Controllable fabrication of multi-modal porous PLGA scaffolds with different sizes of SPIONs using supercritical CO2 foaming

Multi-modal porous scaffolds can promote bone regeneration. In the present study, they were successfully fabricated from poly (lactic-co-glycolic acid) (PLGA)/superparamagnetic iron oxide nanoparticles (SPIONs) by supercritical CO 2 foaming, where SPIONs was employed as heterogeneous nucleation agent. The effects of SPION size on pore nucleation in PLGA/SPIONs nanocomposites were investigated. It was found that the addition of smaller SPIONs size caused the reduction of pore size. Multi-modal porous scaffolds could be available by controlling the SPIONs content, soaking temperature, pressure, and depressurization rate. The porosity of the PLGA/SPIONs scaffolds ranged from (58.68 ± 0.62)% to (94.97 ± 0.14)% could be obtained via adjusting the supercritical CO 2 foaming conditions. Moreover, it was found that the compressive modulus and porosity of the scaffolds were strongly associated with the porous structure. This study provided a new green preparation method for magnetic scaffolds to realize the controllable adjustment of the multi-mode porous scaffolds.