Collaborative Research: Chiral objects in microfluidic shear flows: chiral separation and microbial locomotion

本项目研究手性粒子和手性生物在剪切流动中的动力学，采用微流体实验和数学建模相结合的方法。手性粒子是具有不能与其镜像重叠的形状的粒子，在基础科学和技术领域都具有广泛的兴趣。手性粒子在生物学中无处不在：例如，氨基酸就是手性分子。由于生命过程中涉及的分子间反应取决于参与分子的几何形状，手性药物、信息素、杀虫剂和气味剂的事件对映体都有变化&amp；事件生物学的影响。因此，人们对设计从两种对映体的混合物中分离纯对映体样品的方法非常感兴趣。此外，在生物学中，手性不仅发生在分子尺度上，也发生在细胞尺度上。许多游动的微生物具有手性螺旋结构，例如产生推进力的微生物。大多数细菌的Agella。与此同时，微生物的水环境不断受到&amp；#64258；uid和# 64258;哦，因此剪切，如在海洋，地下水，工业管道&amp；#64258；哦，还有导尿管。该项目有两个具体目标：(i)利用剪切中粒子的手性相关运动；如何在显微镜下用手性分离对映体混合物（ii）了解微生物的手性形态如何他们游泳和觅食。这些目标是：最终目标是更好地理解手性粒子在剪切中的行为。，因此适用于相同的实验和理论研究工具。拟议的研究具有以下潜力：(i)通过开发一种比目前可用的更简单、更便宜的分离策略，改变我们将外消旋混合物分离成组分对映体的技术能力；（ii）提高我们对微生物运动的理解，其应用范围从自然系统中限制元素的再循环到疾病和生物的传播；lm的形成。

This project investigates the dynamics of chiral particles and chiral organisms in shear flows, using a combination of microfluidic experiments and mathematical modeling. Chiral particles are particles with shapes that cannot be superimposed upon their mirror images, and are of broad interest for both basic science and technology. Chiral particles are ubiquitous in biology: for example, amino acids are chiral molecules. Since the intermolecular reactions involved in life processes depend on the geometry of participating molecules, different enantiomers of chiral drugs, pheromones, pesticides, and odorants have different biological effects. As a consequence, there is much interest in devising ways to separate pure enantiomeric samples out of a mixture of both enantiomers. Furthermore, in biology chirality occurs not only at the molecular scale, but also at the cellular scale. Many swimming microorganisms have chiral helical structures, such as the propulsion-generating flagella of most bacteria. At the same time, the watery environments of microbes are constantly subject to fluid flow, and hence shear, such as in the oceans, groundwater, industrial pipe flow, and catheters. This project has two specific aims: (i) exploiting the chirality-dependent motion of particles in shear flows to separate a mixture of enantiomers by handedness in a microfluidic channel, and (ii) understanding how chiral morphologies of microbes affect their swimming and foraging. These aims are unified by the ultimate goal of better understanding the behavior of chiral particles in shear flows, and hence amenable to the same experimental and theoretical research tools. The proposed research has the potential to (i) transform our technological capability to separate a racemic mixture into component enantiomers, by developing a simpler and less expensive separation strategy than those currently available, and (ii) improve our understanding of microbial motility, with applications ranging from the recycling of limiting elements in natural systems to the spreading of disease and biofilm formation.