Medical Devices : Wound healing


Growth Factor Regulation in Blood Products for Improved Wound Healing

UW–Madison researchers have developed hydrogel microspheres for sequestering problematic growth factors, specifically VEGF, in patient-derived blood products. The degradable microspheres are functionalized with peptide ligands that selectively bind and remove unwanted VEGF from platelet rich plasma and other blood products before they are used in clinical procedures.

More Stable Collagen Mimetic Peptides for Wound Healing

UW–Madison researchers have developed a superior linkage between CMP strands that substantially improves their structural stability. The new linkage uses homocysteine in place of cysteine in one of the strands. The resulting bond reduces strain and can therefore be used to enhance CMP-based biomaterials and enable previously inaccessible molecular designs.

Click Chemistry-Based Multi-Enhanced Biomaterials Help Heal Wounds

The UW–Madison researchers have now adapted “click chemistry” in lieu of an external energy source to form the sIPNs. This allows a wider variety of sensitive bioactive molecules, including therapeutic cells, to be entrapped within the sIPNs, enhancing the clinical applicability of the technology.

Biodegradable, Biocompatible Tannin-Chitosan Composites for Therapeutic Applications

UW–Madison researchers have developed a new composite of tannin and chitosan.  The biodegradable and biocompatible composite can be formed into hydrogel films, 3-D foams, biogels, nanoparticles or liposome coatings for a variety of therapeutic applications.

This material combines the advantages of chitosan, which has blood-clotting and antimicrobial properties, with those of tannins, which have antibacterial, antifungal, antioxidant and wound healing properties.  As compared to chitosan alone, the composite has improved stability, higher drug loading capacity, better drug release properties, improved cell uptake, greater porosity, improved tensile strength and increased thermal stability.  In addition, this composite is non-cytotoxic in vitro.

Bioactive and Biocompatible Copolymers for Use in Medical Implants

UW-Madison researchers have combined polyurethane with naturally-occurring glycosaminoglycans, such as hyaluronic acid and dermatan sulfate, to create a new class of biomaterials with improved properties. The resulting copolymers combine the elasticity and mechanical strength of polyurethane with the biological properties of glycosaminoglycans. They have excellent hemocompatibility and biocompatibility for use in medical implant devices.

In addition, selecting the appropriate glycosaminoglycan allows the biological properties of the copolymer to be tailored to elicit specific physiological responses. For instance, the polyurethane-dermatan sulfate copolymer formulation is non-biofouling, while one version of the polyurethane-hyaluronic acid copolymer permits the growth of endothelial cells only.

Improved Wound Healing Using Patterned Gradients of Immobilized Biomolecules

UW-Madison researchers have developed a wound dressing with a patterned gradient of immobilized growth factors to accelerate wound healing. To create a platform that promotes directed migration of cells during dermal wound healing, growth factors are immobilized on a substrate in a pattern of increasing growth factor concentration, with the highest concentration typically at the center of the dressing. Cells migrate toward greater concentrations of growth factor, and their speed is determined by the slope of the gradient. The surface may also include an extracellular matrix protein, such as collagen, fibronectin or laminin, and/or a factor that promotes the formation of blood vessels.

Multi-Functional Matrix to Promote Wound Healing and for Other Biomedical Applications

Using Biofunctionalized Biomaterials to Recapitulate Tissue Structure Lost Due to Trauma or Underlying Disease to Improve Healing
UW–Madison researchers have developed semi-interpenetrating networks (sIPNs), a platform material that mimics the extracellular matrix and allows delivery of factors like therapeutic cells that promote healing to the wound bed. The sIPNs use a multi-functional hydrogel as a scaffold for damaged tissues. The polymer material consists of a biochemically-modified and cross-linked gelatin matrix, onto which are grafted various heterodifunctional polyethylene glycols (hPEGs). The hPEGs increase the biocompatibility and durability of the hydrogel and also provide attachment sites for therapeutic molecules. The biodegradable matrix allows for temporally and spatially controlled delivery of bioactive signals to modulate and complement the dynamics of the wound healing process, making these materials functional and clinically viable as wound dressings.