Centro de Estudos de Fenómenos de Transporte, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom.
Biomicrofluidics. 2013 May 17;7(3):34102. doi: 10.1063/1.4804649. eCollection 2013.
The non-Newtonian properties of blood are of great importance since they are closely related with incident cardiovascular diseases. A good understanding of the hemodynamics through the main vessels of the human circulatory system is thus fundamental in the detection and especially in the treatment of these diseases. Very often such studies take place in vitro for convenience and better flow control and these generally require blood analogue solutions that not only adequately mimic the viscoelastic properties of blood but also minimize undesirable optical distortions arising from vessel curvature that could interfere in flow visualizations or particle image velocimetry measurements. In this work, we present the viscoelastic moduli of whole human blood obtained by means of passive microrheology experiments. These results and existing shear and extensional rheological data for whole human blood in the literature enabled us to develop solutions with rheological behavior analogous to real whole blood and with a refractive index suited for PDMS (polydymethylsiloxane) micro- and milli-channels. In addition, these blood analogues can be modified in order to obtain a larger range of refractive indices from 1.38 to 1.43 to match the refractive index of several materials other than PDMS.
血液的非牛顿特性非常重要，因为它们与心血管疾病的发生密切相关。因此，通过人体循环系统的主要血管对血液动力学有很好的了解，对于这些疾病的检测，特别是治疗，是非常重要的。为了方便和更好地控制流动，这些研究通常在体外进行，而这通常需要血液模拟溶液，这些溶液不仅要充分模拟血液的粘弹性，还要最大限度地减少由于血管弯曲而产生的不良光学扭曲，这可能会干扰流动可视化或粒子图像测速测量。在这项工作中，我们通过被动微流变实验得到了全血的粘弹性模量。这些结果以及文献中现有的全血剪切和拉伸流变数据，使我们能够开发出具有类似于真实全血的流变行为的溶液，并且折射率适合 PDMS（聚二甲基硅氧烷）微通道和毫通道。此外，这些血液模拟物可以进行修改，以便获得从 1.38 到 1.43 的更大折射率范围，以匹配除 PDMS 以外的几种材料的折射率。
