Poly(L-lactic acid)/poly(ethylene oxide) electrospun scaffold containing dexamethasone-loaded TiO2-alendronate mesoporous nanoparticles utilized for bone tissue engineering application

In this work, asymmetrically poly(L-lactic acid)/poly(ethylene oxide) (PLLA/PEO) electrospun scaffolds were incorporated with novel mesoporous TiO2-alendronate nanoparticles loaded with dexamethasone (Dex-TiO2-ALN). The impact of nanoparticle incorporation on the fibers morphology and mechanical properties of the scaffolds was evaluated using FESEM technique and tensile stress assessments, respectively. After the investigation of the release behavior of the scaffolds, in vitro cell studies were performed employing MTT assay for cell viability assessment. Additionally, alkaline phosphatase (ALP) activity and calcium deposition assays were carried out for the potential determination of the osteogenic differentiation of the fabricated scaffolds on human adipose tissue-derived mesenchymal stem cells (hA-MSCs). The results showed that the incorporation of the nanoparticles decreased the average diameter of the electrospun fibers from 693 nm for the neat PLLA/PEO scaffold to 640 nm and 643 nm for the scaffolds containing TiO2-alendronate (TiO2-ALN) and Dex-TiO2-ALN nanoparticles, respectively. However, the surface morphology of the fibers did not changed significantly. According to the mechanical test results, the maximum strengths at breakpoint were 1.20, 1.27, and 1.28 MPa for the neat PLLA/PEO mat and its TiO2-ALN and Dex-TiO2-ALN-reinforced samples, respectively. The release profile showed an initial burst release around 11% of initial loaded Dex after 72 h, followed by a gradual increase to 38.23% at the end of the release period. Moreover, introducing Dex-TiO2-ALN nanoparticles improved cell viability, ALP activity, and calcium deposition as well as notified the importance of scaffold engineering for biomedical applications. [GRAPHICS] .

Automated summary

Asymmetrically poly(L-lactic acid)/poly(ethylene oxide) (PLLA/PEO) electrospun scaffolds were incorporated with novel mesoporous TiO2-alendronate nanoparticles loaded with dexamethasone (Dex-TiO2-ALN). The incorporation of nanoparticles reduced the diameter of the electrospun fibers, but did not significantly change the surface morphology. Mechanical tests showed improved strength for the samples reinforced with TiO2-ALN and Dex-TiO2-ALN. The release profile of the scaffolds showed an initial burst release followed by a gradual increase, and introducing Dex-TiO2-ALN nanoparticles enhanced cell viability, ALP activity, and calcium deposition.