Glycosal: the first rapid, point-of-care test for the determination of hemoglobin A1c in patients with diabetes.
BACKGROUND
Glycosal is a rapid, point-of-care test using the established method of affinity chromatography for the quantitative determination of hemoglobin A1c (HbA1c). Glycosal enables the measurement of HbA1c to be performed in the diabetic clinic or doctor's office during a normal consultation, within minutes. The Glycosal test cartridge integrates with HaemaQuant, a compact spectrophotometric analyser equipped with a light emitting diode (LED) photo-optic detection system. An interactive liquid crystal display (LCD) provides the operator with an intuitive guide through the test procedure with the final result being expressed as HbA1c. Glycosal has a linear working range of at least 3%-18% HbA1c, requires approximately 10 microL of whole blood and generates a result in approximately 4 minutes. Glycosal has a mean coefficient of variation of less than 5% across its linear range.


METHODS
Glycosal was evaluated in the clinical environment by means of comparison to two routine HbA1c autoanalyser methods used in the Clinical Chemistry Department of the Malmo University Hospital, Sweden. The Variant (BioRad) and the Mono-S (Pharmacia) systems are both cation exchange high-performance liquid chromatography (HPLC) systems specifically measuring HbA1c. Fresh (< 2 days) EDTA anticoagulated blood samples were randomly selected from the routine diabetic clinic (n = 54) along with nondiabetic samples from consenting volunteers (n = 8).


RESULTS
The Variant and Mono-S HPLC methods showed excellent agreement compared to each other (correlation coefficient [r] > 0.99). The agreement between Glycosal and Variant (r = 0.98) and Glycosal and Mono-S (r > 0.98) HPLC methods were almost equally as significant. A further final evaluation of a 10 sample series (4%-10% HbA1c) of the hospital's HbA1c reference materials by Glycosal produced very strong agreement (r > 0.99) against the Mono-S HPLC.


CONCLUSIONS
The Glycosal rapid test is proven to be comparable to two high-precision cation exchange HPLC autoanalyzers and constitutes a low-cost, HbA1c measurement system for the management of individuals suffering from diabetes mellitus at the point-of-care.
Stevenson
T
T
Provalis Diagnostics Limited, United Kingdom. tonystevenson@Provalis.plc.uk
D002846:Chromatography, Affinity / Q000379:methods; D003920:Diabetes Mellitus / Q000097:blood*; D004867:Equipment Design; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D018670:Monitoring, Ambulatory / Q000295:instrumentation / Q000379:methods*; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods*; D019095:Point-of-Care Systems; D012016:Reference Values; D012044:Regression Analysis
D006442:Glycated Hemoglobin