基于短肽-卟啉复合凝胶微粒的共组装调控及在光合制氢方面的应用研究

Biological peptides, especially the short peptides with simply and easily programmable structures, have unique advantages in developing new materials. In this project, the photosensitizers, porphyrins, which have strong visible light absorption ability, are co-assembled with the short peptides to form hydrogel particles. Then the hydrogenases are immobilized into the hydrogel particles. With porphyrins as the light-harvesting units to produce photoelectrons, peptide-based hydrogel particles as the photoelectron conductors and hydrogenases as the photoelectron acceptors to catalyze the production of hydrogen, we build an artificial hydrogen photoproduction system. The connection among the co-assembly mechanism, driving forces and molecular structures will be studied and the structural effects of hydrogel particles on the light-harvesting, photoelectron production and transfer efficiency will also be studied to optimize the co-assembly of porphyrin and peptide. Subsequently we will investigate the abilities of the hydrogel particles in stimulating and maintaining hydrogenases’ bioactivities to product hydrogen. This project is of great importance in fabricating and optimizing the man-made green energy devices.

生物内源的肽，尤其是结构简单、可灵活设计的短肽，在新材料设计和开发方面具有独特的优势。本项目在肽分子自组装形成水凝胶的基础上，将对可见光有较强吸收的卟啉与短肽分子，通过物理化学方法共组装为具有捕光性能的导电凝胶微粒。同时将氢化酶固定在该凝胶微粒内：制备以卟啉为捕光分子，肽导电凝胶微粒为电子传递介质，氢化酶为电子受体和制氢中心的肽基绿色能源凝胶体系。通过调控组装条件和肽分子结构，研究卟啉与短肽分子共组装凝胶微粒的形成规律、驱动力以及与分子结构间的关系；研究凝胶微粒的微结构与其光电功能之间的关系，以实现卟啉-肽有序结构的可控组装和结构优化，提高凝胶微粒捕光效率和光电子的产生和传输效率。同时研究凝胶微粒对氢化酶活性的激发与保持能力及其光解水制氢的能力。本项目构筑的兼具光能捕获、光电子传输和催化制氢的肽基凝胶材料，在设计和优化人工光合制氢材料方面具有重大的理论和现实意义。

人工光合产氢是缓解能源危机的最有效的途径之一。本项目利用分子自组装技术制备短肽和卟啉共组装的凝胶微粒，并进一步将氢化酶固定在凝胶微粒内，得到以卟啉为捕光天线，肽自组装水凝胶微粒为电子传递介质，氢化酶为电子受体和制氢中心的人工光合产氢体系。本项目设计并合成了多种自组装形成水凝胶的短肽分子，研究了肽分子组装的机理及组装体结构与光电转化能力关系；进一步的探究了肽与卟啉分子共组装的形成水凝胶的条件，并研究了共组装水凝胶的光电转化效率与卟啉掺杂量的关系。本项目在设计和优化人工光合制氢材料方面具有重大的理论和现实意义。