Light-induced artificial blood vessels for investigating cardiovascular systems

Flow properties of blood play a significant role in the cardiovascular systems containing arteries, veins and capillaries. Changes of these flow properties lead to abnormal tissue diffusion and thus to problems in, e.g., oxygen transport. Deeper understanding of the way flow is developed in these vessels is thus key to the understanding of many diseases and of high relevance for biomedical research. We have developed a highly flexible PDMS work station that offers the possibility to model different in vivo geometries for in vitro studies. Since PDMS is a low cost, bio-compatible, and transparent polymer, it is well suited for lab-on-a-chip applications. In addition to modelling vascular geometries, blood properties have to be modelled as well. Blood-like suspensions as well as the impact of the Fåhræus–Lindqvist effect are considered. With a combination of Particle Image Velocimetry (PIV) and Particle Tracking Algorithms (PTA) flow profiles within these models are analyzed and discussed. Furthermore, we explore the combination of these technologies with holographic optical tweezers (HOT) to determine forces acting on flow tracers.