Applied Biotechnology Research Group, Department of Molecular & Applied Biosciences, University of Westminster, London W1W 6UW, United Kingdom.
Applied Biotechnology Research Group, Department of Molecular & Applied Biosciences, University of Westminster, London W1W 6UW, United Kingdom.
Carbohydr Polym. 2014 Nov 26;113:131-7. doi: 10.1016/j.carbpol.2014.07.003. Epub 2014 Jul 11.
Bacterial cellulose (BC) exhibits high purity, mechanical strength and an ultra-fine fibrous 3-D network structure with bio-compatible and bio-degradable characteristics, while P(3 HB) are a bio-degradable matrix material derived from natural resources. Herein, we report a mild and eco-friendly fabrication of indigenously isolated P(3 HB) based novel composites consisting of BC (a straight-chain polysaccharide) as a backbone polymer and laccase was used as a grafting tool. The resulting composites were characterised by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), dynamic mechanical analyser (DMA) and water contact angle analyser (WCA). The FTIR spectra of the pure P(3 HB) and P(3 HB) containing graft composites [P(3 HB)-g-BC] showed their strong characteristic bands at 3358 cm(-1), 1721 cm(-1) and 1651 cm(-1), respectively. A homogenous dispersion of P(3 HB) in the backbone polymer of BC was achieved as evident by the SEM micrographs. XRD pattern for P(3 HB) showed distinct peaks at 2θ values that represent the crystalline nature of P(3 HB). While, in comparison with those of neat P(3 HB), the degree of crystallinity for P(3 HB)-g-BC decreased and this reduction is mainly because of the new cross-linking of P(3 HB) within the backbone polymer that changes the morphology and destroys the crystallites. Laccase-assisted graft composite prepared from P(3 HB) and BC was fairly flexible and strong, judged by the tensile strength (64.5 MPa), elongations at break (15.7%), and Young's modulus (0.98 GPa) because inherently high strength of BC allowed the mechanical properties of P(3 HB) to improve in the P(3 HB)-g-BC composite. The hydrophilic property of the P(3 HB)-g-BC was much better than that of the individual counterparts which is also a desired characteristic to enhance the biocompatibility of the materials for proper cell adhesion and proliferation.
细菌纤维素 (BC) 具有高纯度、机械强度和超精细的纤维 3D 网络结构，具有生物相容性和可生物降解的特点，而 P(3 HB) 则是一种源自天然资源的可生物降解基质材料。在此，我们报告了一种温和且环保的制备方法，可制备由细菌纤维素 (一种直链多糖) 作为主链聚合物和漆酶作为接枝工具的新型复合材料。所得复合材料的特征在于傅里叶变换红外光谱 (FTIR)、扫描电子显微镜 (SEM)、X 射线衍射 (XRD)、差示扫描量热法 (DSC)、动态机械分析器 (DMA) 和水接触角分析器 (WCA)。纯 P(3 HB) 和含有接枝复合材料 [P(3 HB)-g-BC] 的 P(3 HB) 的 FTIR 光谱在 3358 cm(-1)、1721 cm(-1) 和 1651 cm(-1) 处分别显示出其强特征带。SEM 照片表明，P(3 HB) 在 BC 主链聚合物中的均匀分散。P(3 HB) 的 XRD 图谱在 2θ 值处显示出明显的峰，代表 P(3 HB) 的结晶性质。然而，与纯 P(3 HB) 相比，P(3 HB)-g-BC 的结晶度降低，这种降低主要是因为 P(3 HB) 在内的新交联在主链聚合物中，改变了形态并破坏了晶体。通过拉伸强度 (64.5 MPa)、断裂伸长率 (15.7%) 和杨氏模量 (0.98 GPa) 判断，漆酶辅助接枝复合材料由 P(3 HB) 和 BC 制备而成，其具有相当的柔韧性和强度，因为 BC 固有的高强度允许 P(3 HB) 的机械性能在 P(3 HB)-g-BC 复合材料中得到提高。P(3 HB)-g-BC 的亲水性比单个对应物要好得多，这也是增强材料生物相容性以促进适当细胞粘附和增殖的理想特性。
