Mechanical and rheological properties of Pluronic F127 based-hydrogels loaded with chitosan grafted with hyaluronic acid and propolis, focused to atopic dermatitis treatment

Hydrogels for biomedical applications have been widely studied once they are able to enhance the wound- healing process, as well as facilitate the controlled release and loading of drugs. In this context, Pluronic F127 (PF127) has a major role as it was shown to have exceptional versatility, once it holds unique gelation properties, as it is thermoreversible and is liquid in lower temperatures, and changes to gel in higher temperatures. Moreover, the gelation behavior of PF127 is influenced by its concentration and can be further modulated by incorporating different compounds, including drugs. In this study, the mechanical and rheological properties of Pluronic F127-based hydrogels were evaluated to be further used as a treatment for atopic dermatitis (AD). To this purpose, it was conducted Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), rheology, adhesivity, cohesion, and compression assays, allowed us to understand the effects of different concentrations of PF127 and how it behaves after incorporating compounds (chitosan grafted with hyaluronic acid (Ch/HA), and propolis), aiming to identify optimal combinations for the hydrogel formulation. To provide a reliable formulation, the study first selected the most suitable concentration of PF127, in the sequence it incorporated Ch/HA and lastly, propolis was added. The findings have provided valuable insights regarding the selection of the formulations, correlating the mechanical, rheological, and morphological data. It is expected that the formulation achieved is able to further be applied to the wounded skin, providing a low-cost and effective alternative to the treatment of AD.