Design Redox-Sensitive Drug-Loaded Nanofibers for Bone Reconstruction

Abstract

Implantation of a scaffold into the body in a safe and convenient manner remains a challenge in the repair of patient bone defect. In the present study, a strategy for fabrication of the redox-sensitive nanofibers with a core−shell structure that can deliver the growth factors in a tunable manner is presented. Poly(ethylene oxide) (PEO) and bone morphogenetic protein 2 (BMP-2) forms the inner core region, and a mixture of poly(epsilon-caprolactone) (PCL) and redox-responsive c-6A PEG−PCL nanogel with −S−S− bond forms the outer shell. The redox-sensitive shell of the nanofibers can respond the change of the GSH (glutathione) concentration and thus regulate the BMP-2 release behavior in vitro and in vivo. In vitro cytotoxicity results indicated that the redox-sensitive nanofiber had good osteoinduction. The in vivo results demonstrated that the nanofibers exhibited a capacity of prompting new bone generation in the bone defect. Therefore, the redox-responsive nanofiber in the present study may be of great potential for application in bone reconstruction.

Stimuli‐Responsive Delivery of Growth Factors for Tissue Engineering

“…Gong et al engineered novel, redox‐responsive, core–shell structured fibers for controlled release of BMP‐2 for mandibular bone defect regeneration ( Figure ). [ 111 ] BMP‐2 was encapsulated in the core region with Poly(ethylene oxide) (PEO), and the outer shell was composed of poly(ε‐caprolactone) (PCL) and redox‐responsive nanogels (crosslinked 6‐arm PEG‐polycaprolactone/6‐arm PEG‐polycaprolactone‐sulfhydryl nanogels, c‐6A PEG‐PCL/6A PEG‐PCL‐SH NGs). The degradation of nanogels was controlled by GSH levels resulting in the formation of nanochannels inside the nanogel and increasing shell permeability and drug release from the inner region.…”

“…ROS responsive nanofiber for BMP‐2 delivery with core–shell structure designed for bone regeneration. [ 111 ] A) Schematic of the fabrication of the nanogel‐in‐nanofiber device and the ROS responsive delivery via ROS‐induced degradation of the nanogel and the nanochannels formed to promote the diffusion rate of BMP‐2 loaded in the core of nanofiber. B) TEM images of nanogel.…”

Recent Developments in Nanofiber Fabrication and Modification for Bone Tissue Engineering

“…The processes after that are similar to a conventional electrospinning, in which a collector is used to carry fibers. Co-axial electrospinning permits various materials, including polymers [46,47], oligomers [48], inorganic compounds [37], proteins [47], and biomolecules [41], to be immobilized into the core component of the core-shell nanofibers. Due to the functions of the core component, the core-shell nanofiber has more beneficial properties for bone tissue engineering.…”

“…Gong et al demonstrated drug delivery by nanofibers for bone regeneration. Poly(ethylene oxide) (PEO) containing bone morphogenetic protein 2 (BMP-2) was used as the inner core and poly-ε-caprolactone (PCL) was used as the outer shell [47]. Shalumon et al fabricated silk fibroin (SF)/chitosan (CS)/nanohydroxyapatite (nHAP) nanofibers embedded with BMP-2 in the core of the nanofiber [50].…”

Producing 3D Biomimetic Nanomaterials for Musculoskeletal System Regeneration

“…(B) Table-top SLA method to obtain porous hydrogel-based scaffolds that emulate the transitional nature of the osteochondral region by the inclusion of a gradient of nHA (adapted from Castro et al, 2015 , with permission from The Royal Society of Chemistry). (C) Redox-responsive nanofibers allow the controlled BMP-2 release for bone regeneration in rat model (reprinted with permission from Gong et al, 2018 , copyright American Chemical Society).…”