Zentralinstitut für Medizintechnik, Technische Universität München , Boltzmannstrasse 11, 85748 Garching, Germany.
Langmuir. 2013 Dec 23;29(51):15965-73. doi: 10.1021/la404016y. Epub 2013 Dec 12.
The diffusion of colloids in complex biological hydrogels is regulated by a broad range of factors including geometric constraints and different types of physical interactions between the particles and the hydrogel constituents. As a consequence, the particle mobility depends not only on the hydrogel microarchitecture but also on the detailed chemical composition of the hydrogel solvent. Here, we employ single particle tracking techniques to quantify the diffusion behavior of submicrometer-sized particles in such a biological hydrogel. We observe three states of colloid mobility: free diffusion, tightly and weakly bound particles, and transitions between those states. Finally, by comparing the efficiency of particle trapping in Matrigel as a function of the ionic strength of the hydrogel buffer, we show that ion-specific effects regulate the efficiency of this trapping process.
胶体在复杂生物水凝胶中的扩散受到多种因素的调节，包括几何约束以及颗粒与水凝胶成分之间的不同类型的物理相互作用。因此，颗粒的迁移率不仅取决于水凝胶的微观结构，还取决于水凝胶溶剂的详细化学成分。在这里，我们采用单颗粒跟踪技术来定量研究亚微米级颗粒在这种生物水凝胶中的扩散行为。我们观察到胶体迁移率的三种状态：自由扩散、紧密结合和弱结合的颗粒，以及这些状态之间的转变。最后，通过比较粒子在 Matrigel 中的捕获效率与水凝胶缓冲液的离子强度的关系，我们表明离子特异性效应对这种捕获过程的效率进行了调节。
