Poster #085, University of California, Riverside
A Bioactive nHA-PLA Coating to Regulate Degradation and Enhance Bone Regeneration in Zinc-Alloy Spinal Implants
Mentors: Allison Sander (Grad Student), Anannya Khanna (Grad Student), Karla Rodriguez Pequeno (Grad Student); PI: Huinan Liu, PhD
Although titanium implants are currently the gold standard for spinal implants, they are permanent implants that can irritate nerves and require further surgeries to remove. Bioresorbable metal implants such as Zn alloys offer an alternative solution that will dissolve over time as the patient heals from the initial surgery. Our lab has previously studied various ratios of calcium-phosphate coatings on zinc alloys and found that the presence of hydroxyapatite, a naturally occurring, biocompatible mineral form of calcium phosphate, is vital for osteoblast adhesion and the overall integration of the implant with living bone tissue. In this project, nHA particles were synthesized using a co-precipitation and hydrothermal approach followed by calcination. These particles could be further integrated into a biodegradable polymer matrix such as polylactic acid (PLA) and coated onto a Zn alloy implant’s surface. The use of PLA will minimize a potential cytotoxic effect on native cells by controlling the release of metallic ions, while the nHA will encourage the osseointegration of the implant into the remaining bone structures by signaling native bone marrow stem cells (BMSCs) to rebuild the spinal bone. This form of treatment is especially critical because the spine is essential for daily activity and motion. Therefore, BMSCs must rapidly establish a strong bond between the implant and the bones to stabilize the implant for long-term success. Overall, implants with improved signaling and adhesion of BMSCs could lead to improvements for bone regeneration for millions of patients, reduce healthcare costs, and spare those patients the trauma of undergoing removal surgeries.