Gradient Chitosan Hydrogels Modified with Graphene Derivatives and Hydroxyapatite: Physiochemical Properties and Initial Cytocompatibility Evaluation

Abstract

In this study, we investigated preparation of gradient chitosan-matrix hydrogels through a novel freezing–gelling–thawing method. The influence of three types of graphene family materials (GFM), i.e., graphene oxide (GO), reduced graphene oxide (rGO), and poly(ethylene glycol) grafted graphene oxide (GO-PEG), as well as hydroxyapatite (HAp) on the physicochemical and biological properties of the composite hydrogels was examined in view of their potential applicability as tissue engineering scaffolds. The substrates and the hydrogel samples were thoroughly characterized by X-ray photoelectron spectroscopy, X-ray diffractometry, infrared spectroscopy, digital and scanning electron microscopy, rheological and mechanical analysis, in vitro chemical stability and bioactivity assays, as well as initial cytocompatibility evaluation with human umbilical cord Wharton’s jelly mesenchymal stem cells (hUC-MSCs). We followed the green-chemistry approach and avoided toxic cross-linking agents, using instead specific interactions of our polymer matrix with tannic acid, non-toxic physical cross-linker, and graphene derivatives. It was shown that the most promising are the gradient hydrogels modified with GO-PEG and HAp.

The potential of nano graphene oxide and chlorhexidine composite membranes for use as a surface layer in functionally graded membranes for periodontal lesions

“…A faster weight loss profile was observed for CCG, followed by 3322, 3511, and CH. Rapid degradation of scaffolds within the first two weeks of analysis has been reported earlier as well [ 28 ]. With respect to CCG membranes, the presence of CHX might accelerate degradation by disrupting the enzymatic process.…”

“…The lower transparency of CCG could be due to the non-covalent physical adsorption of CH on both sides of the GO sheets [ 26 ]. HA has a proven record of triggering bone formation in in- vivo conditions [ 10 , 11 , 23 , 27 , 28 ]. Hence, it was added in different ratios to the membranes synthesized in this study.…”

The Functional and Application Possibilities of Starch/Chitosan Polymer Composites Modified by Graphene Oxide

“…These advantages make it possible to use graphene for stabilization and structure reinforcement of polymers that have certain limitations; i.e., natural polymers such as starch, chitosan, cellulose, alginates, hyaluronic acid, which, despite their many advantages, show weak barrier properties or poor mechanical properties. On the other hand, natural polymers, thanks to their attributes such as low production costs, biodegradability, renewability, lack of toxicity and high compatibility with various materials, can be good carriers of nanoparticles [ 5 , 35 , 36 , 37 , 38 , 39 , 40 , 41 ].…”

Graphene-Based Materials in Dental Applications: Antibacterial, Biocompatible, and Bone Regenerative Properties

“…In vivo studies also showed that osseointegration enhancement of the material was observed when implanted into rats [ 105 ]. In addition, other researchers added PEG to a chitosan/HAP-based scaffold that was GO modified and found that the addition of PEG in the scaffold may assist in increasing cell proliferation compared to scaffold that did not include PEG [ 130 ]. From these above studies, using graphene with HAP composites graphene has shown to exhibit good biocompatibility and increase cell attachment and proliferation in bone tissue engineering for dental and bone regenerative applications.…”