Microvolume blood-sampling device with low hemolysis and high consistent yield of serum components.

BACKGROUND Blood sampling by finger puncture is convenient, but the need for centrifugation and the problem of hemolysis remain, as does instability when samples must be shipped for analysis. We aimed to develop a blood-sampling device that provided high yields of serum with limited hemolysis and enabled preservation of serum components for at least 7 days at room temperature. METHODS For separation of blood cells, we devised a grooved, asymmetric, polysulfonate membrane impregnated with sucrose. We evaluated hemoglobin (Hb) concentrations in the serum, assay values for 15 frequently measured serum components (including glucose), and the stability of analytes in the device. RESULTS In sera from the new device, the Hb concentration was <or=0.43 mg/L. Recovered serum contained 65.0% +/- 4.2% (mean +/- SD; n = 41) of each of the serum components obtained by centrifugation. Serum components were stable in the device for 10 days at room temperature (25 degrees C). CONCLUSIONS The newly developed device allows recovery of 60% of serum components from microvolumes of blood by finger puncture with neither degradation of analytes at room temperature nor hemolysis.