GOALI/Collaborative Research: Instabilities and Local Strains in Engineered Cartilage Scaffold

Johns Hopkins University, Baltimore MD

Investigators

Abstract

This Grant Opportunity for Academic Liaison with Industry (GOALI) collaborative research project will focus on the mechanical properties and deformation of cartilage scaffolds under external loads. Soft porous scaffolds are commonly used to promote cell growth for therapeutic applications in the repair and regeneration of different tissues, including cartilage and bone. The porosity of these scaffolds facilitates cell growth and the transport of nutrients. The mechanical function of such soft implants during the early stage of implantation is dominated by the scaffold that has to carry the applied load and maintain the integrity of cells within its pores. Structural instabilities, often encountered in soft porous materials, can both compromise the mechanical function of the scaffolds as well as damage the encapsulated cells. The research outcomes will advance national health and improve the quality of life for millions of people by transforming engineered cartilage scaffolds in order to maintain implant functionality, prevent cell death, and thus increase the probability of a successful implantation procedure. Furthermore, this collaborative project aims to engage several high-school and undergraduate students from underrepresented minorities through summer outreach programs at Cornell University and Johns Hopkins. This project integrates experimental, theoretical, and computational efforts in order to answer the following fundamental questions: (1) how do key microstructural characteristics of the porous scaffold affect the critical buckling load and the distribution of local strains; (2) how do the mechanical properties of the parent collagen influence the nonlinear response of the scaffolds; (3) how does a non-homogeneous distribution of a compliant filler material affect regions and modes of elastic stability. The research plan involves experiments on additively manufactured complex 3D architectures, state-of-the-art deformation mapping at the microscale, and the development of novel multiscale models of soft architected composites that capture all aspects of the material nonlinear mechanics. The research findings and predictive tools developed will have significant impact in several areas involving soft materials ranging from biological engineering and biomimetic systems to soft robotics. 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.