CAREER: Rheology, Stability, and Sudden Collapse of Colloidal Gels: A Micromechanical Study

主要研究者：Zia，Roseanna N.提案编号：1351184本CAREER提案的目标是通过发现和阐明胶体凝胶突然崩溃的潜在机制来开发凝胶稳定性的预测理论。这些研究对于合理设计软生物材料，如可注射药物输送平台和可移植组织支架给身体不能产生这种组织的患者非常重要。这种理论的发展是潜在的变革，因为它将建立定性的理解凝胶collaps.Injectable凝胶已经出现在过去的十年间，作为一个首要的工具，在组织工程和药物输送由于其生物相容性，可调不同的治疗部分，和微创输送。然而，这种凝胶容易突然失效？支架会毫无预兆地坍塌成致密的无结构沉积物。在这种情况下，活性化合物的转运被显著地减少，并且支架样结构支撑被丧失。目前还不能预测的凝胶崩溃，由于崩溃的详细观察，模拟大规模的凝胶演变的计算费用，和有限的理论被捕胶体动力学的困难。这项研究将创建一个窗口，通过它可以查看粒子和网络重排的精确细节，实时崩溃，因为它发生了。这将产生一个相位图，第一次预测崩溃和特征长度规模，年龄，吸引力和导致崩溃的潜在力量。

PI: Zia, Roseanna N.Proposal Number: 1351184The goal of this CAREER proposal is to develop a predictive theory for gel stability by discovering and elucidating the underlying mechanisms of the sudden collapse of colloidal gels. Such research is important for the rational design of soft biomaterials, such as injectable drug delivery platforms and transplantable tissue scaffolds to patients whose body cannot generate such tissue. The development of such theory is potentially transformative, because it would establish qualitative understanding of gel collapse.Injectable gels have emerged in the past decade as a premier tool in tissue engineering and drug delivery due to their biocompatibility, tunability to different therapeutic moieties, and minimally invasive delivery. However, such gels are susceptible to sudden failure ? without warning the scaffold collapses into a dense, structureless sediment. In that case, the transport of active compounds is dramatically curtailed, and the scaffold-like structural support is lost. It is not currently possible to predict gel collapse owing to the difficulty of detailed observation of collapse, the computational expense of simulating large-scale gel evolution, and limited theory of arrested colloidal dynamics. This study will create a window through which to view, in exacting detail of particle and network rearrangements, the real-time collapse, as it occurs. This will yield a phase map that, for the first time, predicts the collapse and the characteristic length scale, age, attraction and underlying forces that lead to collapse.