Blood as an active colloidal system: The nonlinear nature of erythrocyte sedimentation in whole blood revealed by video recording with high spatial-temporal resolution

Abstract

An automatic device for the resolution of red-blood sedimentation at a high temporal level was designed. Using the principles of a technical vision system, a detailed analysis of red-blood sedimentation kinetics revealed the non-linear, macrokinetic behavior of whole-blood sedimentation, including several periods of the observed process. Dynamic changes in the density of the boundary between red blood and plasma, which were manifested in the oscillatory nature of process rate changes and the phenomenon of negative sedimentation, were revealed. Video recording of the process permitted the observation of nano- and microbubles of gas that were evacuating from blood during its settling. A hypothesis was suggested that represents blood as an active colloidal system that consists of at least three components, viz., plasma (liquid), cells (solid), and gas.