Rapid construction of polyetheretherketone (PEEK) biological implants incorporated with brushite (CaHPO4·2H2O) and antibiotics for anti-infection and enhanced osseointegration

Polyetheretherketone (PEEK) is an ideal implant material for orthopedic and dental application due to its high biocompatibility and mechanical property. However, biological inertness of PEEK hinders the effective clinical applications in treating bone defect, especially in the situation accompanied by bacterial infection. In this study, a layer-by-layer (LBL) deposition method with controlled cycles was developed to rapidly construct brushite (CaHPO4·2H2O) (CaP) layers containing gentamicin sulfate (GS) on PEEK to obtain CaP-and-GS modified PEEK, named as PEEK/CaP-GS. Different PEEK/CaP-GS, like PEEK/CaP-GS*3, PEEK/CaP-GS*6 and PEEK/CaP-GS*9 were conveniently prepared by repeating the LBL cycles to 3, 6 and 9 times, respectively. The morphology, structure and surface property of the fabricated PEEK/CaP-GS were carefully characterized. In vitro antibacterial experiments illustrated that all of the PEEK/CaP-GS samples had excellent and sustained antibacterial property. Cell proliferation experiments revealed the acceptable biocompatibility and cell osteogenic differentiation of PEEK/CaP-GS, especially in PEEK/CaP-GS*6. X-ray, μ-CT, and histological analysis showed that PEEK/CaP-GS exhibited in vivo antibacterial activity and osseointegration ability in the treatment of bone defect with infection. In both the in vitro and the in vivo experiments, PEEK/CaP-GS*6 prepared from the 6 LBL cycles exhibited the best antibacterial and osseointegration ability for bone healing. This work opens new avenue of the facile and effective modification of PEEK with special biological functions for clinical application, especially for the implants requiring excellent antibacterial and osseointegration ability. In this work, a layer-by-layer (LBL) method with controlled cycles was designed to rapidly construct brushite (CaHPO4·2H2O) (CaP) layers containing gentamicin sulfate (GS) on PEEK to obtain CaP-and-GS modified PEEK (PEEK/CaP-GS). In vitro and in vivo experiments were carried out to evaluate the excellent performance of antibacterial and osseointegration ability of designed PEEK/CaP-GS for bone healing. [Display omitted] •A layer-by-layer (LBL) deposition method with controlled cycles was developed to modify PEEK•Brushite (CaP) and gentamicin (GS) modified PEEK (PEEK/CaP-GS) by LBL exhibited antibacterial and osseointegration ability•PEEK/CaP-GS exhibited in vivo antibacterial and osseointegration ability for bone defect with infection treatment•PEEK/CaP-GS*6 obtained fro