The requisite to obtain reduced graphene oxide as an individual sheet and to maintain it in the reduced form introduces a new way of manipulative nanocomposite systems (e.g., semiconductor or metal nanoparticle and graphene composite). Herein, we developed a simple suitable UV-.assisted photocatalytic reduction method to prepare the most viable nanocomposite ZnO/RGO. Graphene oxide undergoes reduction reaction in ethanol- water system as it accepts electrons from UV irradiated semiconductor (ZnO), and subsequently characterized using different standard techniques. The presence of graphene in the composites were confirmed by X-ray diffraction (XRD), Raman, FTIR, SEM, TEM, and X-ray photoelectron spectroscopy (XPS) analysis. The highly efficient ZnO/RGO nanocomposite exhibited enhanced photocatalytic degradation performance for the degradation of methylene blue, with a maximum removal rate of (∼80%) as compared with pure ZnO nanoparticles (∼68%). This effective increase in degradation were caused by the prevention of electron–hole pair recombination in ZnO with the introduction of RGO. These findings suggest that the synthesized ZnO/RGO nanocomposite via photocatalytic approach not only offers UV-assisted reduction technique, but also open up a new way to obtain photoactive graphene-semiconductors, which could be effectively used in various application.

Wound healing, particularly for difficult-to-treat wounds, presents a serious threat and may lead to complications. Currently available dressings lack mucoadhesion, safety, efficacy, and, most importantly, patient compliance. Herein, we developed a unique, simple, and inexpensive injectable chitosan-methoxy polyethylene glycol (chitosan-mPEG) hybrid hydrogel with tunable physicochemical and mechanical properties for wound healing. The detailed physicochemical and rheological characterization of the chitosan-mPEG hydrogel has revealed chemical interaction between available -NH₂ groups of chitosan and -COOH groups of mPEG acid, which, to our perspective, enhanced the mechanical and wound healing properties of hybrid chitosan and mPEG hydrogel compared to solo chitosan or PEG hydrogel. By introducing mPEG, the wound healing ability of hydrogel is synergistically improved due to its antibacterial feature, together with chitosan's innate role in hemostasis and wound closure. The detailed hemostasis and wound closure potential of the chitosan-mPEG hydrogel were investigated in a rat model, which confirmed a significant acceleration in wound healing and ultimately wound closure. In conclusion, the developed chitosan-mPEG hydrogel met all the required specifications and could be developed as a promising material for hemostasis, especially wound management, and as an excellent candidate for wound healing application.

The present study analyzes the capacity of collagen (coll)/sulfated glycosaminoglycan (sGAG)-based surface coatings containing bioactive glass nanoparticles (BGN) in promoting the osteogenic differentiation of human mesenchymal stroma cells (hMSC). Physicochemical characteristics of these coatings and their effects on proliferation and osteogenic differentiation of hMSC were investigated. BGN were stably incorporated into the artificial extracellular matrices (aECM). Oscillatory rheology showed predominantly elastic, gel-like properties of the coatings. The complex viscosity increased depending on the GAG component and was further elevated by adding BGN. BGN-containing aECM showed a release of silicon ions as well as an uptake of calcium ions. hMSC were able to proliferate on coll and coll/sGAG coatings, while cellular growth was delayed on aECM containing BGN. However, a stimulating effect of BGN on ALP activity and calcium deposition was shown. Furthermore, a synergistic effect of sGAG and BGN was found for some donors. Our findings demonstrated the promising potential of aECM and BGN combinations in promoting bone regeneration. Still, future work is required to further optimize the BGN/aECM combination for increasing its combined osteogenic effect.

Injectable gelatine-based hydrogels are valuable tools for drug and cell delivery due to their extracellular matrix-like properties that can be adjusted by the degree of cross-linking. We have established anhydride-containing oligomers for the cross-linking of gelatine via anhydride–amine-conjugation. So far, this conversion required conditions not compatible with cell encapsulation or in vivo injection. In order to overcome this limitation, we developed an array of quarter-oligomers varying in comonomer composition and contents of reactive anhydride units reactive towards amine groups under physiological conditions. The oligomers were of low molecular weight (M_n < 5 kDa) with a high degree of chemically intact anhydrides. Chemical comonomer composition was determined by ¹H-NMR. Dissolutions experiments confirmed improved hydrophilicity of the synthesized oligomers over our established compositions. Injectable formulations are described utilizing cytocompatible concentrations of constituent materials and proton-scavenging base. Degree of cross-linking and stiffness of injectable hydrogels were controlled by composition. The gels hold promise as injectable drug or cell carrier and as bioink.

Liposomes are promising drug carriers already used in clinical practice, but feasible methods for surface modifications are needed to enhance the application spectrum. This work describes the establishment of the first representative of amphiphilic functionalized oligomers as universal tool for the tuning of liposome characteristics based on a flexible building block strategy. The oligomer binds to liposomes composed of different lipids and modifies the surface characteristics. The charge of neutrally and even negatively charged liposomes is switched to a positive surface charge by grafting liposomes with the novel oligomer to create hybrid vesicles while integrity and structure of liposomes is not affected. The role of the alkyl chain anchors of the oligomer as driving force for formation of hybrid vesicles is demonstrated. The oligomer modification of liposomes is utilized to enhance the biological behavior of the vesicles demonstrated by an enhanced uptake in fibroblasts.