Richárd Kajtár

Background: Cyclodextrin (CD) polymers have attracted increasing attention due to their favourable drug delivery properties and broad pharmaceutical applicability. While the bioavailability and biological behaviour of native cyclodextrins have been extensively investigated, considerably less information is available regarding modified cyclodextrin polymers. Therefore, the present study aimed to investigate the permeation and cellular uptake of an epichlorohydrin-crosslinked β-cyclodextrin polymer using multiple in vitro and ex vivo models. Methods: Fluorescently labelled β-cyclodextrin polymers were applied in all experiments. Membrane permeation studies were performed using an in-line diffusion cell system with membranes of different pore sizes. In vitro transport and cellular uptake were investigated on HaCaT, Caco-2, and TR146 cell monolayers, while ex vivo permeation studies were carried out using skin, buccal, and intestinal tissues. Results: The results demonstrated a strong size-dependent transport behaviour across synthetic membranes. Cell monolayer studies revealed cell-line-dependent differences in polymer intracellular distribution. Lysosomal accumulation was observed in HaCaT and Caco-2 cells, whereas no intracellular accumulation was detected in TR146 cells. These findings suggest differences in polymer permeation among the investigated cell models. Ex vivo studies demonstrated the tissue permeation of cyclodextrin polymers, with marked accumulation within skin layers, indicating predominant dermal retention. Furthermore, strong correlations were identified between the in vitro and ex vivo skin and intestinal models. Conclusions: Overall, the findings demonstrate that β-cyclodextrin polymers exhibit complex, barrier-dependent transport behaviour across different biological models. The observed differences in permeation and intracellular localization suggest that multiple transport processes may contribute to their biological interactions, which provide a foundation for future studies aimed at elucidating the molecular mechanisms governing polymer uptake and permeation.

Background: Artemisia annua L. is a medicinal plant with documented antimicrobial, antioxidant, and anti-inflammatory properties. Although widely studied for internal therapeutic applications, its topical use—especially in hydrogel-based systems—has not been thoroughly investigated. The aim of this study was to develop sodium alginate hydrogels containing Artemisia annua extract, supplemented with hyaluronic acid and dexpanthenol, and to evaluate their physicochemical characteristics as well as their biological activities in vitro and in vivo. Methods: Select bioactive constituents of the Artemisia annua extract were quantified using liquid chromatography coupled with electrospray ionization mass spectrometry (LC-ESI-MS). Hydrogels were prepared by cross-linking sodium alginate with a calcium carbonate–glucono-delta-lactone system and were formulated with or without hyaluronic acid and dexpanthenol. Physicochemical evaluations included measurements of moisture content, water-retention capacity, gelation time, and pH. The hydrogel microstructure was examined by scanning electron microscopy (SEM). Antioxidant activity was assessed using three methods: the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, the ferric reducing antioxidant power (FRAP) assay, and the cupric reducing antioxidant capacity (CUPRAC) assay. Biocompatibility and regenerative effects were analyzed using cell viability assays and an in vitro scratch wound model on human keratinocyte cells. In vivo wound-healing efficacy was examined in rats with full-thickness skin excisions. Results: The extract contained high levels of methylated flavonoids and sesquiterpenes characteristic of Artemisia annua. Hydrogels supplemented with hyaluronic acid and dexpanthenol exhibited improved hydration stability and higher porosity. All formulations demonstrated measurable antioxidant activity, and those containing hyaluronic acid showed the strongest effects. The preparations were biocompatible and enhanced keratinocyte migration in vitro, with the combined hyaluronic acid–dexpanthenol formulation promoting the fastest wound closure. In vivo, Artemisia annua hydrogels accelerated wound healing by two to three days compared with untreated wounds. Conclusions: These results confirm the promise of Artemisia annua hydrogels for topical wound care and highlight the beneficial contributions of hyaluronic acid and dexpanthenol to their structural and therapeutic performance.