Construction And Performance Evaluation Of A Sustained Release Implant Material PEEK With Antibacterial Properties

Objective:In this study,argon plasma low-temperature modification technology was used to prepare polyetheretherketone(PEEK)with nano topological morphology.Van-GNPs was prepared by two-step desolvation method,its physical properties.With the aid of polydopamine(PDA)characteristic of"wet binding",the Implant Drug Delivery System(IDDS)with strongbond and sustainable release of antibiotics was established on the surface of PEEK bone Implant material by physical and chemical interaction,in vitro release of antibiotics were evaluated and the evaluation method of the bond strength between various elements was established.The biological properties and application prospects of the composite materials were evaluated by cell and bacteria models,which will lay a theoretical foundation for the extensive clinical application of PEEK implant materials.Methods:PEEK with nano topological morphology was prepared by argonplasma modification at low temperature under certain parameters.PDA coating was formed on PEEK surface by chemical deposition method,and a biological platform with strong binding properties was constructed.The microstructure of the material was observed by scanning electron microscopy(SEM).The roughness of the material surface was observed by atomic force microscope(AFM).The water contact Angle on the material surface is detected by the contact Angle tester.Vancomycin gelatin nanoparticles(Van-GNPs)were prepared by two-step desolvation method.The morphology and structure of the nanoparticles were observed and analyzed by SEM.Nano measurer 1.2 software were used to calculate the particle size distribution range,and the encapsulation rate and drug loading rate of Van-GNPs were measured.Van-GNPs was combined with PEEK implantation material to form a composite material,and its surface element composition,microscopic morphology,roughness and contact Angle were comprehensively analyzed.The release test of vancomycin in vitro was carried out by dynamic dialysis method with the aid of ultraviolet spectrophotometer.The composite material extract was co-cultured with mouse embryonic osteoblasts(MC-3T3),and the cytotoxicity of the material was detected by CCK-8 reagent.MC-3T3 cells were co-cultured with the material,and the adhesion of cells on the material surface was observed by SEM.The composite was co-cultured with staphylococcus aureus and streptococcus mutans,and the bacterial adhesion on the surface of the material was detected by SEM and plate colony counting method.Results:(1)With the modification of argon plasma at low temperature,PEEK has formed a nano-topological structure and its surface roughness has been increased.PDA was uniformly applied on the PEEK surface modified by argon plasma at low temperature.(2)Van-GNPs has a smooth and round surface with particle size distribution between 180nm and 290nm,and its encapsulation rate and drug loading rate are 70.5%and 10.3%,respectively.(3)Van-GNPs binds with PEEK to form a new composite material,which can release vancomycin in vitro for more than 15 days.(4)Cell experiments showed that the new PEEK composite had no cytotoxicity and had good interaction with osteoblasts.Bacterial experiments showed that surface conjugation with Van-GNPs could signi:ficantly improve the antibacterial performance of PEEK against staphylococcus aureus and streptococcus mutans.Conclusions:(1)PEEK was modified with argon plasma at low temperature and then combined with polydopamine to construct a biological platform with strong binding properties on PEEK surface.(2)Van-GNPs with smooth,stable surface and slow-release properties can be prepared by two-step desolvation.(3)The combination of Van-GNPs and PEEK resulted in the new implant-grade composite has good cellular compatibility and significantly improves the antibacterial properties of PEEK.