Nowadays, the development of drug-loaded electrospun organic-inorganic composite scaffolds for tissue engineering application is an attractive approach. In this study, a composite scaffold of Poly-l-lactic acid (PLLA) incorporated dexamethasone (Dexa) loaded Mesoporous Silica Nanoparticles (MSN) coated with Chitosan (CS) were fabricated by electrospinning for bone tissue engineering application. The MSN was prepared by precipitation method. After that, Dexamethasone (Dexa) was loaded into MSNs (MSN-Dexa). In the following, CS was coated over the prepared nanoparticles to form MSN-Dexa@CS and then, were mixed to PLLA solution to form MSN-Dexa@CS/PLLA composite for electrospinning. The surface morphology, hydrophilicity, tensile strength and the bioactivity of the scaffolds were characterized. The osteogenic proliferation and differentiation potential were evaluated by MTT assay and by measuring the basic osteogenic markers: the activity of the enzyme alkaline phosphatase and the level of calcium deposition. The composite scaffolds prepared here have conductive surface property and have a better osteogenic potential than pure PLLA scaffolds. Hence, the controlled release of nanoparticle containing Dexa from composite scaffold supported the osteogenesis and made the composite scaffolds ideal candidates for bone tissue engineering application and pH-sensitive delivery of drugs at the site of implantation in tissue regeneration.

中文翻译：

---

聚-1-乳酸支架结合了壳聚糖包被的介孔二氧化硅纳米粒子，作为pH敏感复合物，可通过地塞米松递送增强人脂肪组织干细胞的成骨分化。

如今，开发用于组织工程的载药静电纺丝有机-无机复合支架是一种有吸引力的方法。在这项研究中，通过静电纺丝制备了一种复合支架，该复合支架由地衣聚糖（CS）包裹的地塞米松（Dexa）负载的地塞米松（Dexa）和聚地乳酸（PLLA）组成，用于骨组织工程应用。通过沉淀法制备MSN。之后，将地塞米松（Dexa）加载到MSN（MSN-Dexa）中。在下文中，将CS涂覆在制备的纳米颗粒上以形成MSN-Dexa @ CS，然后混合至PLLA溶液中以形成用于电纺丝的MSN-Dexa @ CS / PLLA复合材料。表征了支架的表面形态，亲水性，拉伸强度和生物活性。通过MTT测定和通过测量基本成骨标记物：碱性磷酸酶的活性和钙沉积的水平，评估成骨细胞增殖和分化的潜力。与纯PLLA支架相比，此处制备的复合支架具有导电表面性能，并具有更好的成骨潜力。因此，从复合支架中控制释放的含有Dexa的纳米颗粒支持了成骨作用，并使复合支架成为骨组织工程应用和组织再生中植入部位pH敏感药物递送的理想候选者。与纯PLLA支架相比，此处制备的复合支架具有导电表面性能，并具有更好的成骨潜力。因此，从复合支架中控制释放的含有Dexa的纳米颗粒支持了成骨作用，并使复合支架成为骨组织工程应用和组织再生中植入部位pH敏感药物递送的理想候选者。与纯PLLA支架相比，此处制备的复合支架具有导电表面性能，并具有更好的成骨潜力。因此，从复合支架中控制释放的含有Dexa的纳米颗粒支持了成骨作用，并使复合支架成为骨组织工程应用和组织再生中植入部位pH敏感药物递送的理想候选者。