A remote atmospheric pressure plasma-assisted textile functionalization process on polymeric scaffolds for bone tissue engineering

Abstract

When adopting polylactic acid (PLA) nonwoven for bone tissue engineering scaffolds, the inert and hydrophobic nature of PLA leads to poor biocompatibility and osteoconductivity, and limits the efficiency of applying bioceramic coatings, such as hydroxyapatite (HAp), for surface functionalization. To tackle these issues, a remote atmospheric pressure plasma (APP) system using a bespoke Pyrex chamber and acrylic acid monomer was designed and employed to functionalize the PLA via depositing carboxylic acid functional groups onto its surface. The remote APP showed being polymeric textile-suitable with an improved efficiency on not only immobilizing carboxylic acid functional groups on the PLA nonwoven than conventional systems but also the alternate soaking process for HAp deposition. Being compared with the neat PLA, the plasma-functionalized PLA exhibited a more hydrophilic surface (from 130.49 ± 1.28° to 117.40 ± 2.53°) with a 30-day stability (from 117.40 ± 2.53° to 119.40 ± 0.75°) and showed better biocompatibility (136 % to the neat PLA) with MC3T3-E1 mouse embryonic osteoblast cells after HAp deposition. The presence of carboxylic acid functional groups and HAp (Ca/P ratio of 1.7) was also identified using X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy and a scanning electron microscope with energy dispersive X-ray analysis.