From design of bio-based biocomposite electrospun scaffolds to osteogenic differentiation of human mesenchymal stromal cells

Abstract

Electrospinning coupled with electrospraying provides a straightforward and robust route toward promising electrospun biocomposite scaffolds for bone tissue engineering. In this comparative investigation, four types of poly(3-hydroxybutyrate) (PHB)-based nanofibrous scaffolds were produced by electrospinning a PHB solution, a PHB/gelatin (GEL) mixture or a PHB/GEL/nHAs (hydroxyapatite nanoparticles) mixed solution, and by electrospinning a PHB/GEL solution and electrospraying a nHA dispersion simultaneously. SEM and TEM analyses demonstrated that the electrospun nHA-blended framework contained a majority of nHAs trapped within the constitutive fibers, whereas the electrospinning-electrospraying combination afforded fibers with a rough surface largely covered by the bioceramic. Structural and morphological characterizations were completed by FTIR, mercury intrusion porosimetry, and contact angle measurements. Furthermore, an in vitro investigation of human mesenchymal stromal cell (hMSC) adhesion and proliferation properties showed a faster cell development on gelatin-containing scaffolds. More interestingly, a long-term investigation of hMSC osteoblastic differentiation over 21 days indicate that hMSCs seeded onto the nHA-sprayed scaffold developed a significantly higher level of alkaline phosphatase activity, as well as a higher matrix biomineralization rate through the staining of the generated calcium deposits: the fiber surface deposition of nHAs by electrospraying enabled their direct exposure to hMSCs for an efficient transmission of the bioceramic osteoinductive and osteoconductive properties, producing a suitable biocomposite scaffold for bone tissue regeneration.

Controlled release of drugs in electrosprayed nanoparticles for bone tissue engineering

“…These which are loaded with 4% HA nanoparticles on the surface using electrospray method, in order to enhance cell adhesion, interaction, proliferation, migration and differentiation for bone tissue regeneration [37]. PCL nanofibers are electrospun on the rotating drum together with n-HA particles (52 nm) electrosprayed on them to get diameters of 420 ± 15 nm.…”

Electrospinning and electrospraying techniques for designing novel antibacterial poly(3-hydroxybutyrate)/zinc oxide nanofibrous composites

“…Electrospun nanofibrous scaffolds exhibit highly porous structures with fiber diameters suitable to mimic the natural extracellular matrix, thus promoting cell attachment and proliferation [1][2][3][4]. Nonetheless, these morphological features entail a huge inconvenient, namely, the adhesion of pathogenic microorganisms [5][6][7].…”

“…Several strategies have been developed in order to overcome this problematic issue, being the most prominent the incorporation of organic compounds [8], and more recently, metallic nanoparticles [9][10][11][12] with well-recognized antimicrobial properties. Electrospun polymer composites containing these specific nanoparticles can exhibit several advantages compared to typical organic compound-loaded polymers, such as higher thermal stability, enhanced mechanical performance or biocompatibility, depending on the chemical nature of nanoparticles [1,2,[12][13][14][15].…”

Biodegradable polymeric nanomaterials

“…This natural polyester can be produced biotechnologically leading to a high semi-crystalline polymer (Tm = 168-182 °C, Tg = 1-15 °C). PHB could be used for various applications in the biomedical field due to its biocompatibility and biodegradability, as well as the non-cytotoxicity of its metabolic products [18]. Indeed, PHB degradation leads to D-(−)-3-hydroxy-butyric acid, which is a normal constituent of blood.…”

“…In contrast, when the hydroxyapatite nanoparticles were sprayed over the PHB nanofibres during the electrospinning process, the mechanical properties drastically decreased. This can be attributed to the higher porosity of the scaffold due to weaker interactions between the fibres and the hydroxyapatite nanoparticles [18]. Nanofibrous scaffolds obtained by TIPS exhibit significantly better mechanical behaviour than solid-walled porous scaffolds [50].…”