Modular surface chemistry of green nanoparticles for the next generation of functional materials

本课题旨在调整绿色纳米颗粒（gNPs）的界面特性，以开发下一代功能微/纳米结构材料。对环境可持续性的需求使得可再生材料成为未来消费品发展的关键。植物来源的纳米晶体（如纤维素纳米晶体- CNCs）特别有吸引力，因为它们具有独特的性质，可以产生新材料。然而，gNPs广泛使用的一个关键障碍是它们缺乏反应性。虽然存在许多功能化gNPs的方法，但它们都很昂贵，需要严格的处理，或者限制了功能的多样性。这严重阻碍了国民生产总值在消费品中的使用。最近，我们的团队提出使用三嗪基化学对纳米纤维素进行模块化功能化，并表明其界面特性可以很容易地定制。这种化学的主要优点是反应在温和的条件下进行，功能化效率高，试剂价格便宜。当前的挑战，这一建议解决，是扩大功能的范围，可以引入到gNPs。我们将通过创建一个三嗪基衍生物库来实现这一目标，这些衍生物将接枝到可再生来源的gNPs上，使它们具有功能性，活性性和/或与各种溶剂兼容。这些新的gNPs将成为开发新材料和新产品的平台。我们将使用修改的gNPs来开发绿色光聚合3D打印生物墨水，具有可调的机械性能和孔隙率，并且可以在打印后进行修改，以空间和时间控制的方式纳入生化图案。使用这种生物墨水生产的3D打印支架将测试其在细胞培养和组织工程中的适用性。我们还将使用改性纳米材料来开发能够吸收污染物或释放药物的超多孔微粒。这将通过使用具有两种功能的gNPs来实现：一方面，互补反应基团将促进有效的交联，另一方面，结合部分将允许清除重金属或缓慢释放抗菌剂。最后，我们将使用三嗪基化学来开发一种反应性纸张平台，使制造复杂的基于纸张的微分析或电子设备成为可能。这将通过在纸上安装反应基团来实现，使我们能够直接打印和共价固定各种小分子，聚合物，肽和纳米颗粒，并展示打印功能在传感设备制造中的使用。拟议的研究，包括有机合成、表征和制造，以及与工业合作伙伴的互动，将为学员提供丰富的多学科环境和高度可转移的化学、材料科学、微/纳米技术和知识转化技能。

This proposal aims to tune the interfacial properties of green nanoparticles (gNPs) to develop the next generation of functional micro/nanostructured materials. The demand for environmental sustainability makes renewable materials key to the development of future consumer products. Plant-derived NPs (e.g, cellulose nanocrystals - CNCs) are especially attractive because they have unique properties that can lead to new materials. However, a key obstacle to the widespread use of gNPs is their lack of reactivity. While many approaches to functionalize gNPs exist, they are expensive, require harsh processing, or limit functional diversity. This has severely hindered the use of gNPs in consumer products. Recently, our group proposed to use triazinyl chemistry for the modular functionalization of nanocellulose and showed that its interfacial properties can be readily tailored. Key advantages of this chemistry are that the reactions are done in mild conditions, the functionalization is efficient, and the reagents are inexpensive. The current challenge, which this proposal addresses, is to expand the range of functionalities that can be introduced onto gNPs. We will accomplish this by creating a library of triazinyl derivatives that will be grafted onto renewably-sourced gNPs, rendering them functional, reactive, and/or compatible with a variety of solvents. These new gNPs will be a platform for the development of new materials and products. We will use modified gNPs to develop green photopolymerizable 3D printing bioinks that have tuneable mechanical properties and porosity, and that can be modified post-printing to incorporate biochemical motifs in a spatially and temporally controlled way. 3D printed scaffolds produced using such bioinks will be tested for their suitability in cell culture and tissue engineering. We will also use modified nanomaterials to develop ultraporous microparticles capable of absorbing contaminants or releasing drugs. This will be accomplished by using gNPs bearing two functionalities: on one hand, complementary reactive groups will promote efficient crosslinking, and on the other, binding moieties will allow scavenging heavy metals or slowly releasing antimicrobial agents. Finally, we will use triazinyl chemistry to develop a reactive paper platform that enables the fabrication of complex paper-based microanalytical or electronic devices. This will be done by installing reactive groups on paper that allow us to directly print and covalently immobilize a variety of small molecules, polymers, peptides and nanoparticles, and demonstrating the use of the printed functionalities in the fabrication of sensing devices. The proposed research, including organic synthesis, characterization, and fabrication, and interactions with industrial partners, will provide trainees a rich multidisciplinary environment and highly transferrable skills in chemistry, materials science, micro/nanotechnology, and knowledge translation.