Biomolecular Mechanisms of Interaction between 2D Chalcogenide Materials and Environmentally-Relevant Biosystems

二维材料由具有确定的晶体结构和大的横向尺寸的原子级薄层组成。本项目的重点是二维过渡金属二硫属化物。 这些材料是在过去十年中出现的，由于其独特的光电性能，适用于现代计算，生物传感和通信以及物联网的广泛应用。虽然这些二维材料在负担得起的技术中有希望，但关于它们在与环境相关的生物系统的界面处的行为知之甚少。该项目将研究二维纳米材料与哺乳动物细胞相互作用的行为，重点关注三个不同的方面：细胞摄取机制;哺乳动物细胞中纳米材料的潜在结构转变;以及细胞环境中的反应性，特别是了解任何潜在的炎症效应。这一项目的成果将通过同行审查的出版物和会议介绍广泛传播。在使用纳米材料时，环境管理至关重要，该项目将通过提供数据来指导新材料的监管而造福社会。佛罗里达国际大学是一所西班牙裔服务机构，拥有非常多样化的学生群体，该项目将吸引来自科学和工程领域代表性不足的少数群体的学生。本科生和研究生将学习材料科学与工程、生物学和环境科学，以实现科学与工程教育的融合。本项目的总体目标是揭示二维过渡金属二硫属化物之间相互作用的基本模式，这些模式在环境相关的生物系统中具有潜在的应用。关注原始形式（非功能化）的材料将有助于评估材料加工和处理期间预期的主要接触类型。选择了适用于未来技术的代表性过渡金属二硫属化物材料：二硫化钼，电子应用的主要成分，和二硫化钛，一种潜在的光声治疗试剂。将通过研究材料与人皮肤成纤维细胞的相互作用以及吸入A549肺癌细胞来模拟皮肤暴露。此外，对于这些材料，所有已知的合成方法赋予可变的尺寸和表面性质，这是合成路线固有的，包括配体、缺陷和吸附物质。2-三维过渡金属二硫属化物也表现出在细胞环境中可能改变的多型性。研究人员假设过渡金属二硫属化物的性质与某些现象密切相关：i）。物理相互作用，涉及细胞摄取机制; ii）。体外相变，指细胞中的物质相变;和iii）.化学相互作用，可能发生在材料与细胞环境的界面处。 两种选定的材料二硫化钼和二硫化钛将通过所有已知的二维过渡金属二硫属化物合成方法合成，并以其原始形式分别与肺癌细胞和皮肤细胞相互作用。该项目有以下目标：确定二维过渡金属二硫属化物纳米片的合成方法与其原始形式的细胞摄取之间的相关性;通过原位拉曼光谱法阐明二维过渡金属二硫属化物多型体在细胞环境中的结构转变;并建立二维过渡金属二硫属化物性质与活细胞中潜在炎症效应之间的相关性。 该项目将有助于对所选细胞中的二维过渡金属二硫属化物进入机制、细胞环境对多型体的潜在影响以及暴露细胞的潜在炎症反应（作为纳米片表面化学的函数）的一般理解。佛罗里达国际大学是一所西班牙裔服务机构，拥有非常多样化的学生群体，该项目将吸引来自科学和工程领域代表性不足的少数群体的学生。本科生和研究生将从事材料科学与工程、生物学和环境科学的学习，以实现科学与工程教育的融合。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

Two-dimensional materials consist of atomically thin layers with defined crystal structure and large lateral dimensions. This project focuses on two-dimensional transition metal dichalcogenides. These materials emerged in the past decade due to their unique optoelectronic properties, which are suitable for a wide range of applications in modern computing, biosensing, and communications, and the Internet of Things. Although these 2-dimensional materials have promise in affordable technologies, very little is known concerning their behavior at the interface with environmentally-relevant biological systems. This project will investigate the behavior of two-dimensional nanomaterials interacting with mammalian cells, focusing on three distinct aspects: the mechanism of cellular uptake; the potential structural transformations of the nanomaterial in the mammalian cells; and the reactivity in the cellular environment, especially to understand any potential inflammatory effects. The results of this project will be widely disseminated through peer-reviewed publications and conference presentations. Environmental stewardship is critical when using nanomaterials and the project will benefit society by providing data to guide regulation of new materials. Florida International University is a Hispanic Serving Institution with a very diverse student population and this project will engage students from underrepresented minority groups in science and engineering. Undergraduate and graduate students will be engaged in learning materials science and engineering, biology and environmental science, toward a convergent science and engineering education.The overarching goal of this project is to uncover fundamental modes of interaction between two-dimensional transition metal dichalcogenides that have potential applications for environmentally-relevant biological systems. Focusing on materials in their pristine form (non-functionalized) will facilitate assessment of the primary type of exposure expected during processing and handling of materials. Representative transition metal dichalcogenide materials applicable for future technologies were selected: molybdenum disulfide, a major component of electronic applications, and titanium disulfide, a potential photoacoustic therapeutic reagent. Skin exposure will be simulated by studying the materials interaction with Human Skin Fibroblast cells, and inhalation with A549 lung cancer cells. In addition, for these materials all of the known synthetic methods confer variable size and surface properties, intrinsic to the synthetic route, including ligands, defects, and adsorbed species. 2-dimensional transition metal dichalcogenides also exhibit polytypism which might be altered in the cellular environment. The investigator hypothesizes that the properties of the transition metal dichalcogenides are strongly correlated with certain phenomena: i). Physical interactions, involving the mechanism of cellular uptake; ii). In vitro phase transformations, referring to material phase changes in the cell; and iii). Chemical interactions, that could occur at the interface of the material with the cellular environment. The two selected materials, molybdenum disulfide and titanium disulfide, will be synthesized through all known 2-dimensional transition metal dichalcogenide synthetic methods and used in their pristine form to interact with lung cancer cells and skin cells, respectively. The project has the following objectives: establish the correlation between the synthetic method of the 2-dimensional transition metal dichalcogenide nanosheets and their cellular uptake in pristine form; elucidate the structural transformations of 2-dimensional transition metal dichalcogenide polytypes within the cellular environment by in situ Raman spectroscopy; and establish the correlation between 2-dimensional transition metal dichalcogenide properties and potential inflammatory effects in living cells. This project will contribute to a general understanding of the 2-dimensional transition metal dichalcogenide entry mechanism in the selected cells, the potential impacts of cellular environment on polytypes, and the potential inflammatory responses of exposed cells, as a function of nanosheet surface chemistry. Florida International University is a Hispanic Serving Institution with a very diverse student population and this project will engage students from underrepresented minority groups in science and engineering. Undergraduate and graduate students will be engaged in learning materials science and engineering, biology and environmental science, toward a convergent science and engineering education.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.