GLYCOHEMOGLOBIN FILTER ASSAY FOR DOCTORS OFFICES BASED ON BORONIC ACID AFFINITY PRINCIPLE

We present a new filter assay for the determination of glycohemoglobin as a unique application of the boronic acid affinity principle. With the use of a water-soluble blue-colored boronic acid derivative and a specific precipitation method for hemoglobin, total hemoglobin includi ng bound boronic acid is precipitated and collected on a filter strip before quantification. Hemoglobin and boronic acid are quantified by a dual-wavelength reflectometric measurement, and the result is reporte d directly as percent glycohemoglobin. The test is simple, quick, and designed as a doctors' office test for the monitoring and management o f diabetes. The imprecision of the assay is <4% over the range 3-18% H b A(1c), and the method is linear up to at least 20% Hb A(1c). Compari sons with four well-established glycohemoglobin methods yielded correl ation coefficients ranging from 0.94 to 0.99, with slopes from 0.94 to 1.01.