Hao Xiang, Sang Wei, Hu Jun, Yan Qiang
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China.
State Key Lab of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
ACS Macro Lett. 2017 Oct 17;6(10):1151-1155. doi: 10.1021/acsmacrolett.7b00649. Epub 2017 Oct 4.
Energy dissipation underlies dynamic behaviors of the life system. This principle of biology is explicit, but its in vitro mimic is very challenging. Here we use an energy-dissipative self-assembly pathway to create a life-like polymer micellar system that can do periodic and self-adaptive pulsating motion fueled by cell energy currency, adenosine triphosphate (ATP). Such a micelle expansion-contraction behavior relies on transient supramolecular interactions between the micelle and ATP fuel. The micelles capturing ATPs will deviate away from the thermodynamic equilibrium state, driving a continuous micellar expansion that temporarily breaks the amphiphilic balance, until a competing ATP hydrolysis consumes energy to result in an opposing micellar contraction. As long as ATP energy is supplied to keep the system in out-of-equilibrium, this reciprocating process can be sustained, and the ATP level can orchestrate the rhythm and amplitude of nanoparticulate pulsation. The man-made assemblies provide a model for imitating biologically time-dependent self-assembly and periodic nanocarriers for programmed drug delivery.
能量耗散是生命系统动态行为的基础。这一生物学原理是明确的，但其体外模拟极具挑战性。在此，我们利用能量耗散自组装途径创建了一种逼真的聚合物胶束系统，该系统能够进行由细胞能量货币三磷酸腺苷（ATP）驱动的周期性和自适应脉动运动。这种胶束的膨胀-收缩行为依赖于胶束与ATP燃料之间的瞬态超分子相互作用。捕获ATP的胶束将偏离热力学平衡状态，驱动胶束持续膨胀，暂时打破两亲平衡，直到竞争性的ATP水解消耗能量导致相反的胶束收缩。只要供应ATP能量以保持系统处于非平衡状态，这个往复过程就可以持续，并且ATP水平可以协调纳米颗粒脉动的节奏和幅度。这些人造组件为模仿生物时间依赖性自组装提供了一个模型，并为程序化药物递送提供了周期性纳米载体。
