I-Corps: Meso-indentation System for Ultra-soft Biomaterials

这个I-Corps项目的更广泛的影响/商业潜力是一个机械表征软材料的系统。超软材料在中观尺度上的力学表征对于组织工程支架、结构和包装材料、泡沫和粘合剂、洗涤剂和化妆品、油漆、食品添加剂、润滑剂和燃料添加剂至关重要。然而，目前软质和超软质材料的力学表征技术在很大程度上依赖于拉伸测试。主要的限制是1)由于难以制备均匀样品而导致的高标准偏差，2)测试后样品损坏，3)无法测量粘性液体材料。这种细观压痕方法的独特优势是能够捕捉超软材料在压痕拉入和拉脱过程中的机械性能。该试验台的另一个新颖之处是通过光传感器对粘附事件进行现场可视化。因此，该工具可以通过记录制造过程中成功的组织支架，缩短制造仿生心脏贴片的加工时间，控制质量，提高植入的功能安全性。除此之外，该工具在食品生产、汽车用油生产和航空航天工业中也有潜在的应用。I-Corps项目的基础是开发一种能够在厘米尺度上对软质和超软质材料进行精确机械性能表征的系统。它包括连接到机械负载框架致动器的适配器、压头探头支架、基于聚合物的压头探头、位于压头探头下方并配置为容纳软质和超软质材料的样品支架，以及光传感器。该系统的独特优势包括1)能够捕获粘附力和原位粘附事件，2)涉及该测试方法的弹性模量范围从0.5 kPa到40 MPa，以及3)对传统桌面机械框架的适应性。除此之外，该专利方法适用于各种具有各向异性和非均相特性的仿生材料，如固体、半固体和液体形式。对于组织工程，获得的数据将提供关键的基准值，并评估生物材料或生物结构用于组织治疗的可行性。例如，通过引导天然材料与人工材料之间力学性能的相容性，可以有效提高心脏补片的质量。它还限制并发症，提高功能表现，促进成熟，减少心脏病患者住院。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The broader impact/commercial potential of this I-Corps project is a system to characterize soft materials mechanically. Mechanical characterization of ultra-soft materials on the meso-scale is critical for tissue engineering scaffolds, structural and packaging materials, foams and adhesives, detergents and cosmetics, paints, food additives, lubricants, and fuel additives. However, the current mechanical characterization technique for soft and ultra-soft materials relies heavily on tensile testing. The main limitations are 1) high standard deviation due to difficulty preparing uniform samples, 2) sample damage after testing, and 3) inability to measure viscous liquid materials. The unique advantage of this meso-indentation methodology is the ability to capture mechanical properties during indentation pull-on and pull-off events of ultra-soft materials. Another novelty of the presented testbed is the in-situ visualization of adhesion events through a light sensor. Therefore, this tool can improve processing time in manufacturing biomimetic cardiac patches, control the quality, and improve the functional safety for implantation by documenting successful tissue scaffolds in manufacturing. Beyond that, this tool also has potential applications in food production, automotive oil production, and aerospace industries.This I-Corps project is based on developing a system capable of accurate mechanical performance characterizations for soft and ultra-soft materials on the centimeter scale. It comprises an adaptor attached to the mechanical load frame actuator, an indenter probe holder, a polymer-based indenter probe, a sample holder disposed below the indenter probe and configured to hold the soft and ultra-soft material, and a light sensor. The unique advantages of this system include 1) the ability to capture adhesion forces and in-situ adhesion events, 2) the elastic modulus range that concerns this testing methodology ranges from 0.5 kPa to 40 MPa, and 3) adaptability to conventional tabletop mechanical frames. Beyond that, this proprietary method works for a wide range of biomimetic materials, such as solids, semi-solid, and liquid forms, with anisotropic and heterogeneous properties. For tissue engineering, the acquired data will provide critical benchmarking values and evaluate the feasibility of biomaterials or bio-constructs for tissue therapies. For example, it can effectively improve the quality of cardiac patches by guiding the compatibility of mechanical properties between native and artificial materials. It also limits complications, enhancing functional performances, improving maturation, and reducing cardiac patients' hospitalization.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.