Development and characterization of Pelargonium graveolens extract-loaded carrageenan/polyethylene glycol composite films for bioactive wound dressing applications

In this study, the bioactive wound dressing matrices were prepared by incorporating different concentrations of Pelargonium graveolens extract (PGE) into carrageenan/polyethylene glycol (CAR/PEG) composite films. HPLC analysis revealed the presence of several phenolic and flavonoid compounds in PGE, including naringenin (2624.06 μg/g), ferulic acid (1553.36 μg/g), quercetin (1217.04 μg/g), and gallic acid (1074.69 μg/g) as the major constituents. The free PGE showed considerable antioxidant activity with IC 50 values of 79.47 and 91.27 μg/mL in the DPPH and ABTS assays, respectively. The prepared films were coded as CAR/PEG, PGE-1@CAR/PEG, PGE-2@CAR/PEG, and PGE-4@CAR/PEG depending on the used concentration of PGE. Results of the SEM examination showed that the unloaded CAR/PEG film had a relatively smooth and uniform surface, whereas incorporation of PGE increased the surface roughness of the obtained films. Among the film formulations, PGE-4@CAR/PEG had the highest total phenolic and total flavonoid contents, 34.4 mg GAE/g and 14.7 mg QE/g, respectively. This formulation also displayed the highest antibacterial activity. The results of in vitro scratch assay displayed that the PGE-4@CAR/PEG significantly enhanced the fibroblast scratch closure after 48 h when compared to the control group, increasing from 63.50 ± 0.70% to 67.14 ± 0.64% (p = 0.0027). In conclusion, the results suggest that PGE-loaded CAR/PEG films, especially PGE-4@CAR/PEG, are promising initial bioactive wound-dressing candidates with antioxidant and antibacterial properties.