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

这个I-Corps项目更广泛的影响/商业潜力是一个系统，以机械方式表征软材料。超软材料在细观尺度上的机械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，目前软质和超软材料的力学表征技术严重依赖于拉伸测试。主要局限性是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，以及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在超软材料的压痕拉上和拉下事件期间捕获机械性能。所提出的试验台的另一个新奇是通过光传感器的粘附事件的原位可视化。因此，该工具可以通过记录制造中成功的组织支架来改善制造仿生心脏补片的处理时间，控制质量，并提高植入的功能安全性。除此之外，该工具在食品生产、汽车润滑油生产和航空航天工业中也有潜在的应用。I-Corps的这个项目是基于开发一种能够在厘米级上精确表征软质和超软材料机械性能的系统。其包括附接到机械负载框架致动器的适配器、压头探针保持器、基于聚合物的压头探针、设置在压头探针下方并且被配置为保持软材料和超软材料的样品保持器、以及光传感器。该系统的独特优势包括：1）捕获粘附力和原位粘附事件的能力，2）涉及该测试方法的弹性模量范围为0.5 kPa至40 MPa，以及3）对传统桌面机械框架的适应性。除此之外，这种专有方法适用于各种仿生材料，如固体，半固体和液体形式，具有各向异性和异质性。对于组织工程，所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，它可以通过引导天然材料和人造材料之间的机械性能的相容性来有效地提高心脏补片的质量。该奖项反映了NSF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.