3D Superelastic Scaffolds Constructed from Flexible Inorganic Nanofibers with Self‐Fitting Capability and Tailorable Gradient for Bone Regeneration

Abstract

Repair of bone defects with irregular shapes or at soft tissue insertion sites faces a huge challenge. Scaffolds capable of adapting to bone cavities, generating stiffness gradients, and inducing osteogenesis are necessary. Herein, a superelastic 3D ceramic fibrous scaffold is developed by assembly of intrinsically rigid, structurally flexible electrospun SiO2 nanofibers with chitosan as bonding sites (SiO2 NF‐CS) via a lyophilization technique. SiO2 NF‐CS scaffolds exhibit excellent elasticity (full recovery from 80% compression), fast recovery rate (>500 mm min−1), and good fatigue resistance (>10 000 cycles of compression) in an aqueous medium. SiO2 NF‐CS scaffolds induce human mesenchymal stem cell (hMSC) elongation and differentiation into osteoblasts. In vivo self‐fitting capability is demonstrated by implanting compressed SiO2 NF‐CS scaffolds into different shaped mandibular defects in rabbits, with a spontaneous recovery and full filling of defects. Rat calvarial defect repair validates enhanced bone formation and vascularization by cell (hMSC) histomorphology analysis. Further, subchondral bone scaffolds with gradations in SiO2 nanofibers are developed, leading to a stiffness gradient and spatially chondrogenic and osteogenic differentiation of hMSCs. This work presents a type of 3D ceramic fibrous scaffold, which can closely match bone defects with irregular shapes or at different implant sites, and is promising for clinical translation.

Moving Electrospun Nanofibers and Bioprinted Scaffolds toward Translational Applications

“…In this regard, 3D scaffolds consisting of nanofibers are of great importance. Recently, 3D aerogels made of short nanofibers and directly expanded 3D nanofibrous scaffolds have been developed for use in tissue repair and regeneration . For example, the Mo Group at Donghua University, China, demonstrated the fabrication of superabsorbent 3D scaffolds from short nanofibers made of a blend of gelatin and poly(lactic acid) (PLA).…”

Magnetic-Electrospinning Synthesis of γ-Fe2O3 Nanoparticle–Embedded Flexible Nanofibrous Films for Electromagnetic Shielding

“…Electrospinning is undoubtedly the most widely used method for preparing nanofibrous films [30,31]. As-spun fibers with fascinating properties, such as large surface areas, high length-to-diameter ratios, flexible surface functionality, tunable surface morphologies, and superior mechanical performances, have recently attracted much attention and have a wide array of potential applications, including for thermal management [32,33], optoelectronics [34,35], sensors [36][37][38], catalysis [39,40], energy storage [41,42], tissue engineering [43], and drug delivery [44,45]. The increasing demand in recent years for the precise preparation of nanofibrous films has accelerated the development of new-concept electrospinning techniques.…”

Removal of Mercury Ions from Aqueous Solutions by Crosslinked Chitosan‐based Adsorbents: A Mini Review

“…The endothermic peak at 257°C is attributed to the thermal decomposition of polyvinyl alcohol in the composite sponge. [97] Figure 4d shows the compressive stress-strain curve of the composite sponge. Results show that the original sponge has a full elasticity and can recover nearly 100 % deformation after stress release.…”