Exploring new frontiers of colloidal science: active colloids

活性胶体颗粒是能够在流体中自推进的微米/纳米尺寸的颗粒。它们的“游泳”能力使它们对新技术应用很感兴趣，从用于药物递送的货物颗粒到模型悬浮液，以综合地重建生物系统的行为。它们也可能表现出集体运动，类似于自然界中常见的现象，从细菌菌落中的群集现象到鸟群或鱼群。 这些合成粒子有可能彻底改变许多医学上的常见程序。例如，它们逆着血流游动的能力可用于将治疗剂输送到伤口中以阻止出血，或者它们可以穿过胃肠道并到达在没有侵入性手术的情况下固有地难以击中的位置。此外，活性胶体将被用作设计新的“活性”复合材料的构建块。由于其组成元素（活性颗粒）的运动，这些新型复合材料将能够响应外部刺激并动态改变其机械、热和电性能。 受这些独特的可能性的激励，该研究计划旨在（1）进一步发展活性胶体领域的基础知识，（2）利用活性胶体的独特性质，基于活性胶体和复杂流体的组合生成新材料。 在我们的研究小组中，我们将合成活性胶体颗粒，研究它们在复杂流体中的动力学，以深入了解它们在生物流体中的行为（如粘液，唾液或血液，它们具有固有的粘弹性），并最终设计/开发新的多功能复合材料。我们的研究结果将有助于我们设计新的解决方案来控制活性胶体的运动方向，提高它们的游泳速度和效率。此外，还将大力完成目前可以实现的药物输送应用的步骤。 最后，参与这项研究计划的人员将接受最先进技术的培训，他们将获得跨学科的科学知识，这将使他们成为加拿大和国际科学界的强大资产。这将使他们能够响应我们社会的科学和技术需求，并具体化更好的解决方案，以改善我们的日常生活质量。

Active colloidal particles are micro/nano sized particles which are able to self-propel in fluids. Their ability to “swim” makes them interesting for new technological applications ranging from cargo particles for drug delivery to model suspensions to recreate synthetically the behaviour of biological systems. They may also display collective motion, similar to that commonly seen in nature, from swarming phenomena in bacterial colonies to flocks of birds or fish. These synthetic particles hold potential to revolutionize many common procedures applied in medicine. For example, their ability to swim against blood flow can be used to delivery therapeutics into wounds to halt hemorrhage or they can travel through the gastrointestinal tract and reach locations which are inherently difficult to hit without invasive surgeries. Furthermore, active colloids will be used as building blocks in designing new “active” composites. Thanks to the movement of their constitutive elements (the active particles), these new composites will be able to respond to external stimuli and change their mechanical, thermal and electrical properties on-the-fly. Motivated by these unique possibilities, this research program aims to (1) further develop fundamental knowledge in the field of active colloids and (2) exploit the unique properties of active colloids in generating new materials based on the combination of active colloids and complex fluids. In our research group, we will synthetize active colloidal particles, study their dynamics in complex fluids to gain insights into their behaviour in biological fluids (such as mucus, saliva or blood which are inherently viscoelastic) and finally design/develop new multi-functional composites. The results of our investigations will help us to engineer new solutions to control active colloids' direction of motion and improve their swimming speed and efficiency. Furthermore, a strong effort will be dedicated to completing the step towards drug-delivery applications that are currently within reach. Finally, the personnel involved in this research program will receive training on state-of-art technologies and they will acquire interdisciplinary scientific knowledge which will make them strong assets for the Canadian and International scientific community. This will enable them to respond to the scientific and technological needs of our society and to concretize better solutions to improve our daily quality of life.