Collection of blood on filter paper for measurement of glycated hemoglobin by affinity chromatography.

We present data on a filter-paper collection and assay method for measurement of glycated hemoglobin (gHb). Onto filter paper dipped into a solution of glucose oxidase (EC 1.1.3.4) and allowed to dry, approximately 20 microL of capillary blood was spotted. For analysis, we eluted the dried blood spot from the paper by soaking in water for 1 h, then measured the gHb in the eluate by affinity chromatography. Because the gHb significantly increased from day 1 to day 14 of storage, it was necessary to standardize the day of elution from the paper. We found a high correlation between gHb measured from samples stored for 14 days on treated paper and gHb measured by affinity chromatography from frozen whole blood or hemolysates (r = 0.96). This method is convenient, requiring small amounts of blood and little sample handling and assay time, and may be particularly useful in certain situations such as large-scale screening for diabetes.