3D Bioprinting of Complex Tissue Structures Using Nanoengineered Ionic-Covalent Entanglement (NICE) Bioinks

工程复杂组织可以模拟、增强或替代天然组织的功能，在治疗由损伤、衰老和疾病引起的器官衰竭方面具有巨大的潜力。3D生物打印是一种新兴的方法，用于快速制造复杂的组织结构，使用细胞负载的水凝胶，称为生物墨水。然而，由于缺乏合适的可打印并能指导细胞功能的生物墨水，3D生物打印在进展中遇到了瓶颈。该项目的重点是设计一种用于3d打印的纳米工程离子共价纠缠（NICE）生物墨水。NICE生物墨水结合了两种方法——使用二维纳米硅酸盐的纳米复合材料和由甲基丙烯酸明胶（一种基于胶原蛋白的生物墨水，常用于生物打印）和k-卡拉胶（一种基于多糖的凝胶，常用于增稠和稳定）形成的ICE网络——以获得优于单独使用任何一种方法的机械性能。这项工作将导致一种新的平台技术来选择性地控制和模式细胞行为，这将对人类健康产生广泛的科学影响；特别是再生工程和治疗输送。新型生物墨水家族的开发也将刺激生物制造的增长，从而对社会和国民经济产生积极影响。综合多学科研究平台将提供一个独特的环境，以吸引，激励和留住学生，特别是在科学和工程教育中代表性不足的群体。该项目将通过一系列不同的K-12活动提供教育和推广机会，包括：制作教育视频；培训教师;让当地学校参与课后活动；并接待高中生进行研究。具体而言，将开发一系列教育和研究视频，以吸引和促进对纳米材料和生物打印的认识。将通过流行的社交媒体网站（包括博客、Facebook、Flickr、Pinterest、SlideShare、Twitter、Vimeo和YouTube）分享和分发视频，并通过与在线K-12视频门户网站（如可汗学院）互动，扩大推广范围。该项目解决了生物医学工程中的一个关键挑战——如何设计由生物分子、细胞和支架组成的三维复杂结构——通过设计一种新型的纳米工程离子共价纠缠（NICE）生物墨水家族，用于3d打印来控制和图案细胞行为。所采取的方法将阐明离子共价纠缠（ICE）网络加载独特的二维（2D）纳米硅酸盐的关键基本性质。这项研究将揭示纳米材料、生长因子和人类细胞之间的相互作用，为利用和增强这些相互作用的新型纳米工程方法铺平道路。知识贡献包括：1)引入一种新的材料设计（NICE）来形成剪切变薄的生物墨水，使用2D纳米材料和离子共价纠缠（ICE），将使细胞沉积在复杂的3D结构中，从而促进对复杂微环境中细胞-生物材料相互作用的理解和认识；2)阐明二维纳米硅酸盐与ICE网络之间的相互作用将促进对利用非共价相互作用机械强化水凝胶网络的基本理解；3)通过消除不稳定疗法的复杂化学修饰，将2D纳米硅酸盐建立为即插即用型治疗药物输送的模块化方法。了解二维纳米材料与生物分子之间的相互作用将为长期保持不稳定疗法的生物活性提供见解，并将导致新现象的发现；4)建立一种持续有效地递送治疗药物以调节细胞功能的新模式，最终将导致更有效递送系统的发展。

PI: Gaharwar, Akhilesh K.Proposal: 1705852Engineering complex tissues that can mimic, augment, or replace native tissue functions holds enormous potential for treating organ failures resulting from injuries, aging, and diseases. 3D bioprinting is an emerging approach for rapid fabrication of complex tissue structures using cell-loaded hydrogels, called bioinks. However, 3D bioprinting has hit a bottleneck in progress due to the lack of suitable bioinks that are printable and can guide cell functions. This project focuses on designing a novel family of nanoengineered ionic-covalent entanglement (NICE) bioinks for 3D-printing. The NICE bioink combines two approaches - nanocomposites using 2D nanosilicates and ICE networks formed from gelatin methacrylate (a collagen based bioink often used in bioprinting) and k-carrageenan (a polysaccharide based gel often used for thickening and stabiliazation) - to achieve mechanical properties superior to either approach alone. This work will lead to a novel platform technology to selectively control and pattern cell behavior that will have broad scientific impact on human health; specifically, regenerative engineering and therapeutic delivery. The development of a new family of bioinks will also spur growth in biofabrication, leading to positive impacts on society and the national economy. The integrated multidisciplinary research platform will provide a unique environment to attract, motivate, and retain students, particularly underrepresented groups, in science and engineering education. The project will provide educational and outreach opportunities through a diverse array of K-12 activities, including: development of educational screencasts; training teachers; engaging local schools in after-school programs; and hosting high school students for research. Specifically, a range of educational and research screencasts will be developed to engage and promote awareness about nanomaterials, and bioprinting. Outreach will be extended by sharing and distributing the screencasts via popular social media sites (including blogs, Facebook, Flickr, Pinterest, SlideShare, Twitter, Vimeo, and YouTube) and by interacting with online K-12 video portals such as Khan Academy.This project addresses a key challenge in biomedical engineering - how to engineering three-dimensional complex structures consisting of biomolecules, cells, and scaffolds - by designing a novel family of nanoengineered ionic-covalent entanglement (NICE) bioinks for 3D-printing to control and pattern cell behavior. The approach taken will elucidate key fundamental properties of ionic covalent entanglement (ICE) networks loaded with unique, two-dimensional (2D) nanosilicates. The research will reveal the interactions among nanomaterials, growth factors, and human cells, paving the way for novel nanoengineered approaches to harness and augment these interactions. Intellectual contributions include: 1) introducing a novel material design (NICE) to form shear-thinning bioinks, using 2D nanomaterials and ionic-covalent entanglement (ICE), will enable deposition of cells in complex 3D structures which in turn will advance understanding and knowledge of cell-biomaterial interactions in complex microenvironments; 2) Elucidating interactions between 2D nanosilicates and the ICE network will advance fundamental understanding for leveraging non-covalent interactions to mechanically reinforce hydrogel networks; 3) establishing 2D nanosilicates as a modular approach for plug-and-play types of therapeutics delivery will be facilitated by eliminating complex chemical modification of labile therapeutics. Understanding the interactions between 2D nanomaterials and biomolecules will provide insight into retaining bioactivity of labile therapeutics for prolonged durations and will lead to discovery of new phenomena; and 4) establishing a new paradigm for sustained and effective delivery of therapeutics to modulate the cellular function will ultimately lead to development of more effective delivery systems.