of Clinical Chemistry recommends the isotope dilution liquid chromatography/tandem mass spectrometry method as a reference measurement procedure, and JCCRM611 as a certified reference material for glycated albumin measurement. In addition, we recommend the traceability system for glycated albumin measurement.
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Authors | Izumi Takei, Tadao Hoshino, Makoto Tominaga, Midori Ishibashi, Katsuhiko Kuwa, Masao Umemoto, Wataru Tani, Mikiko Okahashi, Keiko Yasukawa, Takuji Kohzuma, Asako Sato |
Journal | Annals of clinical biochemistry
(Ann Clin Biochem)
Vol. 53
Issue Pt 1
Pg. 124-32
(Jan 2016)
ISSN: 1758-1001 [Electronic] England |
PMID | 26187553
(Publication Type: Journal Article)
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Copyright | © The Author(s) 2015. |
Chemical References |
- Glycation End Products, Advanced
- Serum Albumin
- Glycated Serum Albumin
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Topics |
- Blood Chemical Analysis
(standards)
- Chromatography, Liquid
- Glycation End Products, Advanced
- Humans
- Japan
- Reference Standards
- Serum Albumin
(analysis)
- Societies, Medical
- Tandem Mass Spectrometry
- Glycated Serum Albumin
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