Department of Life Sciences, University of Trieste, Via Licio Giorgieri 1, 34127 - Trieste, Italy.
Biomacromolecules. 2010 Mar 8;11(3):583-92. doi: 10.1021/bm9011419.
Bisphenol A glycidylmethacrylate (BisGMA)/triethyleneglycol dimethacrylate (TEGDMA) thermosets and composites are well-known examples of biomaterials for dental applications that are receiving growing interest for orthopedic applications. While mechanical bulk properties are guaranteed by the presence of reinforcing fibers, in vitro and in vivo performances of these materials are ultimately driven by their ability to establish proper interactions between their surface and the surrounding tissues. Hence, the development of novel chemical processes enabling the introduction of bioactive molecules on the surface of these methacrylate-based thermosets is of particular interest. In the present work, we have devised a chemical strategy to expose carboxylic groups on the surface of the BisGMA/TEGDMA thermoset. The presence of negative charges was confirmed by Fourier transform infrared-attenuated total reflectance and by UV-vis spectrophotometry. Bulk mechanical properties and surface morphology of the thermoset were only slightly affected upon chemical functionalization. The activated material was further refined by the deposition of a lactose-modified chitosan (chitlac) driven by strong electrostatic interactions. The presence of the bioactive polysaccharide was confirmed by fluorescence spectroscopy and by confocal laser scanning microscopy measurements. Scratch tests were performed to evaluate the mechanical behavior of the coating. Finally, in vitro tests revealed that the presence of chitlac led to a slight enhancement of cell proliferation with respect to the unmodified BisGMA/TEGDMA thermoset. This effect was more pronounced when chitlac decorated with an arginine-glycine-aspartic acid (RGD) peptide was used in the preparation of the coating. In the latter case, the in vitro performance of the coated BisGMA/TEGDMA thermoset became comparable with that of clinically used roughened titanium.
双酚 A 缩水甘油甲基丙烯酸酯 (BisGMA)/三乙二醇二甲基丙烯酸酯 (TEGDMA) 热固性塑料和复合材料是牙科应用中众所周知的生物材料实例，它们在骨科应用中越来越受到关注。虽然增强纤维的存在保证了机械整体性能，但这些材料的体外和体内性能最终取决于其在表面与周围组织之间建立适当相互作用的能力。因此，开发能够在这些甲基丙烯酸酯基热固性塑料表面引入生物活性分子的新型化学工艺具有特别的意义。在本工作中，我们设计了一种在 BisGMA/TEGDMA 热固性塑料表面暴露羧酸基团的化学策略。傅里叶变换红外衰减全反射和紫外-可见分光光度法证实了存在负电荷。化学官能化仅对热固性塑料的体机械性能和表面形貌略有影响。通过强静电相互作用驱动的乳糖修饰壳聚糖 (chitlac) 的沉积进一步对活化材料进行细化。荧光光谱和共聚焦激光扫描显微镜测量证实了生物活性多糖的存在。进行划痕测试以评估涂层的机械性能。最后，体外测试表明，与未修饰的 BisGMA/TEGDMA 热固性塑料相比，chitlac 的存在导致细胞增殖略有增强。当用于制备涂层的 chitlac 用精氨酸-甘氨酸-天冬氨酸 (RGD) 肽修饰时，这种效果更为明显。在后一种情况下，涂覆的 BisGMA/TEGDMA 热固性塑料的体外性能变得与临床使用的粗糙钛相当。
