Chitosan: Structural and Chemical Modification, Properties, and Application

Chitosan is a polymer of natural origins that possesses many favourable properties [...].

The antioxidant, anti-angiogenic, and anticancer impact of chitosan-coated herniarin-graphene oxide nanoparticles (CHG-NPs)

Background

Herniarin, a simple coumarin found in chamomile leaf rosettes is known as the oxidative stress protector. In the current study, herniarin was captured into Graphene oxide nanoparticles and coated with chitosan poly-cationic polymer to be used as a novel bio-compatible nano-drug delivery system and investigate its antioxidant, anti-angiogenic and anti-cancer impacts on human lung A549 cancer cells.

Method

The Chitosan-coated Herniarin-Graphene oxide nanoparticles (CHG-NPs) were designed, produced, and characterized utilizing DLS, FESEM, FTIR, and Zeta-potential analysis. The CHG-NPs' antioxidant activity was analyzed by conducting ABTS and DPPH antioxidant assays. The CHG-NPs' anti-angiogenic activity was analyzed by CAM assay and verified by measuring VEGF and VEGFR gene expression levels following their increased treatment doses by applying Q-PCR technique. Finally, the CHG-NPs' cytotoxicity was studied in the human lung A549 cancer cells.

Result

The stable (+27.11 mV) 213.6-nm CHG-NPs significantly inhibited the ABTS/DPPH free radicals and exhibited antioxidant activity. The suppressed angiogenesis process in the CAM vessels was observed by detecting the decreased length/number of the vessels. Moreover, the down-regulated VEGF and VEGFR gene expression of the CAM blood vessels following the increased CHG-NPs treatment doses verified the nanoparticles' anti-angiogenic potential. Finally, the CHG-NPs significantly exhibited a selective cytotoxic impact on human A549 cancer cells compared with the normal HFF cell line.

Conclusion

The selective cytotoxicity, strong antioxidant activity, and significant anti-angiogenic property of the nano-scaled produced CHG-NPs make it an appropriate anticancer nano-drug delivery system. Therefore, the CHG-NPs have the potential to be used as a selective anti-lung cancer compound.

Functional Three-Dimensional Graphene/Polymer Composites

Integration of graphene with polymers to construct three-dimensional porous graphene/polymer composites (3DGPCs) has attracted considerable attention in the past few years for both fundamental studies and diverse technological applications. With the broad diversity in molecular structures of graphene and polymers via rich chemical routes, a number of 3DGPCs have been developed with unique structural, electrical, and mechanical properties, chemical tenability, and attractive functions, which greatly expands the research horizon of graphene-based composites. In particular, the properties and functions of the 3DGPCs can be readily tuned by precisely controlling the hierarchical porosity in the 3D graphene architecture as well as the intricate synergistic interactions between graphene and polymers. In this paper, we review the recent progress in 3DGPCs, including their synthetic strategies and potential applications in environmental protection, energy storage, sensors, and conducting composites. Lastly, we will conclude with a brief perspective on the challenges and future opportunities.

Recent Advances in Nanocomposite Materials of Graphene Derivatives with Polysaccharides

This review article presents the recent advances in syntheses and applications of nanocomposites consisting of graphene derivatives with various polysaccharides. Graphene has recently attracted much interest in the materials field due to its unique 2D structure and outstanding properties. To follow, the physical and mechanical properties of graphene are then introduced. However it was observed that the synthesis of graphene-based nanocomposites had become one of the most important research frontiers in the application of graphene. Therefore, this review also summarizes the recent advances in the synthesis of graphene nanocomposites with polysaccharides, which are abundant in nature and are easily synthesized bio-based polymers. Polysaccharides can be classified in various ways such as cellulose, chitosan, starch, and alginates, each group with unique and different properties. Alginates are considered to be ideal for the preparation of nanocomposites with graphene derivatives due to their environmental-friendly potential. The characteristics of such nanocomposites are discussed here and are compared with regard to their mechanical properties and their various applications.