Experimental Study Of Surface Modification On PEEK Implant Material

Objective:In this study, PEEK implant material was modified by nitrogen plasma immersion ion implantation to obtain nano-modified layer and nitrogen functional groups structure on the surface of PEEK. The bioactivity and antibacterial of PEEK were investigated through a series of in vitro tests. Based on this, the optimal modified parameters could be selected, providing reliable scientific basis for the wide application of PEEK in the field of medical implant. Methods:According to the different modified parameters, the PEEK specimens were randomly divided into control group, immersion group, low pulse group and high pulse group. And then they were treated with N2-PIII surface modification under the corresponding parameters, respectively. The microstructure and composition of the modified PEEK surface were observed by SEM, atomic force microscopy(AFM) and X-ray photoelectron spectroscopy(XPS), respectively. The water contact angle of PEEK surface was also studied by contact angle meters. The osteoblast-like cell viability of PEEK samples was evaluated by observing the attachment, proliferation and differentiation of MG63 cells cultured on the PEEK samples. Antibacterial properties of samples against staphylococcus aureus were detected with the plate colonycounting methods. Results:SEM and AFM analysis showed that the specimen surface of control group was relatively smooth. Immersion group and low pulse group PEEK had a rough surface with nano-protrusions structure. The high pulse group PEEK surface became much rougher and represented any columnar structure. XPS element analysis showed that nitrogen functional groups were successfully introduced into the N2-PIII modified PEEK surface. Biological evaluation and the antibacterial results showed that, the biological activity of PEEK was significantly improved and it showed a certain antibacterial properties toward Staphylococcus aureus after nitrogen PIII modification. Conclusions:After Nitrogen PIII modification, the PEEK displayed the nanoscale morphology and nitrogenous organic functional groups were obtained on its surface. Meanwhile, the biological activity and antibacterial property of PEEK were enhanced.