Research Center for Pharmaceutical Nanotechnology, Tabriz University of Medical Sciences, Tabriz, Iran.
Organosilicon Research Laboratory, Faculty of Chemistry, University of Tabriz, Tabriz, Iran.
Biomed Mater. 2022 Oct 14;17(6). doi: 10.1088/1748-605X/ac94ad.
Biocompatible hydrogels are promising approaches for bone repair and engineering. A novel therapeutic nanocomposite hydrogel was designed based on triblock copolymer poly e-caprolactone (PCL)-polyethylene glycol-PCL and natural gelatin (PCEC/GEL) and reinforced with halloysite nanotube (HNT). Gentamicin (GM) loaded HNT was immobilized in polymeric hydrogel matrix to fabricate scaffolds using the freeze-drying method. Scaffolds were characterized via Fourier transform infrared (FT-IR), x-ray powder diffraction, and scanning electron microscope (SEM) methods. The swelling ratio, density, porosity, degradation, and mechanical behavior were evaluated to investigate the effects of HNT on the physicochemical properties of the composite. Cell viability and cell attachment were investigated by microculture tetrazolium (MTT) assay and SEM. Cell proliferation was observed without any cytotoxicity effect on human dental pulp-derived mesenchymal stem cells (h-DPSCs). Alizarin red staining and real-time reverse transcription polymerase chain reaction (QRT-PCR) assay were carried out to monitor the osteoconductivity of scaffolds on h-DPSCs which were seeded drop wise onto the top of scaffolds. The quantification of the messenger RNA (mRNA) expression of osteogenic marker genes, bone morphogenetic protein 2, SPARK, bone gamma-carboxyglutamate protein and runt-related transcription factor 2 over a period of 21 d of cell seeding, demonstrated that cell-encapsulating PCEC/GEL/HNT-GM hydrogel scaffolds supported osteoblast differentiation of h-DPSCs into osteogenic cells through the up-regulation of related genes along with moderate effects on cell viability. Moreover, the antibiotics loading reduced bacterial growth while maintaining the osteogenic properties of the scaffold. Therefore, the bactericidal PCEC/GEL/HNT-GM hydrogel nanocomposite, with enhanced durability, maintenance the functionality of seeded cellsthat can be a remarkable dual-functional candidate for hard tissue reconstruction and customized bone implants fabrication via the direct incorporation of bactericidal drug to prevent infection.
生物相容性水凝胶是修复和工程骨的有前途的方法。设计了一种基于三嵌段共聚物聚己内酯（PCL）-聚乙二醇-PCL 和天然明胶（PCEC/GEL）的新型治疗性纳米复合水凝胶，并通过埃洛石纳米管（HNT）进行增强。将负载庆大霉素（GM）的 HNT 固定在聚合物水凝胶基质中，使用冷冻干燥法制备支架。通过傅里叶变换红外（FT-IR）、X 射线粉末衍射和扫描电子显微镜（SEM）方法对支架进行了表征。评估了溶胀比、密度、孔隙率、降解和机械性能，以研究 HNT 对复合材料物理化学性质的影响。通过微量培养四唑（MTT）测定法和 SEM 研究了细胞活力和细胞附着。观察到对人牙髓间充质干细胞（h-DPSCs）没有细胞毒性作用的细胞增殖。通过茜素红染色和实时逆转录聚合酶链反应（QRT-PCR）分析来监测支架在 h-DPSCs 上的成骨能力，h-DPSCs 以滴注的方式接种在支架的顶部。在细胞接种后的 21 天内，对成骨标志物基因骨形态发生蛋白 2、SPARK、骨 γ-羧基谷氨酸蛋白和 runt 相关转录因子 2 的信使 RNA（mRNA）表达进行定量，结果表明，细胞包封的 PCEC/GEL/HNT-GM 水凝胶支架通过上调相关基因支持 h-DPSCs 向成骨细胞分化为成骨细胞，同时对细胞活力有适度影响。此外，抗生素负载减少了细菌生长，同时保持了支架的成骨特性。因此，载有抗生素的杀菌 PCEC/GEL/HNT-GM 水凝胶纳米复合材料具有增强的耐久性，维持了接种细胞的功能，可作为一种显著的双重功能候选物，用于通过直接掺入杀菌药物来预防感染的硬组织重建和定制骨植入物的制造。
