The construction of a self-assembled coating with chitosan-grafted reduced graphene oxide on porous calcium polyphosphate scaffolds for bone tissue engineering

Abstract

Bone regeneration in large bone defects remains one of the major challenges in orthopedic surgery. Calcium polyphosphate (CPP) scaffolds possess excellent biocompatibility and exhibits good bone ingrowth. However, the present CPP scaffolds lack enough osteoinductive activity to facilitate bone regeneration at bone defects that exceed the critical size threshold. To endow CPP scaffolds with improved osteoinductive activity for better bone regeneration, in this study, a self-assembled coating with chitosan-grafted reduced graphene oxide (CS-rGO) sheets was successfully constructed onto the surface of CPP scaffolds through strong electrostatic interaction and hydrogen bonds. Our results showed that the obtained CPP/CS-rGO composite scaffolds exhibited highly improved biomineralization and considerable antibacterial activity. More importantly, CPP/CS-rGO composite scaffolds could drive osteogenic differentiation of BMSCs and significantly up-regulate the expression of osteogenesis-related proteins in vitro. Meanwhile, the CS-rGO coating could inhibit aseptic loosening and improve interfacial osseointegration through stimulating BMSCs to secrete more OPG and lesser RANKL. Overall, the CS-rGO coating adjusts CPP scaffolds’ biological environment interface and endows CPP scaffolds with more bioactivity.

3D Molybdenum Disulfide Nanospheres Loaded with Metformin to Enhance SCPP Scaffolds for Bone Regeneration

“…The quantitative analysis result of ARS extracts (Figure e) indicated that the SCPP/MoS 2 -MET group had a stronger mineralization capacity compared with the other groups. This suggested SCPP/MoS 2 -MET possessed a better osteogenic potential under inflammatory conditions, both early (demonstrated by ALP staining) and late (demonstrated by ARS staining) stage . This could be attributed to the long-term release of metformin acting as an anti-inflammatory agent.…”

“…This suggested SCPP/MoS 2 -MET possessed a better osteogenic potential under inflammatory conditions, both early (demonstrated by ALP staining) and late (demonstrated by ARS staining) stage. 51 This could be attributed to the long-term release of metformin acting as an anti-inflammatory agent. Digital photos of ALP staining and ARS staining were displayed in Figure S9.…”

Zn-doped chitosan/alginate multilayer coatings on porous hydroxyapatite scaffold with osteogenic and antibacterial properties

“…They were deconvoluted into three principal peaks near 288.2, 286.6 and 284.8 eV, which were assigned O-C=O, C-O/C-N, and C-C bonds, respectively[ 35 , 36 ]. Figure 4D showed that the N 1s spectra and the peaks near 399.8 eV were attributed to amidogen groups (-NH 3+ )[ 37 ]. CHA-0 and CHA-H were selected because they were most likely to differ, and in fact all samples had similar C 1s and N 1s spectra.…”

Size-dependent molecular interaction of nontraditional 2D antibiotics with Staphylococcus aureus

“…Many applications are proposed for these carbon-based nanomaterials addressing different biomedical issues [6][7][8][9][10]. In recent years, many research groups have reported antibacterial performance for graphene, graphene oxide (GO), reduced GO, and other functionalized two and threedimensional nanomaterials based on the graphene family [11][12][13][14]. As a two-dimensional (2D) nanomaterial, GO possesses the significant properties of graphene such as a large specific surface area, and has a variety of oxygen-containing functional groups, making it a good candidate for an antibacterial material due to effective GO/bacteria interaction at the atomic scale.…”