<title>Blood aggregate size and velocity during blood sedimentation</title>

Abstract

The purpose of the study is to investigate the kinetics of red blood cell aggregates during sedimentation by means of an optical imaging. Sedimentation of normal red blood cells at 5% haematocrit in autologous plasma and the sedimentation of glutaraldehyde-hardened red blood cells was investigated. The sedimentation experiment lasted 30 minutes and changes of light intensity in the image plane of a 4f imaging system were recorded. The settling aggregate traces were extracted by a temporary analysis of those light intensity fluctuations and with the use of two-dimensional Fourier transform the velocity of the aggregates was obtained. From a spatial analysis of the light intensity fluctuations the correlation functions of the intensity were calculated and in this way the size of settling aggregates was achieved. We have shown that with the use of these methods we can find the velocity and size of aggregates formed during the sedimentation process. We have shown the influence of glutaraldehyde on the aggregate velocity and aggregate size.