The Reflotron Total Cholesterol assay in heparinized venous and capillary blood.

We recently evaluated the Reflotron Total Cholesterol dry chemistry assay by examining the calibration and the accuracy of the assay in serum, whole venous EDTA-blood and capillary EDTA blood. We now describe a study on the analysis in heparinized venous and heparinized finger stick blood. Cholesterol assays in venous serum and plasma, and in finger capillary blood and plasma (all with heparin) were compared. Finger capillary blood was obtained in two ways: 1. in heparinized capillaries; 2. in a Becton Dickinson microtainer that could be centrifuged for separation of the plasma. Venous blood was obtained in plain tubes (for serum) and heparinized tubes to obtain venous whole blood and also venous plasma. We did not, on average, find large differences between the concentrations of cholesterol in the various materials. The regression equations for finger capillary whole blood and venous whole blood however show higher slopes than the others. Inaccuracy due to the sampling technique appears to be no greater for finger capillary samples than for venous samples.