Laboratory evaluation of a novel capillary blood sampling device for measuring eight clinical chemistry parameters and HbA1c.

BACKGROUND: The Demecal set enables medically unskilled persons to produce diluted plasma from a single drop of capillary blood at any time and place. The sample is mailed to a certified laboratory for analysis. A marker compound in the dilution buffer enables to correct for individual blood sampling variation. A test dependent factor corrects for recovery of analytes.
METHODS: Glucose, cholesterol, triglycerides, HDL and LDL cholesterol, creatinine, BUN, uric acid and HbA1c were evaluated. We studied the correction procedure for sampling variation by the marker compound, the precision of the analyzer in the low range, the influence of characteristics of the set on analyte recovery, and the stability of the samples at different temperatures.
RESULTS: Using the marker compound in the buffer, variation in sampling could be corrected accurately. For dilutions up to 15 times, the precision of the analyzer was sufficient. Application of test specific recovery factors gave a good correlation with results of venous blood samples. Samples were stable for 4 days at 4 degrees C, 2-3 days at room temperature and 1 day at 37 degrees C.
CONCLUSIONS: The Demecal set can be considered an alternative for venous blood sampling for the tested parameters, enabling patient friendly management of chronic disease.