Physics of biosensors and biocolloid transport in nature's own nanoenvironment

从物理学的角度来看，生物系统具有多组分性质、界面丰富和固有的非平衡性质。脂质是基本的组成部分，由于它们的两亲性，它们形成了细胞和周围环境等结构之间的界面。这些界面是功能性的：例如，蛋白质可以附着或穿透膜，从而为离子和大分子进出细胞提供运输通道。膜也能够融合而不失去其完整性。脂质膜是自然界自身的纳米环境。构建模块，脂质，以及许多功能单元，如纳米孔——离子通道和一些细菌毒素——都具有纳米尺度。本文利用计算物理和化学的方法研究了通道和纳米孔的相互作用和功能。目标有三个：首先，确定控制这些系统的基本物理相互作用和机制至关重要。其次，所获得的知识将用于研究新的纳米孔应用，如超灵敏纳米传感器和靶向药物递送。第三，存在方法论上的挑战。我们使用计算和理论分子模型和最先进的方法将使用和进一步发展。这里使用的方法适用于生物、材料和软物质物理和化学的许多其他问题，因此服务于广泛的社区。除了纳米孔，生物胶体，如囊泡也在研究中。其目的是研究如何利用电场操纵、运输、分离和识别生物胶体。与这些系统相关的物理现象非常普遍，其应用范围从癌细胞的分离到纳米马达和水样中毒素的检测。

From a physical point of view, biological systems can be characterized by their multicomponent nature, an abundance of interfaces and their inherent non-equilibrium nature. The basic building blocks are lipids, and due to their amphiphilic nature, they form interfaces between structures such as cells and their surroundings. These interfaces are functional: For example, proteins can attach to or penetrate through membranes, thus providing channels for transport of ions and larger molecules in and out of a cell. Membranes are also able to fuse without losing their integrity. The lipid membrane is nature's own nanoenvironment. The building blocks, lipids, as well as many of the functional units, such as nanopores - ion channels and some bacterial toxins -  have dimensions in the nanoscale. Here, the interactions and functionality of channels and nanopores are being investigated using the methods of computational physics and chemistry. The goal is threefold: First, it is vital to identify the fundamental physical interactions and mechanisms governing these systems. Second, the acquired knowledge will be used to study new nanopore applications such as ultrasensitive nanosensors and targeted drug delivery. Third, there are methodological challenges. We use computational and theoretical molecular modeling and state-of-the-art methods will used and developed further. The methods used here are applicable in many other problems in biological, materials and soft matter physics and chemistry, and thus serve a wide community. In addition to nanopores,  biocolloids, such as vesicles are being investigated. The aim is to study how biocolloids can be manipulated, transported, separated and identified using electric fields. The physical phenomena related to these systems are very general, and the applications range from separation of cancerous cells to nanomotors and detection of toxins in water samples.