Rational integration of defense and repair synergy on PEEK osteoimplants via biomimetic peptide clicking strategy

Polyetheretherketone(PEEK)has been widely used as orthopedic and dental materials due to excellent mechanical and physicochemical tolerance.However,its biological inertness,poor osteoinduction,and weak antibacterial activity make the clinical applications in a dilemma.Inspired by the mussel adhesion mechanism,here we reported a biomimetic surface strategy for rational integration and optimization of anti-infectivity and osteo-inductivity onto PEEK surfaces using a mussel foot proteins(Mfps)-mimic peptide with clickable azido terminal.The peptide enables mussel-like adhesion on PEEK biomaterial surfaces,leaving azido groups for the further steps of biofunctionalizations.In this study,antimicrobial peptide(AMP)and osteogenic growth peptide(OGP)were bioorthogonally clicked on the azido-modified PEEK biomaterials to obtain a dual-effect of host defense and tissue repair.Since bioorthogonal clicking allows precise collocation between AMP and OGP through changing their feeding molar ratios,an optimal PEEK surface was finally obtained in this research,which could long-term inhibit bacterial growth,stabilize bone homeostasis and facilitate interfacial bone regeneration.In a word,this upgraded mussel surface strategy proposed in this study is promising for the surface bioengineering of inert medical implants,in particular,achieving rational integration of multiple biofunctions to match clinical requirements.

Dynamic Colloidal Photonic Crystal Hydrogels with Self-Recovery and Injectability

Simulation of self-recovery and diversity of natural photonic crystal(PC)structures remain great challenges for artificial PC materials.Motivated by the dynamic characteristics of PC nanostructures,here,we present a new strategy for the design of hydrogel-based artificial PC materials with reversible interactions in the periodic nanostructures.The dynamic PC hydrogels,derived from self-assembled microgel colloidal crystals,were tactfully constructed by reversible crosslinking of adjacent microgels in the ordered structure via phenylboronate covalent chemistry.As proof of concept,three types of dynamic colloidal PC hydrogels with different structural colors were prepared.All the hydrogels showed perfect self-healing ability against physical damage.Moreover,dynamic crosslinking within the microgel crystals enabled shear-thinning injection of the PC hydrogels through a syringe(indicating injectability or printability),followed by rapid recovery of the structural colors.In short,in addition to the great significance in biomimicry of self-healing function of natural PC materials,our work provides a facile strategy for the construction of diversified artificial PC materials for different applications such as chem-/biosensing,counterfeit prevention,optical display,and energy conversion.