Physical and biological properties of electrospun poly(d,l‐lactide)/nanoclay and poly(d,l‐lactide)/nanosilica nanofibrous scaffold for bone tissue engineering

Abstract

Electrospun scaffolds exhibiting high physical performances with the ability to support cell attachment and proliferation are attracting more and more scientific interest for tissue engineering applications. The inclusion of inorganic nanoparticles such as nanosilica and nanoclay into electrospun biopolymeric matrices can meet these challenging requirements. The silica and clay incorporation into polymeric nanofibers has been reported to enhance and improve the mechanical properties as well as the osteogenic properties of the scaffolds. In this work, for the first time, the physical and biological properties of polylactic acid (PLA) electrospun mats filled with different concentrations of nanosilica and nanoclay were evaluated and compared. The inclusion of the particles was evaluated through morphological investigations and Fourier transform infrared spectroscopy. The morphology of nanofibers was differently affected by the amount and kind of fillers and it was correlated to the viscosity of the polymeric suspensions. The wettability of the scaffolds, evaluated through wet contact angle measurements, slightly increased for both the nanocomposites. The crystallinity of the systems was investigated by differential scanning calorimetry highlighting the nucleating action of both nanosilica and nanoclay on PLA. Scaffolds were mechanically characterized with tensile tests to evaluate the reinforcing action of the fillers. Finally, cell culture assays with pre‐osteoblastic cells were conducted on a selected composite scaffold in order to compare the cell proliferation and morphology with that of neat PLA scaffolds. Based on the results, we can convince that nanosilica and nanoclay can be both considered great potential fillers for electrospun systems engineered for bone tissue regeneration.

Poly-l-Lactic Acid (PLLA)-Based Biomaterials for Regenerative Medicine: A Review on Processing and Applications

“…In bone TE, electrospinning has been widely used to produce nanofibrous scaffolds with a structure close to the nanoscale collagen fibers of bone [ 166 ]. Electrospun PLLA scaffolds were produced using a surface modification to direct cellular differentiation to the bone lineage and achieve optimal bone regenerative performances.…”

Synthetic polymers as bone engineering scaffold

“…The process of bone formation occurs independently on separate surfaces and leads to procedures that may change the size, shape, and mass of the bone 29 . Bone has a unique ability to repair itself when the injury is not extensive, chronic, severe, or problematical 30 . Moreover, bones add proper structure, manage mechanical movement, protect organs, and produce blood cells 31 .…”

“…This is due to these NPs having a few fascinating properties, such as low thermal conductivity, chemical inertness, and non‐toxicity. The results suggests that AS and CLO nanoparticles embedded in PLA electrospun matrix created good surroundings for cells development, presumably because the cells had a higher affinity for the substrate 30 . Another study found that adding cellulose nanocrystal (CNC) to the PLA matrix increases the mechanical properties of composite scaffolds while enhancing biocompatibility and nanocomposite scaffolds exhibited higher mechanical and thermal properties than polymer‐only scaffolds.…”

Solution-Based Processing for Scaffold Fabrication in Tissue Engineering Applications: A Brief Review

“…Electrospinning involves the production of continuous fibers from inducing the charged filaments of polymer solutions by using an electric force directed by a highvoltage system equipped with a syringe connected to a metallic needle, a pressure pump, and a grounded stationary or rotating collector [81][82][83]. The liquid solution, pumped into the syringe, flows up to onto a pendent droplet suspended at the needle tip, which is then stretched continuously to form a cone-like structure, called the Taylor cone, while increasing the applied voltage.…”