Adjustable dielectric and bioactivity characteristics of chitosan-based composites via crosslinking approach and incorporation of graphene

• Published in: International journal of biological macromolecules 2024-06, Vol.270 (Pt 1), p.132125-132125, Article 132125
• Main Authors: Cicek Ozkan, Betul, Guner, Melek
• Format: Article
• Language: English
• Subjects: Bioactivity; Biocompatible Materials - chemistry; Chitosan; Chitosan - chemistry; Cross-Linking Reagents - chemistry; Dielectric permittivity; Graphene; Graphite - chemistry; Polymer nanocomposites; SBF; Spectroscopy, Fourier Transform Infrared; X-Ray Diffraction
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2024.132125

This study explores the structural, electrical, dielectric, and bioactivity properties of chitosan (CS) composites incorporating graphene (G) nanoparticles. Characterization techniques, including Field Emission Scanning Electron Microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), dielectric spectroscopy, and in vitro testing in SBF, were employed to investigate the effects of G content and crosslinking. The XPS peak at 289.89 eV for CS-G10 indicates CC and CH bonds, suggesting significant interactions between chitosan's hydroxyl groups and graphene's carbon atoms, ensuring structural homogeneity. Dielectric constant (ε’) gradually increased with G loading (0 %, 1 %, 5 %, and 10 %) for uncrosslinked composites, reaching 17.94, 18.92, 28.28, and 41.1, respectively. Crosslinked composites exhibited reduced ε’ values (15.71, 15.42, 14.14, and 27.03) compared to non-crosslinked ones, with marginal increases post-percolation threshold (5 wt% G filling). XRD analysis revealed shifts in characteristic peaks of CS after SBF treatment, with new peaks at 28.9° and 48.5° indicating hydroxyapatite presence, confirming composite bioactivity. CS-G10/GA showed the highest bioactivity, suggesting promise for biomedical applications.