Systematically engineered graphene sheets with electrostatic Au-reinforcement to strengthen 2D nanofibrous scaffolds for improved bone regeneration

Abstract

Here, we report the polycaprolactone (PCL) based 2D nanofibrous scaffold with minimal loading (0.0005-0.002 wt%) of Au-reinforced graphene (RG) sheets for improved bone tissue regeneration. The microsized graphene oxide (GO) sheets (829 nm) were tailored strategically to 282 nm-sized monodispersed nanosheets for uniform electrostatic attachment of gold nanoparticles (GNPs). The GNPs-GO sheets were reduced to GNPs-RG sheets using a visible-light-induced chemical-free green method where the oxygen functional groups of GO have not been removed completely to enhance the functionality of GNPs-RG for bone tissue regeneration. The monodispersibility of GNPs-RG sheets helped to prepare PCL-based nanofibrous scaffolds with uniformly distributed GNPs-RG (0.002 wt%) with higher electrical conductivity (>3.5 times) and greater mechanical strength (>4.5 times). The electrostatic field simulation studies with COMSOL suggested that there was a uniform distribution of the electric field. The GNPs-RG addition creates an apt adhesion site due to their multifunctional and conductive properties for PCL@GNPs-RG nanofibrous scaffold which resulted in enhanced cell adhesion and proliferation of MC3T3-E1 cells. The PCL@GNPs-RG nanofibrous scaffold showed higher alkaline phosphatase activity and improved calcium mineralization after 21 d of incubation. The results indicated that the PCL@GNPs-RG scaffold has a promising capacity and potential for bone tissue regeneration.

Nanogap-containing thermo-plasmonic nano-heaters for amplified photo-triggered tumor ablation at low laser power density

“…34 The low Miller index faces such as (220), (200), and (111), which are present in GNSs, are considered more stable than others because they possess denser atomic packing. 35 The HRTEM image (Fig. S4A, ESI †) of single particles confirmed the Pt coating on GNSs without any nanogaps, and similarly, Fig.…”