	overview
	product listing A - Z
	applications listing A - Z
	catalog - biomedical research
	general research
	clinical laboratory
	genetic analysis
	drug discovery research
	immunology
	lab automation
	disease management and primary care

SYNCHRON® Hemoglobin A1c (HbA1c)

Printer Friendly

Related Product Information

Measurement of hemoglobin A1c (HbA1c) is accepted as a method for long-term glucose control in patients with diabetes mellitus (a chronic disorder associated with disturbances in carbohydrate, fat, and protein metabolism and characterized by hyperglycemia).¹

Determination of HbA1c is an important diagnostic tool for monitoring the efficiency of dietary control and therapy during treatment of diabetes mellitus. Long-term treatment of the disease emphasizes control of blood glucose levels to prevent acute complications of ketosis and hyperglycemia. In addition, long-term complications such as retinopathy, neuropathy, and cardiovascular disease can be minimized if blood glucose levels are efficiently controlled.1, 2, 3

The process of conversion from hemoglobin A to hemoglobin A1c depends on the blood glucose concentration. Since the average half-life of a red blood cell is 60 days, measurement of hemoglobin HbA1c reflects the mean daily blood glucose concentration over the preceding two months. It provides a much better indication of glycemic control than blood or urinary glucose determinations.1, 4, 5, 6

Methodology

SYNCHRON® systems utilize two unique cartridges, Hb and A1c, to determine HbA1c concentration as a percentage of total hemoglobin.

Hemoglobin Reagent is used to measure total hemoglobin concentration by a colorimetric method. The systems automatically proportion the appropriate sample and reagent volumes into the cuvette and monitor the change in absorbance at 560 nanometers. This change in absorbance is directly proportional to the concentration of total hemoglobin in the sample and is used by the systems to calculate and express total hemoglobin concentration.

A1c Reagent is used to measure the hemoglobin A1c concentration by a turbidimetric immunoinhibition method. In the reaction, hemoglobin A1c antibodies combine with hemoglobin A1c from the sample to form soluble antigen-antibody complexes. Polyhaptens from the reagent then bind with the excess antibodies and the resulting agglutinated complex is measured turbidimetrically. The systems automatically proportion the appropriate sample and reagent volumes into the cuvette and monitor the change in absorbance at 340 nanometers. This change in absorbance is inversely proportional to the percent concentration of hemoglobin A1c in the sample and is used by the systems to calculate and express hemoglobin A1c concentration as a percentage of total hemoglobin.

SYNCHRON® systems utilize two unique cartridges, Hb and A1c, to determine HbA1c concentration as a percentage of total hemoglobin.

Chemical Reaction Scheme

Performance Characteristics

CX Correlation*

Recoveries for 112 specimens were compared between the SYNCHRON system and an HPLC mehtod.

SLOPE = 1.02 INTERCEPT = 0.24 N = 96

MEAN X = 7.17 R = 0.97 MEAN Y = 7.08

CX Correlation*

Recoveries for 112 specimens were compared between the SYNCHRON system and an HPLC mehtod.

SLOPE = 1.02 INTERCEPT = 0.24 N = 96

MEAN X = 7.17 R = 0.97 MEAN Y = 7.08

Linearity*

Linerarity was evaluated by preparing dilutions of an elevated specimen.

Linearity*

Linerarity was evaluated by preparing dilutions of an elevated specimen.

Precision

A properly operating SYNCHRON System should exhibit precision values values less than or equal to the following:

Within-Run

Sample Type - Whole Blood Hemolysate

1 SD %HbA1c - 0.04

Changeover Value** %HbA1c - 8.0

%CV - 5.0

Total

Sample Type - Whole Blood Hemolysate

1 SD %HbA1c - 0.60

Changeover Value** %HbA1c - 8.0

%CV - 7.5

A properly operating SYNCHRON System should exhibit precision values values less than or equal to the following:

Within-Run

Sample Type - Whole Blood Hemolysate

1 SD %HbA1c - 0.04

Changeover Value** %HbA1c - 8.0

%CV - 5.0

Total

Sample Type - Whole Blood Hemolysate

1 SD %HbA1c - 0.60

Changeover Value** %HbA1c - 8.0

%CV - 7.5

Characteristics

Analyte	Units
Hemoglobin, Sample Type - whole blood hemolysate	6 to 24 g/dl
A1c, Sample Type - whole blood hemolysate	0.3 to Cal 5
%HbA1C, Sample Type - whole blood hemolysate	2 to 20%

References

1. Sperling, M.A., ed., Physician’s Guide to Insulin-Dependent (Type 1) Diabetes: Diagnosis and Treatment, American Diabetes Association, Inc., Alexandria, VA (1988).

2. Rochman, H., “Hemoglobin A1c and Diabetes Mellitus,” Ann Clin Lab Sci., Vol. 10, No. 2, pp. 111-115 (1980).

3. Nathan, et al., “The Effects of Intensive Treatment of Diabetes on the Development and Progression of Long-Term Complications in Insulin-dependent Diabetes Mellitus,” New England Journal of Medicine, No. 329, pp. 977-986 (1993).

4. Heinze, E., Kohne, E., Meissner, C., et al., “Hemoglobin A1c (HbA1c) in Children with Long Standing and Newly Diagnosed Diabetes Mellitus,” Acta Paediatr Scand., No. 68, pp. 609-612 (1979).

5. Mortensen, H.B., “Glycated Hemoglobin,” Dan Med Bull., Vol. 32, No. 6, pp. 309-328 (1985).

6. Lehmann, P., “Homogenous Immunoturbimetric Assay for Hemoglobin A1c Adaptable for Most Clinical Chemistry Analyzers:

A New Concept in the Care of Diabetic Patients,” AACC 45th National Meeting (1993).

*These precision, linearity and correlation studies were obtained in limited

evaluations and are not intended to represent performance specifications for this reagent.

**When the mean of the test precision data is less than or equal to the changeover value, compare the test SD to the SD guideline given above to determine the acceptability of the precision testing. When the mean of the test precision data is greater than the changeover value, compare the test %CV to the %CV guideline given above to determine acceptability. Changeover value = (SD guideline/CV guideline) x 100.

***Diamat is a registered trademark of Bio-Rad Laboratories, Inc.

Note: Not all products are available in all countries.