Polyvinylic Gels as Promising Antimicrobial Wound Dressings: Development, Characterization, and In Vitro Evaluation

This thesis addresses the challenge of treating chronic wounds in the face of growing antibiotic resistance, emphasizing the need for innovative dressing technologies. Chronic wounds, defined as those not healing within 6-8 weeks and often stalled in the inflammatory phase, are influenced by various factors and undergo stages of hemostasis, inflammation, proliferation, and maturation. It discusses different chronic wounds, such as arterial, venous, pressure, and diabetic foot ulcers, and it introduces the TIME principle as the gold standard for chronic wound treatment. The study highlights the issue of antibiotic resistance and the exploration of silver-based and other antimicrobial treatments. Moreover, it delves into tissue engineering and regenerative medicine, aiming to create functional tissue substitutes. In particular, in this thesis, antimicrobial dressings are developed in hydrogel, known for its ability to absorb and retain fluids while maintaining a solid form. Two synthetic polymers, Polyvinyl alcohol (PVA) and Polyvinylpyrrolidone (PVP) are highlighted for their stability and biocompatibility. The research conducted at Tiss' You S.R.L. Regenerative Company aimed to create the 'Sterify Patch,' a 3D patch with antibacterial properties derived from the patented composition of 'Sterify Gel'. A comprehensive overview of analytical methods is provided, including rheological techniques, infrared spectroscopy, and microbial testing aiming to optimize the hydrogel's polymeric composition for effective wound healing. Initial experiments led to various formulations, with a focus on adjusting PVA and PVP percentages to achieve the desired antibacterial efficacy and 3D structure. The formulations that have proven to be most suitable are those with at least 15% PVA. Rheological analysis indicated viscosity increase linked to PVA concentration and sterilization. FT-IR analysis post-sterilization revealed new chemical bonds, suggesting a potential polymeric or crosslinking nature and the microbial tests showed promising antibacterial effectiveness. In conclusion, the thesis addresses the global health challenge of managing chronic wounds by developing an innovative three-dimensional hydrogel patch, the "Sterify Patch," designed to treat challenging wounds by promoting absorption and preventing contamination, particularly in the context of antibiotic resistance.