美国纽约大学Stefano Sacanna、芝加哥大学William T. M. Irvine等研究人员合作实现无机胶体细胞模拟物中的跨膜运输。相关论文于2021年9月8日发表在《自然》杂志上。

研究人员报道了微胶囊的创造，它可以通过简单的全局变量（光照和pH值）使其失去平衡，从而捕获、浓缩、储存和提供一般的微观有效载荷。这项设计没有从生物学中借用任何材料，而是使用空心胶体作为球形细胞膜的模拟物，并具有明确定义的单微孔。精确可调的单分散胶囊是合成自我膨胀机制的结果，可以大量生产。

在中空单元内，一个可光开关的催化剂产生了一个化学梯度，通过膜的微孔传播到外部，并将目标物体泵入细胞内，作为一个浮力牵引束。由微孔的几何形状带来的熵能屏障即使在催化剂关闭时也能保留货物。这项发现为开发下一代智能材料、自主微机械和人工细胞模拟提供了蓝图。

据介绍，活细胞的一个关键方面是它们能够从环境中获取能量，并利用它将特定的原子和分子物种送入和送出它们的系统，通常是在不利的浓度梯度下。主动运输使细胞能够储存代谢能量，提取废物，并在亚微米尺度上为细胞器提供基本构件。与活细胞不同的是，非生物系统没有可以专门激活的精细生化机器，从而精确控制生物物质。

附：英文原文

Title: Transmembrane transport in inorganic colloidal cell-mimics

Author: Xu, Zhe, Hueckel, Theodore, Irvine, William T. M., Sacanna, Stefano

Issue&Volume: 2021-09-08

Abstract: A key aspect of living cells is their ability to harvest energy from the environment and use it to pump specific atomic and molecular species in and out of their system—typically against an unfavourable concentration gradient1. Active transport allows cells to store metabolic energy, extract waste and supply organelles with basic building blocks at the submicrometre scale. Unlike living cells, abiotic systems do not have the delicate biochemical machinery that can be specifically activated to precisely control biological matter2,3,4,5. Here we report the creation of microcapsules that can be brought out of equilibrium by simple global variables (illumination and pH), to capture, concentrate, store and deliver generic microscopic payloads. Borrowing no materials from biology, our design uses hollow colloids serving as spherical cell-membrane mimics, with a well-defined single micropore. Precisely tunable monodisperse capsules are the result of a synthetic self-inflation mechanism and can be produced in bulk quantities. Inside the hollow unit, a photoswitchable catalyst6 produces a chemical gradient that propagates to the exterior through the membrane’s micropore and pumps target objects into the cell, acting as a phoretic tractor beam7. An entropic energy barrier8,9 brought about by the micropore’s geometry retains the cargo even when the catalyst is switched off. Delivery is accomplished on demand by reversing the sign of the phoretic interaction. Our findings provide a blueprint for developing the next generation of smart materials, autonomous micromachinery and artificial cell-mimics.

DOI: 10.1038/s41586-021-03774-y

Source: https://www.nature.com/articles/s41586-021-03774-y