Oxidation of Titanium, RGD Peptide Attachment, and Matrix Mineralization of Rat Bone Marrow Stromal Cells
The aim of this study was to compare the efficacy of attachment of arginine-glycine-aspartic acid (RGD) peptide to titanium surfaces oxidized by different methods. Titanium surfaces were treated as follows: (1) treatment A: passivation in nitric acid, (2) treatment B: heated in air at 400°C for 1 hour, (3) treatment C: immersed in 8.8 M H2O2/0.1 M HCl at 80°C for 30 minutes, and (4) treatment D: treated as in treatment C and then heated at 400°C for 1 hour. RGD was attached to titanium samples treated as in treatments A through D. The quantity of attached RGD was determined by an enzyme-linked immunoabsorbent assay. Mineralization of a rat bone marrow stromal cell (RMSC) culture on the titanium surfaces after 21 days was determined y atomic absorption spectroscopy. The treatments were ranked according to quantity of RGD attached as C, A, B, and D. Twenty-one days after RMSC culture, the degree of mineralization was significantly higher for treatment C than for treatments A, B, and D and for controls. The efficacy of RGD attachment varies with the oxidation treatment given to titanium. Oxidation in H2O2/0.1 M HCl at 80°C provided the best overall surface for RGD attachment as well as calcified matrix formation of RMSCs.Abstract

Contributor Notes
Francis K. Mante, PhD, DMD, is an associate professor of Restorative Dentistry and director for Biomaterials; Kevin Little, BS, is a research assistant; Mamle O. Mante, MS, DMD, is a clinical associate professor of Restorative Dentistry; and Christopher Rawle, BS, is a graduate student with the University of Pennsylvania School of Dental Medicine, 4001 Spruce Street, Philadelphia, PA 19104.
George R. Baran, PhD, is a professor and director, Center for Bioengineering and Biomaterials, at Temple University, Philadelphia, Pa.
Address correspondence to Dr Mante (mantefk@pobox.upenn.edu).