Zhu Wenkun, Chen Tao, Li Yi, Lei Jia, Chen Xin, Yao Weitang, Duan Tao
State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang 621010, China.
Engineering Research Center of Biomass Materials, Ministry of Education, Mianyang 621010, China.
Materials (Basel). 2017 May 16;10(5):536. doi: 10.3390/ma10050536.
This study was inspired by the unique multi-scale and multi-level 'brick-and-mortar' (B&M) structure of nacre layers. We prepared the B&M, environmentally-friendly graphene oxide-carrageenan (GO-Car) nanocomposite films using the following steps. A natural polyhydroxy polymer, carrageenan, was absorbed on the surface of monolayer GO nanosheets through hydrogen-bond interactions. Following this, a GO-Car hybridized film was produced through a natural drying process. We conducted structural characterization in addition to analyzing mechanical properties and cytotoxicity of the films. Scanning electron microscope (SEM) and X-ray diffraction (XRD) analyses showed that the nanocomposite films had a similar morphology and structure to nacre. Furthermore, the results from Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and Thermogravimetric (TG/DTG) were used to explain the GO-Car interaction. Analysis from static mechanical testers showed that GO-Car had enhanced Young's modulus, maximum tensile strength and breaking elongation compared to pure GO. The GO-Car nanocomposite films, containing 5% wt. of Car, was able to reach a tensile strength of 117 MPa. The biocompatibility was demonstrated using a RAW264.7 cell test, with no significant alteration found in cellular morphology and cytotoxicity. The preparation process for GO-Car films is simple and requires little time, with GO-Car films also having favorable biocompatibility and mechanical properties. These advantages make GO-Car nanocomposite films promising materials in replacing traditional petroleum-based plastics and tissue engineering-oriented support materials.
本研究受珍珠层独特的多尺度和多层次“实体”（B&M）结构启发。我们通过以下步骤制备了具有环境友好性的氧化石墨烯-角叉菜胶（GO-Car）纳米复合薄膜。天然多羟基聚合物角叉菜胶通过氢键相互作用吸附在单层氧化石墨烯纳米片表面。随后，通过自然干燥过程制备出GO-Car杂交薄膜。除了分析薄膜的机械性能和细胞毒性外，我们还进行了结构表征。扫描电子显微镜（SEM）和X射线衍射（XRD）分析表明，纳米复合薄膜具有与珍珠层相似的形态和结构。此外，利用傅里叶变换红外光谱（FT-IR）、拉曼光谱、X射线光电子能谱（XPS）和热重分析（TG/DTG）的结果来解释GO-Car之间的相互作用。静态力学测试分析表明，与纯氧化石墨烯相比，GO-Car的杨氏模量、最大拉伸强度和断裂伸长率均有所提高。含有5%（重量）角叉菜胶的GO-Car纳米复合薄膜能够达到117MPa的拉伸强度。通过RAW264.7细胞测试证明了其生物相容性，细胞形态和细胞毒性均未发现明显变化。GO-Car薄膜的制备过程简单且耗时少，同时还具有良好的生物相容性和机械性能。这些优点使GO-Car纳米复合薄膜成为替代传统石油基塑料和组织工程支撑材料的有前途的材料。
