Surface engineering of stainless steel materials by covalent collagen immobilization to improve implant biocompatibility.
It was shown recently that the deposition of thin films of tantalum and tantalum oxide enhanced the long-term biocompatibility of stainless steel biomaterials due to an increase in their corrosion resistance. In this study, we used this tantalum oxide coating as a basis for covalent immobilization of a collagen layer, which should result in a further improvement of implant tissue integration. Because of the high degradation rate of natural collagen in vivo, covalent immobilization as well as carbodiimide induced cross-linking of the protein was performed. It was found that the combination of the silane-coupling agent aminopropyl triethoxysilane and the linker molecule N,N'-disulphosuccinimidyl suberate was a very effective system for collagen immobilizing. Mechanical and enzymatic stability testing revealed a higher stability of covalent bound collagen layers compared to physically adsorbed collagen layers. The biological response induced by the surface modifications was evaluated by in vitro cell culture with human mesenchymal stem cells as well as by in vivo subcutaneous implantation into nude mice. The presence of collagen clearly improved the cytocompatibility of the stainless steel implants which, nevertheless, significantly depended on the cross-linking degree of the collagen layer.
Müller
Rainer
R
Institute of Physical and Theoretical Chemistry, University of Regensburg, Germany. rainer.mueller@chemie.uni-regensburg.de
Abke
Jochen
J
Schnell
Edith
E
Macionczyk
Frank
F
Gbureck
Uwe
U
Mehrl
Robert
R
Ruszczak
Zbigniev
Z
Kujat
Richard
R
Englert
Carsten
C
Nerlich
Michael
M
Angele
Peter
P
D000327:Adsorption; D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D020099:Coated Materials, Biocompatible / Q000737:chemistry / Q000494:pharmacology; D024042:Collagen Type I / Q000008:administration & dosage* / Q000737:chemistry*; D006801:Humans; D020007:Implants, Experimental; D008422:Materials Testing; D051379:Mice; D008819:Mice, Nude; D011485:Protein Binding; D013193:Stainless Steel / Q000737:chemistry*; D013234:Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D013499:Surface Properties
D020099:Coated Materials, Biocompatible; D024042:Collagen Type I; D013193:Stainless Steel