TN HYDROGELS AS A POTENTIAL ANTI-INFLAMMATORY DRUG DELIVERY SYSTEM TARGETED TO OSTEOARTHRITIC KNEES

Arthritis affects 26.3% of adults and approximately 50,000 children in the United States [1]. Hydrogel drug-delivery systems have been considered as a viable option for drug delivery to arthritic articular cartilage in the knee. To determine physiologically relevant loading, a Qualisys motion capture system was used to analyze the gait of college-aged females as they took several steps on a flat surface, then stepped onto a force plate. The motion capture and force plate data was used to determine maximum force exerted on the knee during normal gait. Three different alginate-based hydrogels, where the superior one had a triple interpenetrating graphene oxide network (TN hydrogels), were investigated for use as an antiinflammatory drug delivery system in a human knee joint. Physiologically relevant cyclic loading was performed to ensure that the TN hydrogel could withstand the force exerted in the knee. The TN hydrogel experienced a change in energy of 50% after cyclic loading (10.6 ± 15.0 Pa) and survived high stresses of 4 kPa, which is 80 magnitudes larger than observable gait forces as measured in this study. From a mechanical perspective, TN hydrogel appears to be mechanically viable for arthritis drug delivery. In addition, based on calculations and Flory-Rehner equations, the pore size of the TN hydrogel is adequate for encapsulating most NSAIDs, which have a molecule size ≤ 5μm.