The influence of the pectin structure on the properties of hydrogel dressings doped with octenidine-containing antiseptic.

This article presents a method for producing hydrogel dressings using high methylated pectin from apples or citrus, doped with the antiseptic agent, octenidine dihydrochloride. Octenidine was incorporated in-situ during the polymer crosslinking. The pectins were characterized by their varying molecular weight characteristics, monosaccharide composition, and degree of esterification (DE). The study assessed the feasibility of producing biologically active hydrogels with pectin and delved into how the polymer's characteristics affect the properties of the resulting dressings. The structure evaluation of hydrogel materials showed interactions between individual components of the system and their dependence on the type of used pectin. Both the antimicrobial properties and cytotoxicity of the dressings were evaluated. The results suggest that the primary determinants of the functional attributes of the hydrogels are the molecular weight characteristics and the DE of the pectin. As these values rise, there is an increase in polymer-polymer interactions, overshadowing polymer-additive interactions. This intensification strengthens the mechanical and thermal stability of the hydrogels and enhances the release of active components into the surrounding environment. Biological evaluations demonstrated the ability of octenidine to be released from the dressings and effectively inhibit the growth of microbial pathogens.

Mechanical and Antimicrobial Properties of the Graphene-Polyamide 6 Composite.

This paper presents the synthesis and characterization of graphene-polymer composites, focusing on their mechanical and antibacterial properties. Graphene flakes were obtained via an electrochemical method and integrated into polyamide 6 (PA6) matrices using melt intercalation. Various characterization techniques confirmed the quality of the graphene flakes, including X-ray diffraction (XRD), Raman spectroscopy, and infrared (IR) spectroscopy, as well as scanning and transmission electron microscopy (SEM and TEM) imaging. Mechanical tests showed an increase in the elastic modulus with graphene incorporation, while the impact strength decreased. The SEM analysis highlighted the dispersion of the graphene flakes within the composites and their impact on fracture behavior. Antimicrobial tests demonstrated significant antibacterial properties of the composites, attributed to both oxidative stress and mechanical damage induced by the graphene flakes. The results suggest promising applications for graphene-polymer composites in advanced antimicrobial materials.