Nanomanufacturing of Biopolymer Nanofiber Hierarchical Assemblies

生物聚合物纳米纤维分层组件的纳米制造

• 批准号: 1462916
• 负责人: Amrinder Nain
• 金额: $ 30万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-05-01 至 2019-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1462916&HistoricalAwards=false
• 关键词: Nanomanufacturing; Biopolymer; Nanofiber; Hierarchical; Assemblies

Immediate cellular environment, commonly referred to as the extracellular matrix, consists of micro/nanofibers (diameter: microns to sub-100 nanometers) and serves as a scaffold upon which most cells in the body attach and receive mechanical and chemical cues. An increased awareness of the role of alignment in extracellular matrix-cell interactions and the role of biophysical cues in development and disease models including cancer has necessitated the development of fiber manufacturing technologies mimicking the native environments for in vivo translational and in vitro cell behavior studies. Electrospinning is the most commonly used manufacturing method to fabricate nanofibers. However, it still lacks precise control on fiber diameter, spacing and orientation. This award utilizes a non-electrospinning fiber manufacturing platform to architect precise biophysical environments for cell studies through improved spinnability of biopolymers with control on fiber diameter, spacing and orientation in multiple layers. The resulting constructs can be instrumental in developing implantable scaffolds for tissue engineering, and single cell diagnostic platforms. Therefore, results from this research will benefit the U.S. economy and society. This multidisciplinary research involves elements from disciplines such as manufacturing, polymer physics, biology, mechanics and mechanical engineering. The award will help broaden participation of underrepresented groups in engineering research and positively impact engineering education at both undergraduate and graduate levels.The physics of polymer fiber formation at the nanoscale involves a delicate balance between solution rheology and applied external forces, which makes nanomanufacturing and hierarchical assembly of nanofibers extremely challenging. To augment our capabilities in fiber manufacturing, a non-electrospinning nanofiber manufacturing platform will be used to study fiber spinnability in this work. Due to elimination of electric source in the manufacturing process, the platform will provide superior control on fiber diameter, orientation, spacing and assembly, particularly in multiple layers. Using poly (lactic-co-glycolide acid) and fibrinogen as model polymer systems, this project will develop fiber spinnability scaling laws representing fiber diameter design space spanning a wide range of solution rheologies and processing parameters. Furthermore, mechanical tensile testing of single fibers using atomic force microscopy at different strain rates will provide the fiber probability failure Weibull distributions in the manufacturing process. This research will fill the knowledge gap on the spinnability of biopolymers and for the first time provide the ability to manufacture custom architectures representing gradients in biophysical cues. The overall research will thus provide a roadmap to design and build scaffolds of biopolymers with improved quality, scalability and repeatability.

直接细胞环境，通常称为细胞外基质，由微/纳米纤维（直径：微米至亚100纳米）组成，充当支架，体内大多数细胞附着在其上并接收机械和化学信号。人们越来越认识到排列在细胞外基质-细胞相互作用中的作用以及生物物理线索在发育和疾病模型（包括癌症）中的作用，因此有必要开发模仿天然环境的纤维制造技术，用于体内转化和体外细胞行为研究。静电纺丝是制造纳米纤维最常用的制造方法。然而，它仍然缺乏对纤维直径、间距和方向的精确控制。该奖项利用非静电纺丝纤维制造平台，通过控制多层纤维直径、间距和方向，提高生物聚合物的可纺性，为细胞研究构建精确的生物物理环境。由此产生的结构有助于开发用于组织工程的可植入支架和单细胞诊断平台。因此，这项研究的结果将有利于美国经济和社会。这项多学科研究涉及制造、聚合物物理、生物学、力学和机械工程等学科的要素。该奖项将有助于扩大代表性不足的群体对工程研究的参与，并对本科生和研究生的工程教育产生积极影响。纳米级聚合物纤维形成的物理学涉及溶液流变学和施加的外力之间的微妙平衡，这使得纳米纤维的纳米制造和分层组装极具挑战性。为了增强我们在纤维制造方面的能力，本工作将使用非静电纺丝纳米纤维制造平台来研究纤维的可纺性。由于制造过程中消除了电源，该平台将对纤维直径、方向、间距和组装（尤其是多层）提供卓越的控制。该项目将使用聚（乳酸-乙交酯酸）和纤维蛋白原作为模型聚合物系统，开发代表纤维直径设计空间的纤维可纺性缩放定律，涵盖广泛的溶液流变学和加工参数。此外，使用原子力显微镜在不同应变率下对单纤维进行机械拉伸测试将提供制造过程中纤维失效概率威布尔分布。这项研究将填补生物聚合物可纺性方面的知识空白，并首次提供制造代表生物物理线索梯度的定制架构的能力。因此，整体研究将为设计和构建具有更高质量、可扩展性和可重复性的生物聚合物支架提供路线图。