Super-paramagnetic responsive nanofibrous scaffolds under static magnetic field enhance osteogenesis for bone repair in vivo

Abstract

A novel nanofibrous composite scaffold composed of super-paramagnetic γ-Fe2O3 nanoparticles (MNP), hydroxyapatite nanoparticles (nHA) and poly lactide acid (PLA) was prepared using electrospinning technique. The scaffold well responds extern static magnetic field with typical saturation magnetization value of 0.049 emu/g as well as possesses nanofibrous architecture. The scaffolds were implanted in white rabbit model of lumbar transverse defects. Permanent magnets are fixed in the rabbit cages to provide static magnetic field for the rabbits post surgery. Results show that MNP incorporated in the nanofibers endows the scaffolds super-paramagnetic responsive under the applied static magnetic field, which accelerates new bone tissue formation and remodeling in the rabbit defect. The scaffold also exhibits good compatibility of CK, Cr, ALT and ALP within normal limits in the serum within 110 days post implantation. In conclusion, the super-paramagnetic responding scaffold with applying of external magnetic field provides a novel strategy for scaffold-guided bone repair.

Harnessing magnetic-mechano actuation in regenerative medicine and tissue engineering

“…The methods for incorporation of magnetic particles in biomaterials include doping, blending, in situ precipitation, and the 'graftingonto' method [89]. For the purposes of tissue engineering, a material is considered to have satisfactory magnetic properties if magnetic saturation values are above 0.049 emu/g [90].…”

Visualization of Magnetic Nanofibers Using Magnetic Particle Imaging

“…Weak magnetic or pulse electromagnetic fields of Gauss order have been reported to be effective for promoting bone fracture healing and spinal fusion [3]. Strong static magnetic fields of 5 to 10 Tesla have also been reported to potently regulate the orientation of matrix proteins and cells in vitro and in vivo [3]. Meng et al [3] reported that the magnetic scaffold under a static magnetic field enhanced osteogenesis and provided a novel strategy for scaffold-guided bone repair.…”

“…Besides these mechanical stimuli, magnetic stimulation originating from static or alternating magnetic fields has also attracted researchers' interest [3]. Weak magnetic or pulse electromagnetic fields of Gauss order have been reported to be effective for promoting bone fracture healing and spinal fusion [3]. Strong static magnetic fields of 5 to 10 Tesla have also been reported to potently regulate the orientation of matrix proteins and cells in vitro and in vivo [3].…”

“…Besides these mechanical stimuli, magnetic stimulation originating from static or alternating magnetic fields has also attracted researchers' interest [3]. Weak magnetic or pulse electromagnetic fields of Gauss order have been reported to be effective for promoting bone fracture healing and spinal fusion [3].…”

Electrospun nanofiber tubes with elastomagnetic properties for biomedical use

“…In particular, magnetically functionalized nanofibers (MFNs), namely polymer based fibers incorporating magnetic nanoparticles (MNPs), are attracting increasing interest due to their potential use in micro-electro-mechanical devices, magnetic recording, ferrofluids, sensors, microwave absorption [7][8][9][10][11] and biomedical applications -i.e. bone repair [12][13][14], tissue engineering [15,16], magnetic hyperthermia [17], contrast agent and imaging techniques [18][19][20], controlled drug release [21] and drug delivery [22].…”