由“可逆氧化还原响应性”操控膜结构的原始细胞微囊

Redox reaction is the fundamental of energy transport and molecular synthesis in biological process. Therefore, the synthetic protocells in which the “cell membranes” can participate reversibly into the redox reaction will play a crucial role in biomimetic synthesis and delivery of biological molecules. However, there was few report related to the development of the protocell-like microcapsules with redox responsive membrane. We developed protocell-like colloidosomes with membrane-extendable property based on the liquid/liquid higher-order assembly of crystalline polyferrocenylsilane (PFS) cylindrical micelles. But in the previous case, the ferrocene-containing moiety did not demonstrate its redox response due to their location inside the crystalline micellar core. On this basis, herein we design and synthesize a hydrophilic carboxyl-containing PFS homo-polymer, and propose the approach as follows based on the interfacial self-assembly of the PFS homo-polymer to construct protocell-like microcapsules with redox responsive membrane. The research in this proposal includes three parts as follows. (1) The general idea is to construct the microcapsule with redox responsive membrane from the liquid/liquid interfacial self-assembly of the hydrophilic PFS macromolecules. The mechanism related to the formation of PFS microcapsules and the interfacial self-assembly of PFS macromolecules will be studied systematically. (2) Based on the successful fabrication of these redox responsive PFS microcapsules, we are going to study the encapsulation and controlled release of various biomolecules by using these PFS microcapsules, and demonstrate the crucial role played by these microcapsules in biomimetic synthesis and biomolecule delivery. (3) Finally, several typical living cells will be chosen to study their interaction and signaling with PFS-based protocells. Basically, this study will develop an interfacial self-assembly approach to construct novel PFS-based protocells with redox responsive membranes, and study their encapsulation and delivery capability to biomolecules after elucidating the relationship between the structure and properties of microcapsules.

氧化还原反应是生命过程中能量转运与物质合成的基础，因而，膜结构能够可逆参与氧化还原反应的原始细胞微囊无疑对于生命物质的合成与输运具有重要意义。但迄今，具有此特点的原始细胞微囊仍未见报道。我们前期利用聚二茂铁硅烷结晶性胶束的液/液界面组装构筑了具有外延生长特点的结晶性仿细胞微囊，但由于二茂铁组分位于结晶性胶束内核而使得这类微囊无法发挥其氧化还原响应性。基于此，本研究设计了一种水溶性含羧基聚二茂铁硅烷(PFS)均聚物，拟利用如下思路构筑氧化还原响应的原始细胞微囊。(1)利用这类PFS大分子的液/液界面组装构筑具备氧化还原响应膜的原始细胞微囊，并研究界面组装与微囊形成的机理。(2)利用这类原始细胞微囊包封各类生物分子，探讨聚二茂铁硅烷“细胞”膜的氧化还原响应性，利用此特点研究微囊在生命物质合成与输运中的关键作用。(3)开展原始细胞与天然细胞间的相互作用及高层级组装行为研究，为其生物应用奠定基础。

氧化还原反应是生命过程中能量转运与物质合成的基础，因而，膜结构能够可逆参与氧化还原反应的原始细胞微囊无疑对于生命物质的合成与输运具有重要意义。但迄今，具有此特点的原始细胞微囊仍未见报道。基于此，本项目设计并了一种水溶性含羧基聚二茂铁硅烷均聚物(PFS-COOH)，使其在特定的油包水乳液环境下能够发生界面自组装，利用如下思路构筑了氧化还原响应的原始细胞微囊。具体工作如下。(1)利用这类PFS-COOH大分子的液/液界面组装构筑具备氧化还原响应膜的原始细胞微囊，并研究界面组装与微囊形成的机理。(2)利用这类原始细胞微囊包封各类生物分子，系统探讨了聚二茂铁硅烷“细胞”膜的氧化还原响应性，利用此特点研究了微囊在生命物质合成与输运中的关键作用。(3)系统开展了原始细胞与天然细胞间的相互作用及高层级组装行为研究，包括原始细胞微囊在原位催化纳米颗粒、细胞内吞行为、酶输运、肿瘤光热治疗等一系列领域的应用，为其生物应用奠定了基础。