I-Corps: Biodegradable Piezoelectric Cartilage Graft with Physical Exercise for Osteoarthritis Treatment

The broader impact/commercial potential of this I-Corps project is the development of a biodegradable piezoelectric tissue scaffold for promoting cartilage healing. More than 32.5 million American adults suffer from osteoarthritis (OA), which is the most common chronic joint condition. Yet current medicines, including analgesics and anti-inflammatory drugs, only alleviate symptoms but do not cure the disease. The golden treatment so far has been to use replacement cartilage autografts or allografts. These grafts, however, struggle with problems of donor site morbidity, immune rejection, infection, and limited tissue supply. Therefore, there is a strong customer need for technology that can promote the healing of cartilage and enhance OA treatment efficacy. Additionally, the current OA treatments are expensive, with an estimated annual cost of $16 000 per patient. As such, the increasing prevalence of osteoarthritis presents a substantial market opportunity for new treatments. This I-Corps project is based on the development of a biodegradable piezoelectric tissue scaffold made from electrospun poly-L-lactic acid (PLLA) for use in cartilage repair. Currently, conventional piezoelectric materials such as lead zirconate titanate (PZT), polyvinylidene fluoride (PVDF), and barium titanate are either toxic and/or non-degradable. These properties render them unfavorable for certain applications, such as for regenerative medicine, due to the safety concern and the requirement for invasive removal surgery. Unlike these materials, PLLA is an attractive alternative piezoelectric biomaterial as it is safe and biodegradable. However, it is challenging to process PLLA into an easy-to-use form with highly effective and stable piezoelectricity for practical applications. The proposed technology is based on a materials process to create biodegradable, flexible PLLA nanomembranes that possess a controllable and outstanding piezoelectric response. This piezoelectric nanomembrane may be a safe platform for a bioresorbable, battery-less tissue graft that is able to generate electrical charge to promote the healing of cartilage and enhance the efficacy of osteoarthritis treatment. Results show that the piezoelectric PLLA scaffold tested in critical-sized osteochondral defects in an animal model under applied joint-load during rehabilitation activities or doing exercise may act as a battery-free electrical stimulator to promote cartilage healing. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.