Colloquium: Mark Tibbitt

Title:

Macromolecular Engineering of Advanced Biomaterials

Abstract:

The core of my research integrates concepts from organic synthesis, polymer physics, and materials engineering to design and assemble advanced polymeric materials. Organic synthesis provides a handle over molecular scale properties; polymer physics enables an understanding of how molecular assembly controls macroscale function; materials engineering facilitates processing, scalable production, and implementation of our rationally-designed materials in a variety of applications. Specifically, we tailor structural and chemical details at the molecular scale to enable predictive and tunable control over emergent material properties. Our user-programmable and responsive materials are employed to understand fundamental processes in biology and materials science, and translated to solve clinical problems in the fields of drug delivery, regenerative medicine, and biomedical diagnostics. This approach to the design and application of soft materials will be demonstrated in two examples.

In the first part of the talk, we will explore how rationally-designed photoresponsive hydrogels can be used to control and understand cell-matrix interactions. Cell function and fate decisions are regulated by complex interactions with the surrounding extracellular matrix (ECM), which are heterogeneous and dynamic in three-dimensional space and time. To decode the cell-matrix conversation, responsive biomaterials that mimic the native ECM and afford user-defined and spatiotemporal control over biophysical and biochemical properties are needed. To address this, we have developed photoresponsive hydrogels whose properties can be modulated in a precise and predictable manner in real-time with light. In particular, this material platform enabled us to reveal unique aspects of stem cell plasticity and mechanical memory. In the second part of this talk, we will explore a unique class of shear-thinning and self-healing hydrogels that are fabricated from selective and reversible polymer-nanoparticle (PNP) interactions. An understanding of the underlying physics of PNP hydrogels was developed and leveraged to design an injectable drug delivery depot for local delivery of both hydrophilic and hydrophobic drugs.Biomaterials that allow for minimally-invasive application of a therapeutic-releasing depot locally at the target site of action are needed to limit off-target side effects and achieve therapeutic potency. Here, we will illustrate how the PNP hydrogel platform can be leveraged for local drug delivery in the management of chronic disease.

4:00 PM - Refreshments, Building 380 Room 380C

4:15 PM - Talk, Buildling 380, Room 380C