Abstract
Surface tension is a physical phenomenon that occurs as a result of the presence of a cohesive force between molecules of the liquid. Many biological processes depend on wetting and interfacial tension. The physical properties of the blood are of great importance according to their effect on the circulatory system. One of these physical properties is surface tension. As the blood could be treated as suspension, this study aims to study the effect of physical properties of erythrocytes on the surface tension of the blood. Blood surface tension was measured by maximum bubble pressure. This method offers the most accurate method to evaluate the surface tension of biofluid. Strong correlations between blood surface tension and mean erythrocytes volume, and the aggregation index of erythrocytes were found. No correlations between blood surface tension and erythrocytes Zeta potential and erythrocytes deformability were found. It can be concluded that not only the biochemical factors influence blood surface tension but also the physical properties of erythrocytes.