Costantini A, Luciani G, Silvestri B, Tescione F, Branda F
Dipartimento di Ingegneria dei Materiali e della Produzione, Università di Napoli Federico II, Piazzale Tecchio, 80-80125 Napoli, Italy.
J Biomed Mater Res B Appl Biomater. 2008 Jul;86(1):98-104. doi: 10.1002/jbm.b.30993.
A hybrid of poly(2-hydroxyethylmethacrylate) (pHEMA), a polymer widely employed for biomedical applications, and silica gel, exhibiting a well-known bioactivity, was produced by sol-gel. The amount of the inorganic precursor, tetraethoxysilane (TEOS), was mixed to the organic monomer, so as to have a final concentration of 30% (w/w) of silica gel to the mass of polymer. The nanocomposite was characterized for its composition by thermogravimetric (TG) analysis, swelling behavior, glass transition temperature using differential thermal analysis (DTA), morphology through scanning electron microscopy (SEM), and bioactivity using FT-IR spectroscopy, SEM, and energy dispersive system (EDS). The nanocomposite showed phase separation between the polymer and the silica gel, improved thermal stability and swelling properties and higher glass transition temperature than pHEMA. Moreover, bioactive SiO(2) gel nanoparticles promoted apatite formation on the surface of the modified hydrogel, when it was soaked in SBF. Therefore, the obtained bioactive nanocomposite can be used to make bioactive scaffold for bone engineering.
通过溶胶 - 凝胶法制备了一种聚甲基丙烯酸2 - 羟乙酯(pHEMA,一种广泛应用于生物医学领域的聚合物)与具有众所周知生物活性的硅胶的复合材料。将无机前驱体四乙氧基硅烷(TEOS)的量与有机单体混合,以使硅胶相对于聚合物质量的最终浓度为30%(w/w)。通过热重分析(TG)、溶胀行为、使用差热分析(DTA)的玻璃化转变温度、扫描电子显微镜(SEM)的形态以及傅里叶变换红外光谱(FT - IR)、SEM和能量色散系统(EDS)的生物活性对该纳米复合材料的组成进行了表征。该纳米复合材料在聚合物和硅胶之间表现出相分离,具有改善的热稳定性和溶胀性能,并且玻璃化转变温度高于pHEMA。此外,当将改性水凝胶浸泡在模拟体液(SBF)中时,具有生物活性的SiO₂凝胶纳米颗粒促进了磷灰石在其表面的形成。因此,所获得的生物活性纳米复合材料可用于制造骨工程用生物活性支架。