Developing new assembly systems and new characterization method: face-rotating molecular polyhedra and micro-fluidic NMR technology

超分子化学是研究分子尺度之上、通过非共价或可逆共价相互作用形成分子组装体的科学，生命体系中的DNA、蛋白质等都是高度复杂、功能化的组装体。揭示组装基元间相互作用本质、组装过程物理化学性质和组装机理对理解生命体内组装行为、实现分子可控组装及其功能化具有重要意义。本论文分别从构建新组装体系和发展新表征方法两个角度开展工作，一方面采用新组装基元构建新组装体系——面方向性分子多面体，另一方面发展可用于表征复杂组装体系的原位表征方法——微流控核磁芯片技术。 第一部分工作借鉴了数学和生命体系中的面方向性多面体概念，设计合成了一系列具面方向性分子八面体，成功将面方向性构筑基元的二维手性传递至分子多面体的三...Supramolecular chemistry is defined as “chemistry beyond the molecule”, its main focus is molecular assemblies through non-covalent interactions or dynamic covalent bond. Those interactions are also essential in biological molecular assemblies such as DNA or protein, which exhibit sophisticated structures and functionalities. To give deep understanding of interactions, mimic structures and increas...学位：理学博士院系专业：化学化工学院_物理化学学号：2052014015395

3D-printed integrative probeheads for magnetic resonance

射频探头前端作为核磁共振设备的核心部件之一，极大程度的决定着系统实验性能的优劣。探头前端通常由射频线圈、射频电路及样品检测管道等部分组成。现有的射频线圈制作技术主要是通过手工或机械手段按照所需的线圈形状进行绕制。但是，当线圈结构较为复杂、不规则，或体积尺寸较小时，常规绕制方法便难以满足结构设计和制造的精度需求，因此造成线圈性能的劣化，增大检测区域的射频场不均匀性，对核磁共振检测产生负面影响。本研究中，利用3D打印熔融沉积制造或光敏树脂选择性固化技术精确加工出一体化磁共振探头前端，使用常温液态金属填充线圈模型管路形成射频线圈，搭建出稳定的一体化磁共振射频探头。利用高精度3D打印和液态金属灌注技术制备出包含有射频线圈和定制化样品管道结构在内的一体化磁共振射频探头前端，克服了传统磁共振三维微型线圈成型困难、与样品腔匹配程度差等问题，提高了探头的信噪比，为定制化的磁共振检测提供了新思路。 该工作由厦门大学电子科学与技术学院陈忠教授、游学秋副研究员和孙惠军高级工程师共同指导完成，博士研究生谢君尧为论文第一作者。厦门大学电子科学与技术学院黄玉清高级工程师、王忻昌副教授、倪祖荣助理教授、硕士研究生张德超，化学化工学院杨朝勇教授、博士研究生李星锐，萨本栋微米纳米科学技术研究院陈宏教授为合作作者。【Abstract】Magnetic resonance (MR) technology has been widely employed in scientific research, clinical diagnosis and geological survey. However, the fabrication of MR radio frequency probeheads still face difficulties in integration, customization and miniaturization. Here, we utilized 3D printing and liquid metal filling techniques to fabricate integrative radio frequency probeheads for MR experiments. The 3D-printed probehead with micrometer precision generally consists of liquid metal coils, customized sample chambers and radio frequency circuit interfaces. We screened different 3D printing materials and optimized the liquid metals by incorporating metal microparticles. The 3D-printed probeheads are capable of performing both routine and nonconventional MR experiments, including in situ electrochemical analysis, in situ reaction monitoring with continues-flow paramagnetic particles and ions separation, and small-sample MR imaging. Due to the flexibility and accuracy of 3D printing techniques, we can accurately obtain complicated coil geometries at the micrometer scale, shortening the fabrication timescale and extending the application scenarios.The work is supported by the National Natural Science Foundation of China (Grants U1632274, 11761141010, U1805261, 11475142, 22073078, and 61801411), and China Postdoctoral Science Foundation (2017M622075).研究工作得到国家自然科学基金、中国博士后科学基金等项目支持

Elucidation of the origin of chiral amplification in discrete molecular polyhedra

超分子自组装中的手性增强现象被广泛应用于偏光材料的构建、手性生物分子和手性药物分子的制备与分离，对相关领域有重要影响。然而受制于超分子体系在结构和成分上的复杂性，如何构建合理可靠的理论模型，从而理解其中手性传递的机理一直都是困扰化学研究者的难题之一。曹晓宇课题组以先前发展的笼状分子为基础，构建了一类全新的兼具手性和非手性顶点的手性笼状分子，为研究超分子组装中的手性传递提供了理想的平台。 该项工作由厦门大学曹晓宇教授和荷兰埃因霍芬理工大学的Albert J. Markvoort助理教授共同指导，王宇博士(厦门大学毕业，现为加州大学伯克利分校博士后)和厦门大学博士生房洪勋为共同第一作者，荷兰埃因霍芬理工大学的Ionut Tranca博士负责理论计算，厦门大学博士生瞿航和王忻昌负责单晶测试。此工作得到国内外众多学者的大力支持，特别感谢E. W. (Bert) Meijer教授促成了本次实验与理论的国际间合作，感谢Jean-Marie Lehn教授、张希教授、刘鸣华教授、程正迪教授、Takuzo Aida教授、江云宝教授、章慧教授、张维教授等对本工作的积极帮助与支持。【Abstract】Chiral amplification in molecular self-assembly has profound impact on the recognition and separation of chiroptical materials, biomolecules, and pharmaceuticals. An understanding of how to control this phenomenon is nonetheless restricted by the structural complexity in multicomponent self-assembling systems. Here, we create chiral octahedra incorporating a combination of chiral and achiral vertices and show that their discrete nature makes these octahedra an ideal platform for in-depth investigation of chiral transfer. Through the construction of dynamic combinatorial libraries, the unique possibility to separate and characterise each individual assembly type, density functional theory calculations, and a theoretical equilibrium model, we elucidate that a single chiral unit suffices to control all other units in an octahedron and how this local amplification combined with the distribution of distinct assembly types culminates in the observed overall chiral amplification in the system. Our combined experimental and theoretical strategy can be applied generally to quantify discrete multi-component self-assembling systems.This work is supported by the 973 Program (No. 2015CB856500), the NSFC (Nos. 21722304, 91427304, 21573181, 91227111 and 21102120), and the Fundamental Research Funds for the Central Universities (No.2 0720160050) of China.I.T. 研究工作得到科技部973计划（批准号：2015CB856500），国家自然科学基金委（批准号：21722304、91427304、 21573181、91227111、21102120）和中央高校基本科研业务费专项资金（批准号：20720160050）等项目支持