Research

Biomaterials Development

Injectable In Situ Polymerizing Bone Grafts “Bone Foam”

Base catalyzed thiol-acrylate Michael addition provides a platform for the development of synthetic composites for use as in situ polymerizing grafts and augments for bone tissue engineering.

Micro-CT data of the L4 (top) and L5 (bottom) vertebral bodies

Micro-CT data of the L4 (top) and L5 (bottom) vertebral bodies

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Hybrid Semisynthetic ECM Gels

Human adipose is a readily available source of bioactive material for use in the development of grafts and augments.  The adipose, which is harvested via lipectomy from consenting donors, would normally be discarded as waste during the course of surgery.  After removing resident cells and processing the tissue a potentially usable proteinaceous extracellular matrix (ECM) is obtained containing components such as laminin, fibronectin, and collagen I-IV.  A  hybrid (semi-synthetic) microenvironment is created combing signaling factors and structures found in naïve adipose tissue and synthetic biomaterials to promote progenitor cell attachment, proliferation and repair of functional tissue.

Quasi 3-D Tissue Culture-Cell Sheets

Stackable cell sheets allow for the development of scaffold-free quasi 3-D cell culturing techniques. These structures can more closely represent the in vivo tissue environment allowing us to probe the complex cellular interactions during tissue formation and repair. Stacked stem cell sheets may also provide unique clinical tools for tissue repair and regeneration.

Immunofluorescence image of cell sheet using F-Actin staining

Immunofluorescence image of cell sheet using F-Actin staining

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Focal adhesion points of the hASCs seeded on Thiol-Acrylate polymer

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F actin and nucleus staining of the seeded hASCs on TMPeTA polymer

Spatiotemporal Control of Post Translational Gene Regulation

Optically Modulated Gene Regulation

The development of clinically relevant antisense therapeutics for tissue engineering requires improved control over the spatiotemporal delivery of siRNA therapeutics. Photomodulated delivery of siRNA using plasmonic nanoparticles has proven to be an effective tool to control the differentiation and function of progenitor cells both in vitro and in vivo.   In this project we aim to develop new optically responsive tools and techniques to spatiotemporally modulate the multiplexed activation of siRNA.

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Gold nanoparticles functionalized with photo-cleavable nitrobenzyl-linked miR148b, suspended in DI water

Targeted Magnetically Modulated Gene Regulation

Magnetically responsive materials provide a convenient means to modulate the spatial and temporal activation of caged therapeutics in deep tissue. This effort aims to develop spatial targeted, magnetically responsive elements for multiplexed gene regulation at depth to provide spatiotemporal control of antisense regulators of tissue repair and regeneration.

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Sample setup for MNPs activated under alternating magnetic field using RF induction heater (PLA-made petri-dish holder and insulated copper coil shown)