Modulating the elution of antibiotics from nanospongy titanium surfaces with a pH-sensitive coating

Abstract

Fraction of vancomycin eluted at 3 different pHs from bare nanospongy titanium (left) and from nanospongy titanium coated with uncross-linked (center, CH:PEG) and cross-linked (right, CH:PEG + GEN) chitosan–poly(ethylene glycol.

Smart stimuli-responsive strategies for titanium implant functionalization in bone regeneration and therapeutics

“…(1) Triggered antibacterial or anti-tumor drug release 25,97,98,[100][101][102][103][107][108][109][110][111][112][113] (1) Natural biomolecules (chitosan and silk fibroin) [97][98][99][100][101][102][103] (2) Conformation change of molecules (2) Surface potential changes promoting cell adhesion and osteogenesis [104][105][106] (2) Synthetic polymers (PMAA, DMMA and etc.) 25,104,105 (3) Cleavage of bonds/linkers (3) Inorganic molecules (MOFs, ZnO and etc.)…”

“…175,176 This phenomenon caused by pathological progress has been exploited by many researchers to design pH-responsive biomaterials with therapeutic and/or regenerative functions. 177,178 Accordingly, various pH-sensitive materials have been developed to construct titanium implants, including natural biomolecules (such as chitosan and silk fibroin), [97][98][99][100][101][102][103] synthetic polymers (such as PMAA), 25 inorganic molecules (such as metal-organic frameworks (MOFs) and ZnO) [106][107][108]179 and pH-sensitive bonds/linkers (such as Schiff base bonds, metal ions coordination bonds and boronic ester bonds). [108][109][110][111][112][113]180 Chitosan (Chi) is a natural cationic polysaccharide and has been widely used to fabricate biomaterials for bone regeneration, ascribed to its biocompatible and osteoinductive nature.…”

“…182 Therefore, many researches have been reported to fabricate Chi-based pHresponsive drug release systems on implant surfaces through various methods, including electrophoretic deposition and layer-by-layer (LBL) self-assembly. [98][99][100][101] For example, Ning et al 102 designed a pH-responsive Chi coating on titanium surface via electrophoretic deposition, which contained mesoporous silica nanoparticles (MSNs) loaded with copper peptide glycyl-L-histidyl-L-lysine-Cu 2+ (GHK-Cu). The pH-responsive release of Cu 2+ was validated, and in vitro experiments in this study suggested pretty cytocompatibility, outstanding antibacterial properties against E. coli and S. aureus.…”