Apatite formation on ethylene-vinyl alcohol copolymer modified with silanol groups

✍ Scribed by Oyane, Ayako ;Minoda, Masahiko ;Miyamoto, Takeaki ;Takahashi, Ryoji ;Nakanishi, Kazuki ;Kim, Hyun-Min ;Kokubo, Tadashi ;Nakamura, Takashi

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 348 KB
• Volume: 47
• Category: Article
• ISSN: 0021-9304
• DOI: 10.1002/(sici)1097-4636(19991205)47:3<367::aid-jbm11>3.0.co;2-a

✦ Synopsis

The surfaces of ethylene-vinyl alcohol copolymer (EVOH) substrates were modified with silanol (Si-OH) groups, and their apatite forming ability was examined in a simulated body fluid (SBF) with ion concentrations nearly equal to those of human blood plasma or in a solution with ion concentrations 1.5 times those of SBF (1.5SBF). The surface modification of EVOH was carried out by reacting 3-isocyanatopropyltriethoxysilane, followed by hydrolysis of the ethoxysilyl groups into Si-OH groups. However, no apatite formation was observed on the EVOH substrate thus modified, even after 3 weeks in SBF and 1.5SBF. The Si-OH modified EVOH substrate was further modified by hydrolysis and polycondensation of tetraethyoxysilane (TEOS). It was found that the apatite forms on the TEOS-modified substrate within 3 weeks in 1.5SBF. These results suggest that the presence of a large amount of Si-OH groups (i.e., a cluster of Si-OH groups) on the substrate is prerequisite to apatite formation in the body environment. Apatite-EVOH composites prepared by this process might be useful as hard tissues substitutes.