Centre de Biochimie Structurale CBS, CNRS UMR 5048-INSERM UMR 1054, University of Montpellier, 34090, France.
Institut d'Electronique et des Systèmes IES, CNRS UMR 5214, University of Montpellier, Montpellier, 34000, France.
Phys Rev E. 2017 Nov;96(5-1):053114. doi: 10.1103/PhysRevE.96.053114. Epub 2017 Nov 27.
The morphology of dried blood droplets derives from the deposition of red cells, the main components of their solute phase. Up to now, evaporation-induced convective flows were supposed to be at the base of red cell distribution in blood samples. Here, we present a direct visualization by videomicroscopy of the internal dynamics in desiccating blood droplets, focusing on the role of cell concentration and plasma composition. We show that in diluted suspensions, the convection is promoted by the rich molecular composition of plasma, whereas it is replaced by an outward red blood cell displacement front at higher hematocrits. We also evaluate by ultrasounds the effect of red cell deposition on the temporal evolution of sample rigidity and adhesiveness.
干燥血滴的形态源于红细胞的沉积，红细胞是其溶质相的主要成分。到目前为止，蒸发诱导的对流流被认为是血液样本中红细胞分布的基础。在这里，我们通过视频显微镜直接观察干燥血滴的内部动力学，重点研究细胞浓度和血浆成分的作用。我们表明，在稀释悬浮液中，对流是由血浆丰富的分子组成所促进的，而在更高的血细胞比容时，对流则被向外的红细胞置换前沿所取代。我们还通过超声评估了红细胞沉积对样本刚性和粘性的时间演化的影响。
