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Yu Y, Zhang X, Lin K. Analytical performance evaluation of hemoglobin A1c on an ARKRAY HA-8160 analyzer with newly-developed mobile phase buffer. Pract Lab Med 2024; 40:e00414. [PMID: 38939102 PMCID: PMC11208942 DOI: 10.1016/j.plabm.2024.e00414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 05/21/2024] [Accepted: 05/29/2024] [Indexed: 06/29/2024] Open
Abstract
Background Most glycated hemoglobin A1c (HbA1c) analytical reagents used were obtained from the analyzer's manufacturer. However, clinical laboratories need more choices for HbA1c analytical reagents to overcome the limitations of dedicated reagents for special analyzers. We developed new mobile phase buffers as HbA1c diagnostic reagents and evaluated their analytical performance for the HbA1c assay. Methods Different mobile phase buffers used as HbA1c diagnostic reagents were prepared using different concentrations of sodium salts. According to the Clinical and Laboratory Standards Institute (CLSI) recommendation guidelines, the analytical performances of the newly developed mobile phase buffers were evaluated on an ARKRAY HA-8160 Analyzer. Both quality controls and clinical blood samples were used in these experiments. To assess the quality of the newly developed mobile phase buffers, precision, accuracy, linearity, carryover, interference, bias, correlation with commercial reagents, and stability were analyzed. Results The CVs of intra-assay precision and interassay precision of quality control and clinical.There were fewer than 1.00 % blood sample assays using the newly developed mobile phase buffer. The RDs of accuracy were less than 1.00 %. Linearity: R2 = 0.9998 in the concentration range of 4.40%-17.30 %. Carryover: 0.00 %. Reagent comparison revealed that the Pearson regression equation was Y = 0.9884x+0.05692 (R2 = 0.9977), and the Bland-Altman mean difference was -0.02650 % (CI: -0.2121 %-0.1591 %) between the two analytical reagents. Stability was also acceptable within 12 months. This mobile phase buffer showed good anti-interference ability. Conclusion The newly developed mobile phase buffers demonstrated good analytical performance and were suitable for clinical HbA1c assays on an ARKRAY HA-8160 Analyzer.
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Affiliation(s)
- Yuan Yu
- College of Laboratory Medicine, Hebei North University, No.11 Diamond South Road, High-tech Development Area, Zhangjiakou City, Hebei Province, 075000, China
- Department of Clinical Laboratory, Air Force Medical Center, Air Force Medical University, No.30 Fucheng Road, Haidian District, Beijing, 100142, China
| | - Xiaoyun Zhang
- College of Laboratory Medicine, Hebei North University, No.11 Diamond South Road, High-tech Development Area, Zhangjiakou City, Hebei Province, 075000, China
| | - Kai Lin
- Department of Clinical Laboratory, Air Force Medical Center, Air Force Medical University, No.30 Fucheng Road, Haidian District, Beijing, 100142, China
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2
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Zhou X, Lai W, Zhong J, Yang Y, Chen Z, Zhang C. Point-of-care detection of glycated hemoglobin using a novel dry chemistry-based electrochemiluminescence device. Anal Chim Acta 2023; 1279:341829. [PMID: 37827624 DOI: 10.1016/j.aca.2023.341829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 08/30/2023] [Accepted: 09/15/2023] [Indexed: 10/14/2023]
Abstract
As a good biomarker to reflect the average level of blood glucose, glycated hemoglobin (HbA1c) is mainly used for long-term glycemic monitoring and risk assessment of complications in diabetic patients. Previous analysis methods for HbA1c usually require complex pretreatment processes and large-scale biochemical analyzers, which makes it difficult to realize the point-of-care testing (POCT) of HbA1c. In this work, we have proposed a three-electrode dry chemistry-based electrochemiluminescence (ECL) biosensor and its self-contained automatic ECL analyzer. In this enzymatic biosensor, fructosyl amino-caid oxidase (FAOD) reacts with the hydrolysis product of HbA1c, and the produced hydrogen peroxide further reacts with luminol under the appropriate driving voltage, generating photons to realize the quantitative detection of HbA1c. Under optimized conditions, the biosensors have a good linear response to different concentrations of fructosyl valine (FV) ranging from 0.05 to 2 mM, with a limit of detection of 2 μM. The within-batch variation is less than 15%, and the biosensors still have 78% of the initial response after the accelerated aging test of 36 h at 37 °C. Furthermore, the recoveries for different concentrations of samples in whole blood were within 92.3-99.7%. These results illustrate that the proposed method has the potential for use in POCT of HbA1c.
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Affiliation(s)
- Xinya Zhou
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, 510631, China; Guangdong Provincial Key Laboratory of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, 510631, China
| | - Wei Lai
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, 510631, China; Guangdong Provincial Key Laboratory of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, 510631, China
| | - Jinbiao Zhong
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, 510631, China; Guangdong Provincial Key Laboratory of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, 510631, China
| | - Yang Yang
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, 510631, China; Guangdong Provincial Key Laboratory of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, 510631, China
| | - Zhenyu Chen
- Guangzhou First People's Hospital Nansha Hospital, Guangzhou, 511457, China.
| | - Chunsun Zhang
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, 510631, China; Guangdong Provincial Key Laboratory of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou, 510631, China.
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Current Status of HbA1c Biosensors. SENSORS 2017; 17:s17081798. [PMID: 28777351 PMCID: PMC5579747 DOI: 10.3390/s17081798] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Revised: 07/24/2017] [Accepted: 08/01/2017] [Indexed: 01/08/2023]
Abstract
Glycated hemoglobin (HbA1c) is formed via non-enzymatic glycosylation reactions at the α–amino group of βVal1 residues in the tetrameric Hb, and it can reflect the ambient glycemic level over the past two to three months. A variety of HbA1c detection methods, including chromatography, immunoassay, enzymatic measurement, electrochemical sensor and capillary electrophoresis have been developed and used in research laboratories and in clinics as well. In this review, we summarize the current status of HbA1c biosensors based on the recognition of the sugar moiety on the protein and also their applications in the whole blood sample measurements.
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Hattan SJ, Parker KC, Vestal ML, Yang JY, Herold DA, Duncan MW. Analysis and Quantitation of Glycated Hemoglobin by Matrix Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2016; 27:532-541. [PMID: 26733405 DOI: 10.1007/s13361-015-1316-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 11/24/2015] [Accepted: 11/25/2015] [Indexed: 06/05/2023]
Abstract
Measurement of glycated hemoglobin is widely used for the diagnosis and monitoring of diabetes mellitus. Matrix assisted laser desorption/ionization (MALDI) time of flight (TOF) mass spectrometry (MS) analysis of patient samples is used to demonstrate a method for quantitation of total glycation on the β-subunit of hemoglobin. The approach is accurate and calibrated with commercially available reference materials. Measurements were linear (R(2) > 0.99) across the clinically relevant range of 4% to 20% glycation with coefficients of variation of ≤ 2.5%. Additional and independent measurements of glycation of the α-subunit of hemoglobin are used to validate β-subunit glycation measurements and distinguish hemoglobin variants. Results obtained by MALDI-TOF MS were compared with those obtained in a clinical laboratory using validated HPLC methodology. MALDI-TOF MS sample preparation was minimal and analysis times were rapid making the method an attractive alternative to methodologies currently in practice.
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Affiliation(s)
| | | | | | - Jane Y Yang
- Department of Pathology, University of California San Diego, La Jolla, CA, 92093-0612, USA
| | - David A Herold
- Department of Pathology, University of California San Diego, La Jolla, CA, 92093-0612, USA
- VA San Diego Healthcare System, PALMS, MS 113, San Diego, CA, 92161, USA
| | - Mark W Duncan
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado School of Medicine, MS 8106, Aurora, CO, 80045, USA
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5
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Jo EJ, Mun H, Kim MG. Homogeneous Immunosensor Based on Luminescence Resonance Energy Transfer for Glycated Hemoglobin Detection Using Upconversion Nanoparticles. Anal Chem 2016; 88:2742-6. [DOI: 10.1021/acs.analchem.5b04255] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Eun-Jung Jo
- Department of Chemistry,
School of Physics and Chemistry, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712, Republic of Korea
| | - Hyoyoung Mun
- Department of Chemistry,
School of Physics and Chemistry, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712, Republic of Korea
| | - Min-Gon Kim
- Department of Chemistry,
School of Physics and Chemistry, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712, Republic of Korea
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Bexelius C, Lundberg J, Wang X, Berg J, Hjelm H. Annual Medical Costs of Swedish Patients with Type 2 Diabetes Before and After Insulin Initiation. Diabetes Ther 2013; 4:363-374. [PMID: 23959539 PMCID: PMC3889328 DOI: 10.1007/s13300-013-0035-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Indexed: 11/09/2022] Open
Abstract
INTRODUCTION Although insulin is one of the most effective interventions for the treatment of type 2 diabetes, its disadvantages incur substantial medical cost. This study was designed to evaluate the medical costs of Swedish type 2 diabetic patients initiating insulin on top of metformin and/or sulfonylurea (SU), and to evaluate if costs before and after insulin initiation differ for patients where insulin is initiated above or below the recommended glycosylated hemoglobin (HbA1c) level (7.5%). METHODS This was a register-based retrospective cohort study in which patients were identified from the Sörmland county council diabetes register. Patients being prescribed at least one prescription of metformin and/or SU from 2003 to 2010, and later prescribed insulin, were included. RESULTS One hundred patients fulfilled the inclusion criteria and had at least 1 year of follow-up. The mean age was 61 years and 59% of patients were male. Mean time since diagnosis was 4.1 years, and since initiation of insulin was 2.2 years. The mean HbA1c level at index date was 8.0%. Total mean costs for the whole cohort were SEK 17,230 [standard deviation (SD) 17,228] the year before insulin initiation, and SEK 31,656 (SD 24,331) the year after insulin initiation (p < 0.0001). When stratifying by HbA1c level, patients with HbA1c <7.5% had total healthcare costs of SEK 17,678 (SD 12,946) the year before the index date and SEK 35,747 (SD 30,411) the year after (p < 0.0001). Patients with HbA1c levels ≥7.5% had total healthcare costs of SEK 16,918 (SD 19,769) the year before the index date and SEK 28,813 (SD 18,779) the year after (p < 0.0001). CONCLUSION Despite the small sample size, this study demonstrates that mean annual medical costs almost double the year after patients are initiated on insulin. The costs increased the year after insulin initiation, regardless of the HbA1c level at initiation of insulin, and the largest increase in costs were due to increased filled prescriptions.
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Affiliation(s)
- Christin Bexelius
- OptumInsight, Klarabergsviadukten 90, House D, 111 64 Stockholm, Sweden
| | | | - Xuan Wang
- OptumInsight, Klarabergsviadukten 90, House D, 111 64 Stockholm, Sweden
| | - Jenny Berg
- OptumInsight, Klarabergsviadukten 90, House D, 111 64 Stockholm, Sweden
- Division of Cardiovascular Epidemiology, Institute of Environmental Medicine, Karolinska Institute, Solna, Sweden
| | - Hans Hjelm
- Medicine Clinic, Nyköping Hospital, Nyköping, Sweden
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7
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Liu G, Iyengar SG, Gooding JJ. An Electrochemical Impedance Immunosensor Based on Gold Nanoparticle-Modified Electrodes for the Detection of HbA1c in Human Blood. ELECTROANAL 2012. [DOI: 10.1002/elan.201200233] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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8
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Liu G, Khor SM, Iyengar SG, Gooding JJ. Development of an electrochemical immunosensor for the detection of HbA1c in serum. Analyst 2012; 137:829-32. [DOI: 10.1039/c2an16034j] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Sánchez-Mora C, Rodríguez-Oliva MS, Fernández-Riejos P, Mateo J, Polo-Padillo J, Goberna R, Sánchez-Margalet V. Evaluation of two HbA1c point-of-care analyzers. Clin Chem Lab Med 2011; 49:653-7. [DOI: 10.1515/cclm.2011.101] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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10
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Antunes MV, Wagner SC, Camargo JL, Linden R. Standardization of method for determining glycosylated hemoglobin (Hb A1c) by cation exchange high performance liquid chromatography. BRAZ J PHARM SCI 2009. [DOI: 10.1590/s1984-82502009000400007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Hemoblobin A1c is the most important parameter for the monitoring of metabolic control of patients with diabetes mellitus. The purpose of this study was to adapt the Mono S method to a conventional HPLC system, allowing highly selective HbA1c determination without the acquisition of kits or the use of dedicated systems The results obtained were compared to the Tinaquant® immune turbidimetric method and the Bio-Rad Variant® chromatographic method. The developed method presented intra-study precision (C.V. %) of 1.39-3.65 and inter-study precision (C.V. %) of 2.80-3.02%. The determination coefficients among methods were: HPLC Mono S x Tinaquant®: r²: 0.9856 (n=60) and HPLC Mono S x HPLC Bio-Rad Variant®: r²: 0.9806 (n=16). A conversion equation between HPLC Mono S and Bio-Rad Variant® was calculated allowing yielding comparable and interchangeable values. The HPLC Mono-S is a precise, low-cost method which yields similar values to the Bio-Rad Variant® method on conventional HPLC equipment.
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11
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Penttilä IM, Halonen T, Punnonen K, Tiikkainen U. Best use of the recommended IFCC reference method, material and values in HbA1Canalyses. Scandinavian Journal of Clinical and Laboratory Investigation 2009; 65:453-62. [PMID: 16179278 DOI: 10.1080/00365510510025809] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The results of Finnish HbA(1C) surveys (Labquality Ltd.) during the past 10 years have undergone continuous improvement with smaller overall coefficients of variation for the HbA(1C) mean values of all methods (from 7.5 to 5.4% for normal and from 8.9 to 4.7% for diabetic samples). Most of the HbA(1C) methods are certified for traceability to the Diabetes Control and Complication Trial (DCCT) designated comparison method, which originally was a high-performance liquid chromatography (HPLC) method (Bio-Rex 70, Bio-Rad) but is no longer in routine use. It was therefore important that the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) had prepared both reference preparations and method for the determination of HbA(1C). However, the very demanding reference method is not realistic for use in clinical laboratories. According to the present study, the mean HbA(1C) values of the Labquality Ltd. showed significant correlations to the HbA(1C) values of The European Reference Laboratory for Glycohemoglobin (r = 0.999) and to the values using the IFCC method (r = 0.999). The reference values of the IFCC method (mainly those of the manufacturer) range from 2.85 to 3.81%, being significantly lower than the present DCCT values (4.0-6.1%). Since it may take some time before consumers are ready to accept the new IFCC reference values for general use, we propose that the IFCC reference materials and method should be used for calibration of the present methods to the well-known DCCT levels.
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Affiliation(s)
- I M Penttilä
- Department of Clinical Chemistry, University Hospital, Kuopio, Finland
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12
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The investigation of recognition interaction between phenylboronate monolayer and glycated hemoglobin using surface plasmon resonance. Anal Biochem 2008; 375:90-6. [DOI: 10.1016/j.ab.2008.01.004] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2007] [Revised: 01/02/2008] [Accepted: 01/03/2008] [Indexed: 11/21/2022]
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13
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Syakhovich VE, Parul DA, Ruta EY, Bushuk BA, Bokut SB. 1,8-Anilinonaphthalene sulfonate binds to central cavity of human hemoglobin. Biochem Biophys Res Commun 2004; 317:761-7. [PMID: 15081405 DOI: 10.1016/j.bbrc.2004.03.111] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2004] [Indexed: 11/29/2022]
Abstract
Binding of 1,8-anilinonaphthalene sulfonate (1,8-ANS) to main (HbA(1)) and glycosylated (HbA(1C)) forms of human oxyhemoglobin in the presence/absence of inositolhexaphosphate (IHP) in 50 mM potassium phosphate buffer, pH 7.4, was studied by time-correlated single photon counter with subnanosecond time resolution. The redistribution of contributions of the most long-lived and the most short-lived fluorescent decay components in the presence of IHP provides an evidence of the probe binding within oxyhemoglobin central cavity, namely DPG-binding site. Finally, it was shown that the fluorescent probe is extremely sensitive for hemoglobin central cavity modification, provided by the carbohydrate moiety in case of 1,8-ANS interactions with HbA(1C).
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Affiliation(s)
- Vitaly E Syakhovich
- International Sakharov Environmental University, Dolgobrodskaya St. 23, Minsk 220009, Belarus
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14
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Sreenivasan K. Imparting affinity sites for adenosine triphosphate on the surface of polyurethane through molecular imprinting. J Appl Polym Sci 2004. [DOI: 10.1002/app.21142] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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15
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Hoelzel W, Weykamp C, Jeppsson JO, Miedema K, Barr JR, Goodall I, Hoshino T, John WG, Kobold U, Little R, Mosca A, Mauri P, Paroni R, Susanto F, Takei I, Thienpont L, Umemoto M, Wiedmeyer HM. IFCC Reference System for Measurement of Hemoglobin A1c in Human Blood and the National Standardization Schemes in the United States, Japan, and Sweden: A Method-Comparison Study. Clin Chem 2004; 50:166-74. [PMID: 14709644 DOI: 10.1373/clinchem.2003.024802] [Citation(s) in RCA: 500] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Abstract
Background: The national programs for the harmonization of hemoglobin (Hb)A1c measurements in the US [National Glycohemoglobin Standardization Program (NGSP)], Japan [Japanese Diabetes Society (JDS)/Japanese Society of Clinical Chemistry (JSCC)], and Sweden are based on different designated comparison methods (DCMs). The future basis for international standardization will be the reference system developed by the IFCC Working Group on HbA1c Standardization. The aim of the present study was to determine the relationships between the IFCC Reference Method (RM) and the DCMs.
Methods: Four method-comparison studies were performed in 2001–2003. In each study five to eight pooled blood samples were measured by 11 reference laboratories of the IFCC Network of Reference Laboratories, 9 Secondary Reference Laboratories of the NGSP, 3 reference laboratories of the JDS/JSCC program, and a Swedish reference laboratory. Regression equations were determined for the relationship between the IFCC RM and each of the DCMs.
Results: Significant differences were observed between the HbA1c results of the IFCC RM and those of the DCMs. Significant differences were also demonstrated between the three DCMs. However, in all cases the relationship of the DCMs with the RM were linear. There were no statistically significant differences between the regression equations calculated for each of the four studies; therefore, the results could be combined. The relationship is described by the following regression equations: NGSP-HbA1c = 0.915(IFCC-HbA1c) + 2.15% (r2 = 0.998); JDS/JSCC-HbA1c = 0.927(IFCC-HbA1c) + 1.73% (r2 = 0.997); Swedish-HbA1c = 0.989(IFCC-HbA1c) + 0.88% (r2 = 0.996).
Conclusion: There is a firm and reproducible link between the IFCC RM and DCM HbA1c values.
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Bossi A, Piletsky SA, Piletska EV, Righetti PG, Turner AP. Surface-grafted molecularly imprinted polymers for protein recognition. Anal Chem 2001; 73:5281-6. [PMID: 11721930 DOI: 10.1021/ac0006526] [Citation(s) in RCA: 255] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A technique for coating microplate wells with molecularly imprinted polymers (MIPs) specific for proteins is presented. 3-Aminophenylboronic acid was polymerized in the presence of the following templates: microperoxidase, horseradish peroxidase, lactoperoxidase, and hemoglobin, via oxidation of the monomer by ammonium persulfate. This process resulted in the grafting of a thin polymer layer to the polystyrene surface of the microplates. Imprinting resulted in an increased affinity of the polymer toward the corresponding templates. The influence of the washing procedure, template concentration, and buffer pH on the polymer affinity was analyzed. It was shown that the stabilizing function of the support and spatial orientation of the polymer chains and template functional groups are the major factors affecting the imprint formation and template recognition. Easy preparation of the MIPs, their high stability, and their ability to recognize small and large proteins, as well as to discriminate molecules with small variations in charge, make this approach attractive and broadly applicable in biotechnology, assays and sensors.
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Affiliation(s)
- A Bossi
- Institute of BioScience and Technology, Cranfield University, Bedfordshire, UK.
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17
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Chachou A, Randoux C, Millart H, Chanard J, Gillery P. Influence of in vivo hemoglobin carbamylation on HbA1c measurements by various methods. Clin Chem Lab Med 2000; 38:321-6. [PMID: 10928652 DOI: 10.1515/cclm.2000.046] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Increased carbamylated hemoglobin formed in erythrocytes during uremia may interfere with HbA1c assays, but few studies compared directly both parameters. We measured carbamylated hemoglobin by HPLC in 45 non-diabetic uremic patients (16 with acute and two with chronic renal failure, 27 with transplant recipients) as 57.8 +/- 22.3 microg carbamylvaline/g Hb (mean +/- standard deviation) vs. 31.6 +/- 5.1 in 15 controls (+83%, p < 0.001). In these samples, HbA1c was evaluated by three ion-exchange HPLC methods, 1: Diamat (BioRad), 2: A1c2.2 (Tosoh) and 3: HA8140 (Menarini), and one immunoassay method (Tinaquant II Roche). Whichever the method, mean HbA1c values obtained increased in patients with high (> 60 microg carbamylvaline/g Hb) vs. low (< 45) carbamylated hemoglobin values (+0.08 to 0.25% of total Hb), but differences were not significant. Minor peaks on the chromatograms were however increased in parallel to carbamylated hemoglobin. HbA1c values over 6% were found in 4, 1, 2 and 0 samples, with HPLC 1, 2, 3 and immunoassay, respectively. Fructosamine values were not significantly altered. Our results show that Hb adducts, whether due to carbamylation or to other chemical reactions, interfere to a variable extent with different HbA1c assay methods, and confirm that HbA1c values should be interpreted with caution in uremic patients.
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Affiliation(s)
- A Chachou
- Central Laboratory of Biochemistry, Robert Debré Hospital, CHU of Reims, France
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Affiliation(s)
- D J Anderson
- Department of Chemistry, Cleveland State University, Ohio 44115, USA
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Koskinen LK, Korpela MM, Lahtela JT, Laippala PJ, Pikkarainen PH, Koivula TA. Effect of acetaldehyde and acetylsalicylic acid on HbA1c chromatography in the FPLC method with Mono S cation exchanger. Clin Chim Acta 1998; 275:53-61. [PMID: 9706843 DOI: 10.1016/s0009-8981(98)00076-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The effects of alcohol and aspirin on HbA1c chromatography in the Mono S method were studied in vitro and in vivo. A modified chromatography with enhanced resolution was used, making possible detailed examination of minor interfering peaks included in the routine HbA1c value. Incubation with acetylsalicylic acid increased a hemoglobin fraction separate from HbA1c. In vivo this fraction was elevated by 0.1% of the total hemoglobin during therapeutic aspirin ingestion for one month. In vitro acetaldehyde generated two labile hemoglobin fractions and slightly increased a minor stable fraction which was also elevated in vivo in both alcoholics and heavy drinkers. In relation to the HbA1c concentration, this stable fraction was equal in both alcoholic groups. We conclude that the in vivo effects of both aspirin and alcohol are negligible in routine HbA1c determination. Factors other than acetaldehyde might account for the unexpected HbA1c values in alcoholics.
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Affiliation(s)
- L K Koskinen
- Department of Clinical Chemistry, Tampere University Hospital, Finland
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20
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Koskinen LK, Ala-Houhala IO, Lahtela JT, Laippala PJ, Koivula TA. Does uremia interfere with HbA1c results in the FPLC method with Mono S cation exchanger? Clin Chim Acta 1998; 273:69-79. [PMID: 9620471 DOI: 10.1016/s0009-8981(98)00030-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
To study the effect of uremia on hemoglobin A1c determination by the Mono S FPLC method, samples from uremic patients, with and without diabetes, and controls, were analysed with a modified chromatography with enhanced resolution. Besides specific HbA1c, four minor peaks could be seen, included in routine HbA1c values. Two of these differed in concentration in the patient groups studied: a shoulder-like peak close to the specific HbA1c (S fraction) and a slightly less cationic minor peak (M fraction). Both S and M peaks were higher in uremic than in nonuremic subjects, but the M peak was associated more with diabetes. In the nondiabetic group, the mean routine HbA1c value was 0.8% units higher in uremic than nonuremic individuals. The specific HbA1c was nondependent on uremia. Thus, in uremic patients, there seems to be falsely elevated HbA1c values, mainly because of small interfering hemoglobin fractions, not specific HbA1c.
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Affiliation(s)
- L K Koskinen
- Department of Clinical Chemistry, Tampere University Hospital, Finland
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Finke A, Kobold U, Hoelzel W, Weykamp C, Miedema K, Jeppsson JO. Preparation of a candidate primary reference material for the international standardisation of HbA1c determinations. Clin Chem Lab Med 1998; 36:299-308. [PMID: 9676387 DOI: 10.1515/cclm.1998.051] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
We prepared a candidate primary reference material for the forthcoming international standardisation of beta-N-terminal glycated hemoglobin A measurements. It consists of well-defined mixtures of purified beta-N-terminal glycated hemoglobin A and non-glycated hemoglobin A. First, beta-N-terminal glycated hemoglobin A and non-glycated hemoglobin A were isolated, purified to homogeneity, and characterised. The techniques used were cation exchange and affinity chromatography for the purification, and high performance liquid chromatography, capillary isoelectric focusing, electrospray ionisation mass spectrometry, and peptide mapping for the characterisation. Hemoglobins from blood of healthy, non-diabetic volunteers were obtained with a purity of > 99.5% for non-glycated hemoglobin A and of > 98.5% for beta-N-terminal glycated hemoglobin A. However, results from peptide mapping indicate that the beta-N-terminal glycated hemoglobin A preparations still contain some non-beta-N-terminal glycated hemoglobins, co-eluting with beta-N-terminal glycated hemoglobin A. The exact content of beta-N-terminal glycated hemoglobin A in these preparations could be determined by a procedure consisting of standard addition, enzymatic cleavage and quantification of the resulting beta-N-terminal peptides to be in the range from 95-97.5%. Since the beta-N-terminal glycated hemoglobin A and non-glycated hemoglobin A content could be exactly determined in the materials prepared, mixtures of both components could be successfully used to calibrate the candidate reference methods.
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Affiliation(s)
- A Finke
- Boehringer Mannheim GmbH, Penzberg, Germany.
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Kobold U, Jeppsson JO, Dülffer T, Finke A, Hoelzel W, Miedema K. Candidate reference methods for hemoglobin A1c based on peptide mapping. Clin Chem 1997. [DOI: 10.1093/clinchem/43.10.1944] [Citation(s) in RCA: 132] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
AbstractA reference method that specifically measures hemoglobin (Hb) A1c is an essential part of the reference system for the international standardization of Hb A1c/glycohemoglobin. We have developed a new method for quantification, based on the specific N-terminal residue of the hemoglobin β-chains. Enzymatic cleavage of the intact hemoglobin molecule with endoproteinase Glu-C has been optimized to obtain the β-N-terminal hexapeptides of Hb A1c and Hb A0. These peptides have been separated by reversed-phase HPLC and quantitated by electrospray ionization-mass spectrometry (method A) or by capillary electrophoresis (method B). With these peptides and hyphenated separation techniques, it has been possible to overcome the insufficient resolution of currently used protein separation systems for Hb A1c.
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Affiliation(s)
- Uwe Kobold
- Boehringer Mannheim GmbH Lab Diagnostics, Research Center Tutzing, Bahnhofstr. 9-15, D-82327 Tutzing, Germany
| | - Jan-Olof Jeppsson
- Department of Clinical Chemistry, University of Lund, Malmö University Hospital, S-20502 Malmö, Sweden
| | - Thomas Dülffer
- Boehringer Mannheim GmbH Lab Diagnostics, Research Center Tutzing, Bahnhofstr. 9-15, D-82327 Tutzing, Germany
| | - Andreas Finke
- Boehringer Mannheim GmbH Lab Diagnostics, Research Center Tutzing, Bahnhofstr. 9-15, D-82327 Tutzing, Germany
| | - Wieland Hoelzel
- Boehringer Mannheim GmbH Lab Diagnostics, Research Center Tutzing, Bahnhofstr. 9-15, D-82327 Tutzing, Germany
| | - Kor Miedema
- De Weezenlanden Ziekenhuis, Groot Wezenland 20, NL-8000 GM Zwolle, The Netherlands
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