|Nanoscale Bioceramics in Bone Implants and Protein Delivery |
|Susmita Bose, Washington State University|
12:00 Noon, CCR 201
Synthetic calcium phosphates (CaPs) have been used in orthopedics and dentistry because of their excellent biocompatibility. Most commonly used synthetic CaPs are bioactive hydroxyapatite (HAp, CalQ(P04)6(OH)z) and bioresorbable tricalcium phosphate (TCP, Ca3(P04)z). One of the key scientific issues to mimic the properties of natural bone is their nanoscale microstructures. Nanostructured CaPs can not only improve mechanical properties due to their better sinterability, but also can carry more drugs/proteins to make them more biologically available due to the presence of nanosized receptors in the cell membrane. We have synthesized CaP based nanoscale ceramics using different template systems with controlled size and morphology. Nanoparticles were characterized using BET surface area analyzer, powder X-ray diffraction (XRD),dynamic light scattering (DLS) techniques, and transmission electron microscopy (TEM). Doped TCP showed that their resorbability, mechanical and biological properties could be controlled based on the dopants. Microwave sintering of nanoscale CaP compacts showed improvement in mechanical as well as biological properties. In vitro analysis showed excellent human osteoblast (HOB) cell adhesion, growth and differentiation. hnmunocytochemistry showed strong alkaline phosphatase (ALP) expression, which is a major characteristic marker for osteoblast differentiation. Our study on both nanoscale CaPs and calcium silicates (CS) showed that protein loading and release could be controlled based on synthesis and processing parameters. This presentation will discuss synthesis and processing of both calcium phosphate and calcium silicate nanoparticles and their use to study human osteoblast cell response and protein release behavior.