A Comparison of Three Simple, Rapid Methods for Red Blood Cell Removal from Whole Blood, Which are Suitable for Measuring Biomarkers at the Point of Care

Abstract

Objective: Plasma is often used to assess the concentration of clinical markers, as the presence of red blood cells (RBCs) can interfere with the correct measurement of parameters. The objective was to select a simple, rapid and efficient method for RBCs removal from a small volume of whole blood usable at the point of care. Methods: Three alternative RBC removal methods were assessed from 50 µL of whole blood and compared with the centrifugation method. Two methods involved agglutination molecules, such as lectins or antibodies, whilst the third method used lateral filtration on a glass fiber paper strip. Results: In each case, the RBCs were efficiently separated from whole blood in less than five min at room temperature. In terms of marker recovery and residual hemoglobin concentration, the method that used antibodies performed the best and could be integrated into a process whereby plasma markers are measured from a small volume of whole blood at the point-of-care.