Biomicrofluidics. 2009 Jan 5;3(1):12006. doi: 10.1063/1.3067820.
Living cells are a fascinating demonstration of nature's most intricate and well-coordinated micromechanical objects. They crawl, spread, contract, and relax-thus performing a multitude of complex mechanical functions. Alternatively, they also respond to physical and chemical cues that lead to remodeling of the cytoskeleton. To understand this intricate coupling between mechanical properties, mechanical function and force-induced biochemical signaling requires tools that are capable of both controlling and manipulating the cell microenvironment and measuring the resulting mechanical response. In this review, the power of microfluidics as a functional tool for research in cell mechanics is highlighted. In particular, current literature is discussed to show that microfluidics powered by soft lithographic techniques offers the following capabilities that are of significance for understanding the mechanical behavior of cells: (i) Microfluidics enables the creation of in vitro models of physiological environments in which cell mechanics can be probed. (ii) Microfluidics is an excellent means to deliver physical cues that affect cell mechanics, such as cell shape, fluid flow, substrate topography, and stiffness. (iii) Microfluidics can also expose cells to chemical cues, such as growth factors and drugs, which alter their mechanical behavior. Moreover, these chemical cues can be delivered either at the whole cell or subcellular level. (iv) Microfluidic devices offer the possibility of measuring the intrinsic mechanical properties of cells in a high throughput fashion. (v) Finally, microfluidic methods provide exquisite control over drop size, generation, and manipulation. As a result, droplets are being increasingly used to control the physicochemical environment of cells and as biomimetic analogs of living cells. These powerful attributes of microfluidics should further stimulate novel means of investigating the link between physicochemical cues and the biomechanical response of cells. Insights from such studies will have implications in areas such as drug delivery, medicine, tissue engineering, and biomedical diagnostics.
活细胞是自然界最复杂和协调的微观机械物体的精彩展示。它们爬行、扩散、收缩和放松，从而执行多种复杂的机械功能。或者，它们也会对物理和化学线索做出反应，导致细胞骨架的重塑。要理解这种机械特性、机械功能和力诱导生化信号之间的复杂耦合，需要能够控制和操纵细胞微环境并测量由此产生的机械响应的工具。在这篇综述中，强调了微流控作为细胞力学研究的功能工具的强大功能。特别是，讨论了当前的文献，以表明基于软光刻技术的微流控具有以下能力，对于理解细胞的机械行为具有重要意义：（i）微流控能够创建体外模型的生理环境，在这些环境中可以探测细胞力学。（ii）微流控是传递影响细胞力学的物理线索的绝佳手段，例如细胞形状、流体流动、基底形貌和刚度。（iii）微流控还可以使细胞暴露于化学线索，例如生长因子和药物，这些线索会改变它们的机械行为。此外，这些化学线索可以在整个细胞或亚细胞水平上传递。（iv）微流控设备能够以高通量的方式测量细胞的固有机械特性。（v）最后，微流控方法提供了对液滴大小、生成和操纵的精确控制。结果，液滴越来越多地被用于控制细胞的物理化学环境，并作为活细胞的仿生模拟物。微流控的这些强大属性应该进一步刺激研究物理化学线索与细胞生物力学响应之间联系的新方法。这些研究的见解将对药物输送、医学、组织工程和生物医学诊断等领域产生影响。
