Enhancement of Osteoblast Gene Expression by Mechanically Compatible Porous Si-rich Nanocomposite.
From: Center for Biomedical Engineering, Graduate School, University of Kentucky, Lexington, Kentucky 40506, USA.
Journal of biomedical materials research. Part B, Applied biomaterials
- Publish Date: May 2007
- ISSN: 1552-4973
- Volume: 81
- Issue: 2
- Pages: 387-96
- Medium: Print
- Language: English
- Citation (JAMA): Gupta Gautam, El-Ghannam Ahmed, Kirakodu Sreenatha, et al. Enhancement of Osteoblast Gene Expression by Mechanically Compatible Porous Si-rich Nanocomposite.. J. Biomed. Mater. Res. Part B Appl. Biomater. May 2007;81:387-96
Abstract
Synthesis of a porous bioactive ceramic implant for load bearing applications is a challenging task in maxillofacial and orthopedic surgeries. A novel bioactive resorbable silica-calcium phosphate nanocomposite (SCPC) has recently been introduced as a potential bone graft. In the present study, we employed SCPC to develop a resorbable porous scaffold and analyzed the effects of composition and porosity on the mechanical properties. The ranges of compressive strength and modulus of elasticity of SCPC containing 32-56% porosity were 1.5-50 MPa and 0.14-2.1 GPa, respectively, which matched the corresponding values for trabecular bone. The compressive strength of dense SCPC was dependent on the Si content and acquired values (93-285 MPa) comparable to that of cortical bone. The superior mechanical properties of SCPC are attributed to the intricate interactions at the boundaries of the nanograins and to the homogenous distribution of hierarchical pore-structure throughout the material volume. X-ray computed tomography and mercury porosimetry analyses revealed high interconnectivity of the pores in the size range 3 nm to 650 microm. Quantitative real-time PCR analyses showed that neonatal rat calvarial osteoblasts attached to Si-rich SCPC expressed 5- and 26-fold higher osteocalcin mRNA levels compared to cells attached to ProOsteon hydroxyapatite disks and tissue culture polystyrene plates respectively, after four days in culture. Results of the present study strongly suggest that porous, bioactive resorbable SCPCs can serve as tissue engineering scaffolds for cell delivery to treat load-bearing bone defects in orthopedic and maxillofacial surgeries.
Mesh Headings (Keywords): Animals, Biocompatible Materials, Biomechanics, Calcium Phosphates, Compressive Strength, Elasticity, Gene Expression, Humans, Materials Testing, Microscopy, Electron, Scanning, Nanocomposites, Osteoblasts, Osteocalcin, RNA, Messenger, Rats, Silicates, Tissue Engineering
Check for Full Text / PubMed Unique Identifier (PMID): 17034000
This abstract is part of PubMed, a service of the U.S. National Library of Medicine. PubMed includes more than 17 million citations from MEDLINE and other life science journals for biomedical articles. See Copyright and Disclaimers.
Linked medical terms appearing on this page are added by Healia to help readers find more information and are not part of the original PubMed document.
The data herein was last updated on July 8th, 2008 and may not reflect the most current and accurate data available from NLM.