Natarajan Janeni, Madras Giridhar, Chatterjee Kaushik
Centre for Nano Science and Engineering, Department of Chemical Engineering, and Department of Materials Engineering, Indian Institute of Science, C.V. Raman Avenue, Bangalore 560012, India.
ACS Omega. 2017 Sep 30;2(9):5545-5556. doi: 10.1021/acsomega.7b01139. Epub 2017 Sep 7.
We have developed nanocomposites based on galactitol/adipic acid in the molar ratio of 1:1 with different weight percentages of graphene oxide (GO). The objective of this study was to analyze the effect of enhanced physicochemical properties achieved due to the addition of GO to the polymers on cellular responses. The chemical structures of the polymer and composites were confirmed by Fourier transform infrared spectroscopy. Scanning electron microscopy revealed the uniform distribution of GO in the polymers. Differential scanning calorimetry showed no significant variation in the glass-transition temperature of the nanocomposites. Dynamic mechanical analysis demonstrated the increase of Young's modulus with the increase in the addition of GO to the polymer from 0.5 to 1 wt % and a dramatic decrease in modulus with the addition of 2 wt % GO to the polyester. Contact angle analysis illustrated a slight increase in hydrophilicity with the addition of GO to the polyester. Investigations on the hydrolytic degradation and dye release were performed and revealed that the degradation and release decreased with the increase in the weight percentages of GO but increased for 2 wt % GO with the polymer. The rates of degradation and dye release followed first-order and Higuchi kinetics, respectively. The initial in vitro cytocompatibility studies exhibited minimal toxicity. Mineralization studies proved that these nanocomposites stimulated osteogenesis. This study has salient implications for designing biodegradable polymers for use as scaffolds with tailored release.
我们制备了基于半乳糖醇/己二酸（摩尔比为1:1）并添加了不同重量百分比氧化石墨烯（GO）的纳米复合材料。本研究的目的是分析由于向聚合物中添加GO而实现的增强物理化学性质对细胞反应的影响。通过傅里叶变换红外光谱确认了聚合物和复合材料的化学结构。扫描电子显微镜显示GO在聚合物中均匀分布。差示扫描量热法表明纳米复合材料的玻璃化转变温度没有显著变化。动态力学分析表明，随着聚合物中GO添加量从0.5 wt%增加到1 wt%，杨氏模量增加，而向聚酯中添加2 wt% GO时模量急剧下降。接触角分析表明，向聚酯中添加GO后亲水性略有增加。进行了水解降解和染料释放研究，结果表明，随着GO重量百分比的增加，降解和释放减少，但对于添加2 wt% GO的聚合物，降解和释放增加。降解速率和染料释放速率分别遵循一级动力学和Higuchi动力学。最初的体外细胞相容性研究显示毒性极小。矿化研究证明这些纳米复合材料刺激了骨生成。本研究对于设计用作具有定制释放功能支架的可生物降解聚合物具有重要意义。
