Green Chemistry Approach in Developing Polymeric Biomaterials

鉴于环境保护和能源消耗的重要性和日益受到关注，生物技术是未来化学工业和可持续发展的关键。我们采用绿色化学方法制备生物相容性材料来解决相关问题。(1)新的生物材料。生物相容性对于用于与人体接触的生物医学和制药应用的聚合物很重要。为了解决这个问题，我们使用来自生物来源的天然化合物（胆汁酸，碳水化合物，氨基酸）设计和合成各种聚合物，包括可降解聚合物，刺激响应材料，自修复水凝胶。聚合物将被表征和测试其预期应用，包括软组织和硬组织工程，药物输送和细胞培养。生物功能基团将被引入聚合物中，用于分子和细胞识别，靶向药物输送以及生物传感器的设计和测试。将研究材料的生物相容性和毒性。(2)聚合物的合成和改性将发展绿色化学方法。酶将用于转化已经附着在聚合物链上的生物分子，以产生具有新特性的官能团。例如，将测试葡萄糖氧化酶以将连接在我们的含糖聚合物上的碳水化合物侧基转化为酸基。这种共聚物可以是pH响应性的，并且带电荷的羧基也将促进骨再生所需的生物矿化。我们的初步结果是令人鼓舞的，我们将研究酶在聚合物上转化不同底物的效率。酶如腈水合酶、腈水解酶和酰胺酶将用于将腈基转化为酰胺基，然后转化为酸基，从而简化了共聚物的合成程序，并避免了使用金属催化剂和严格的反应条件。这些聚合物的热响应性和溶液性质将被研究，以探索其作为絮凝剂和流变改性剂的应用。(3)分子水凝胶化。胆汁酸衍生物可以通过超分子组装形成分子水凝胶。我们已经证明，通过分子相互作用实现的边际溶解度是小分子凝胶化的条件。我们将试图阐明水凝胶化过程的指导原则。将研究凝胶的流变学和机械性能，并测试其在细胞培养和软组织工程中的应用。总之，拟议的研究工作具有基础和实际意义，将导致创新技术和新的功能材料用于生物医学和工业应用。它是多学科的性质，将提供一个理想的培训环境，为年轻的高素质人才。

Given the importance and growing concerns of environmental protection and energy consumption, biotechnology holds the key for chemical industry and sustainable development in the future. We use green chemistry approaches to make biocompatible materials to solve related problems. (1) New biomaterials. Biocompatibility is important for polymers used for biomedical and pharmaceutical applications in contact with the human body. To address this issue, we use natural compounds (bile acids, carbohydrates, amino acids) from biological sources in the design and synthesis of a variety of polymers, including degradable polymers, stimuli-responsive materials, self-healing hydrogels. The polymers will be characterized and tested for their intended applications including soft and hard tissue engineering, drug delivery and cell culture. Bio-functional groups will be introduced in the polymers for molecular and cellular recognition in targeted delivery of drugs and for the design and tests of biosensors. The biocompatibility and toxicity of the materials will be studied. (2) Green chemistry methods will be developed for the synthesis and modification of polymers. Enzymes will be used in the transformation of the biomolecules already attached on a polymer chain to produce functional groups with new properties. For example, glucose oxidase will be tested to convert the carbohydrate side groups attached on our sugar-containing polymers into acid groups. Such a copolymer may be pH-responsive, and the charged carboxylic group will also facilitate biomineralization needed for bone regeneration. Our preliminary results are encouraging, and we will study the efficiency of enzymes in the transformation of the different substrates on the polymers. Enzymes such as nitrile hydratase, nitrilase and amidase will be used in the transformation of the nitrile groups into amide and then into acid groups, thereby simplifying the synthetic procedure of copolymers and avoiding the use of metal catalysts and stringent reaction conditions. The thermoresponsiveness and solution properties of these polymers will be studied to explore their applications as flocculants and rheology-modifiers. (3) Molecular hydrogelation. Bile acid derivatives are found to form molecular hydrogels through supramolecular assembly. We have demonstrated that a marginal solubility achieved through molecular interactions is a condition for the gelation of small molecules. We will try to elucidate the principles guiding the hydrogelation process. The rheological and mechanical properties of the gels will be studied and their use in cell culture and soft-tissue engineering will be tested. In summary, the proposed research work is of both fundamental and practical importance and will lead to innovative technology and new functional materials for biomedical and industrial applications. It is multi-disciplinary in nature and will provide an ideal training environment for young highly qualified personnel.