Cerium oxide particles as functional haloperoxidase mimics to combat biofouling

氧化铈颗粒作为功能性卤过氧化物酶模拟物来对抗生物污垢

• 批准号: 405861793
• 负责人: Professor Dr. Thomas Ternes
• 金额: --
• 依托单位: Bundesanstalt für Gewässerkunde (BfG)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/405861793?language=en
• 关键词: Cerium; oxide; particles; functional; haloperoxidase

Surfaces in aqueous habitats are usually colonized by microorganisms. A textbook example is the settlement of bacteria, unicellular organisms, algae or shells on ships or port facilities. A current strategy to reduce this so-called biofouling is the addition biocides in paints. Microorganisms enter into synergistic communities in the formation of biofilms and co-ordinate film formation through signaling via signaling molecules ("quorum sensing"). A defense mechanism of marine organisms is based on disrupting cell-to-cell communication of epibionts by enzymatic formation of halogenated - and thus ineffective - signaling molecules. The proposed project uses CeO2-x nanoparticle (NP) enzyme (haloperoxidase) mimics, which - analogously to natural haloperoxidases - catalyze the oxidation of ubiquitous halides by hydrogen peroxide (generated in daylight). The resulting hypohalous acid (HOX) intermediates react with organic substrates in follow-up to form the halogenated signal molecules. The metal oxide particles can be immobilized on surfaces as a constituent of paints and resins without losing their effect. The catalytic halogenation of a halogenated signal compound has been demonstrated in laboratory experiments. The project aims to achieve the following objectives by pooling the expertise of both project partners:1. Unraveling the sequence of the halogenation reactions: Does the reaction proceed via short-lived HOBr/HOCl intermediates, or are other reactive intermediates involved? Which halogenated signaling compounds are formed in natural waters (i.e., in the field)? What is the stability of these halogenated primary intermediates and in what concentrations are they formed? Which other compounds are formed?2. The catalytic activity of CeO2-x NP in halogenation reactions is determined by defects. By increasing the defect concentration in different solid state solution series (e.g., CeO2-M2O3, (M = La, Y, Bi, etc.) the activity should be improved.3. Alternative halogenation catalysts: Besides the halogenation properties of CeO2-x and its substituted variants, the halogenation activity of Ce perovskites (BaCe1-xO3-y etc.), Ce-substituted silica compounds (Ce-TUD-1), delafossite-type composites (CuCrO2-CeO2), or Mn oxides will be tested.4. The use of CeO2-x NP (and possible alternatives) in antifouling applications requires the availability in sufficient amounts. The synthesis must be scaled up to the kg scale.5. Analytical examination and optimization of the resistance of the coatings and their surface properties: The particles should be integrated into films or coatings for use under application oriented conditions. The surface properties must be optimized, the bacterial and algae growth on the films and the leaching of the particles (environmental compatibility) and the released products will be determined.

水栖息地中的表面通常由微生物定植。教科书的例子是在船舶或港口设施上的细菌，单细胞生物，藻类或贝壳的定居。当前减少这种所谓生物污染的策略是油漆中的添加杀菌剂。微生物通过信号分子（“ Quorum Sensing”）通过信号传导形成生物膜和辅入膜形成，进入协同群落。海洋生物的防御机制是基于通过酶形成卤代的酶形成（因此无效）信号分子来破坏表象的细胞对细胞通信。拟议的项目使用CEO2 -X纳米颗粒（NP）酶（卤代氧化酶）模拟物，类似于天然的卤代氧化酶 - 催化过氧化氢（在日光下产生）催化无处不在的卤化物的氧化。所得的低硅酸（HOX）中间体与随访中的有机底物反应，形成卤代信号分子。金属氧化物颗粒可以固定在表面上，作为油漆和树脂的组成，而不会失去其作用。在实验室实验中已经证明了卤代信号化合物的催化卤素化。该项目旨在通过汇总两个项目合作伙伴的专业知识来实现​​以下目标：1。阐明卤化反应的序列：反应是通过短暂的HOBR/HOCL中间体进行的，还是其他反应性中间体涉及？在天然水域（即在现场）形成哪种卤代信号化合物？这些卤代主要中间体的稳定性是什么？它们形成了什么浓度？形成了哪些其他化合物？2。 CEO2-X NP在卤化反应中的催化活性由缺陷确定。通过增加不同固态溶液序列中的缺陷浓度（例如CEO2-M2O3，（M = LA，Y，BI等），应改进活性。3。替代卤代催化剂：除了CEO2-X的卤化特性外（CE-TUD-1），Delafossite型复合材料（CUCRO2-CEO2）或Mn氧化物将测试。4。在面向应用条件下使用的薄膜或涂层必须优化表面特性，膜上的细菌和藻类生长以及颗粒的浸出（环境兼容性），并确定释放的产品。