Two-dimensional superlattice films of gold nanoparticle-polystyrene composites: a bioactive platform for bone homeostasis maintenance

Osseo-integration between the implant and bone is a crucial factor to create a strong, durable bond that allows the implant to function effectively. However, regular implant surface with poor osseo-integration ability may cause aseptic loosening, resulting in the failure of implants. Herein, a serial of macroscopic one-particle thick superlattice films generated by self-assembly of diverse size of gold nanoparticles (GNPs) were termed as SFGs and were considered as bioactive implant coatings for enhancing osseo-integration. A hydroquinone-assisted seed method is established to fabricate homogenous GNPs with controllable sizes (20, 60, and 90 nm), which were further employed as building blocks to generate macroscopic one-particle thick superlattice films of GNPs (SFGs-20, SFGs-60, and SFGs-90) with the assistance of ploystryrene. The SFGs present a size-dependent performance on bone homeostasis, where SFGs-90 demonstrated the most pronounced facilitation of osteogenic differentiation of osteoblasts as well as deactivation of osteoclasts compared with SFGs-20 and SFGs-60. Considering the universal applicability of SFGs for depositing on various substrates, these SFGs with enhanced osseo-integration capabilities could serve as a bioactive platform for surface modification of orthopedic implants, effectively addressing the issue of aseptic loosening.Graphical abstractTwo-dimensional superlattice films of gold nanoparticle-polystyrene composites exhibit enhanced osteogenic-stimulation and osteoclastic-inhibition effects for regulating bone homeostasis maintenance.