Abstract
A new attempt to use Polyvinylpyrrolidone (PVP) as a bio-drag reducing polymer agent for human blood flow has been studied. PVP was added at 0, 500, 750 and 1000 part per million (ppm) and mixed with human blood at room temperature for 2 minutes. Then, a cone on plate rheometer was used to investigate the effectiveness of PVP agent on blood rheological properties. The results showed significant effecting of PVP on blood fluidity characteristics, where the viscosity decreased as the PVP content increased or as a shear rate increased. For a certain shear rate, the shear stress decreased as PVP content increased. These changes will lead to increased mixing efficiency within the capillaries, increased oxygen transportation, increased tissue perfusion, modified red blood cells (RBCs) distribution, reduced pressure drop gradients, enhanced turbulent flow tendency, enhanced viscoelasticity nature of the blood and its strengthened non-Newtonian pattern. Also, the results showed that the viscosity-shear stress relationships become more linear at higher PVP concentrations. PVP addition caused no shifting in UV-absorbing positions and only moderate intensity changing. Atomic force microscopy (AFM) parameters provide other indicators about the role of PVP as a drag reduction agent for blood flow, where all of the amplitude, hybrid and special parameters decreased significantly.