Tissue Engineering Laboratory, Department of Biomedical Engineering, Jinan University, Guangzhou, 510630, People's Republic of China.
Biomed Mater. 2010 Dec;5(6):065016. doi: 10.1088/1748-6041/5/6/065016. Epub 2010 Nov 15.
Both chitosan and polylactide/polyglycolide have good biocompatibility and can be used to produce tissue engineering scaffolds for cultured cells. However the synthetic scaffolds lack groups that would facilitate their modification, whereas chitosan has extensive active amide and hydroxyl groups which would allow it to be subsequently modified for the attachment of peptides, proteins and drugs. Also chitosan is very hydrophilic, whereas PLGA is relatively hydrophobic. Accordingly there are many situations where it would be ideal to have a copolymer of both, especially one that could be electrospun to provide a versatile range of scaffolds for tissue engineering. Our aim was to develop a novel route of chitosan-g-PLGA preparation and evaluate the copolymers in terms of their chemical characterization, their performance on electrospinning and their ability to support the culture of fibroblasts as an initial biological evaluation of these scaffolds. Chitosan was first modified with trimethylsilyl chloride, and catalyzed by dimethylamino pyridine. PLGA-grafted chitosan copolymers were prepared by reaction with end-carboxyl PLGA (PLGA-COOH). FT-IR and(1)H-NMR characterized the copolymer molecular structure as being substantially different to that of the chitosan or PLGA on their own. Elemental analysis showed an average 18 pyranose unit intervals when PLGA-COOH was grafted into the chitosan molecular chain. Differential scanning calorimetry results showed that the copolymers had different thermal properties from PLGA and chitosan respectively. Contact angle measurements demonstrated that copolymers became more hydrophilic than PLGA. The chitosan-g-PLGA copolymers were electrospun to produce either nano- or microfibers as desired. A 3D fibrous scaffold of the copolymers gave good fibroblast adhesion and proliferation which did not differ significantly from the performance of the cells on the chitosan or PLGA electrospun scaffolds. In summary this work presents a methodology for making a hybrid material of natural and synthetic polymers which can be electrospun and reacts well as a substrate for cell culture.
壳聚糖和聚乳酸/聚乙二醇具有良好的生物相容性，可用于培养细胞的组织工程支架。然而，合成支架缺乏有利于其修饰的基团，而壳聚糖具有广泛的活性酰胺和羟基基团，这使得它可以进一步修饰以附着肽、蛋白质和药物。此外，壳聚糖非常亲水，而 PLGA 相对疏水。因此，在许多情况下，拥有两者的共聚物是理想的，特别是可以电纺的共聚物，为组织工程提供各种支架。我们的目标是开发一种壳聚糖-g-PLGA 的制备新途径，并根据其化学特性、电纺性能以及支持成纤维细胞培养的能力来评估共聚物，作为对这些支架的初步生物学评价。首先用三甲基氯硅烷对壳聚糖进行修饰，并用二甲氨基吡啶催化。通过与端羧基 PLGA（PLGA-COOH）反应制备 PLGA 接枝壳聚糖共聚物。FT-IR 和（1）H-NMR 表明共聚物的分子结构与壳聚糖或 PLGA 本身有很大的不同。元素分析表明，当 PLGA-COOH 接枝到壳聚糖分子链上时，平均有 18 个吡喃糖单元间隔。差示扫描量热法结果表明，共聚物具有与 PLGA 和壳聚糖分别不同的热性能。接触角测量表明，共聚物比 PLGA 更亲水。壳聚糖-g-PLGA 共聚物可通过静电纺丝制成所需的纳米或微纤维。共聚物的 3D 纤维支架为成纤维细胞提供了良好的粘附和增殖能力，与细胞在壳聚糖或 PLGA 静电纺丝支架上的性能没有显著差异。总之，这项工作提出了一种制造天然和合成聚合物的混合材料的方法，该材料可以静电纺丝，并且很好地作为细胞培养的底物。
