Research Project: Hydrogels
Hydrogels are a highly variant class of materials abundant in medical devices. They are crosslinked polymer networks that swell but do not dissolve in water. Hydrogels can be made of synthetic polymers like PEG (polyethylene glycol), or natural polymers like hyaluronic acid. Their performance in medical devices depends critically on their specific chemistry, which includes but is not limited to the choice of polymer, molecular weight, degree of crosslinking, osmolality, concentration and manufacturing reaction scheme. Hydrogel-based medical devices (e.g., abdominal adhesion barriers, contact and intraocular lenses, drug-eluting stents, tissue scaffolds, tissue sealants, cosmetic dermal fillers, encapsulation media) pose unique regulatory questions, with the paramount issues changing as each device goes through deployment, mechanism of action, and clearance. For example, surgical tissue sealants require a specific in situ crosslinking time, while adhesion barriers require a specific degradation/clearance window.
Task 1: Wetting and Dewetting of Viscoelastic Hydrogels
The goal of this task is to improve the understanding of how viscoelastic hydrogels stick to, detach from, and slide between surfaces. The adhesive and lubricating properties of hydrogels are critical to the performance of tissue sealants and adhesion barriers used in ob-gyn, cardiovascular, neuro and cosmetic dermatological applications, as well as in mucosal drug delivery media. A limiting aspect to the performance of these device groups is the ability of a hydrogel to wet a surface and/or disrupt an interface, and then persist for the duration of its use.
Task 2: Degradation of Hyaluronic Acid
The goal of this task is to understand the effect of hydrogel chemistry on hydrogel performance properties, such as hydrogel stability, transport properties, and interaction with living cells/tissue, as they relate to the implantable medical devices and combination (device/biologic) products.