Stimuli-responsive polymeric film based on hydrogen-bonded organic framework designing as a smart wound dressing

In this work, multifunctional polymeric film for wound dressing was prepared. The polymeric film was composed of polyvinyl alcohol, tannic acid, and a hydrogen-bonded organic framework (HOF) incorporating metronidazole. Metronidazole was encapsulated within the HOF for the first time, acting as a guest molecule and creating a new structure named MET.HOF. By leveraging the temperature and pH sensitivity of the hydrogen-bonded structures, metronidazole was released in a controlled manner at the wound site, adapting to the specific conditions of the wound. To investigate the controlled drug release, the responsiveness of the synthetic polymeric film was investigated at different temperatures (i.e., 37 °C and 40 °C) and pH levels (i.e., 5.5, 7.4, and 9) mimicking wound conditions. The results demonstrated that the polymeric film exhibited precise responsiveness to temperature (˃ 37 °C) and pH (alkaline pH ˃ acidic pH), enabling tailored drug release according to the specific wound type and severity. The average contact angle of the polymeric film was measured to be 67.5° ± 3.5. The degree of swelling calculated was 200% ± 50; additionally, the material exhibited antibacterial properties, with a minimal inhibitory concentration (MIC) of 1000 µg mL⁻¹ and a minimum bactericidal concentration (MBC) of 2000 µg mL⁻¹. These results highlighted the potential of this synthetic polymeric film as an advanced wound dressing material, capable of delivering drugs in a controlled manner based on the unique characteristics of the wound environment.

Graphical abstract