Ana Luiza de Sá Elias

Chronic wounds remain a major clinical challenge due to prolonged inflammation, infection, and delayed tissue regeneration. This study developed and characterized porous scaffolds based on chitosan, collagen, and ethanolic extract of Jatropha mollissima aimed at wound dressing applications. Scaffolds were prepared by lyophilization using different chitosan/collagen ratios, with and without plant extract incorporation. Physicochemical, morphological, and biological properties were evaluated by FTIR, optical microscopy, SEM, swelling, enzymatic biodegradation, and in vitro cytotoxicity assays. The results demonstrated good interaction between chitosan and collagen, the presence of porous and interconnected structures, swelling indices above 740%, controlled biodegradation, and absence of cytotoxic effects. The incorporation of Jatropha mollissima extract did not compromise scaffold stability or absorbency. These findings suggest that the developed scaffolds possess characteristics of interest for wound dressing applications. However, additional studies involving quantitative porosity measurements, wettability, and mechanical characterization are required to further validate their potential for difficult-to-heal wound treatment.

Varicose ulcers represent a severe manifestation of chronic venous insufficiency and remain a major public health challenge. In this study, chitosan-based dressings incorporating Jatropha mollissima extract (1-5% m/m) were developed via lyophilization to enhance healing performance. The membranes exhibited a predominantly fibrous morphology with high swelling capacity, approximately 1600% for pure chitosan, with a progressive reduction upon extract incorporation, indicating a decrease in hydrophilicity and increase in network density. Fourier transform infrared spectroscopy (FTIR) analysis revealed intensified bands associated with O–H and N–H groups, suggesting hydrogen bonding interactions between chitosan and phenolic compounds of the extract. Thermogravimetric analysis showed improved thermal stability, with reduced mass loss in extract-loaded membranes (ca. 50-60%) compared to pure chitosan. Biodegradation assays demonstrated a decrease in mass loss from 73.43 (M) to 65.00% (MJ5) after 21 days in phosphate salt (PBS), indicating enhanced structural stability. All samples exhibited no cytotoxicity toward L929 fibroblasts. These results demonstrate that the incorporation of J. mollissima modulates physicochemical properties through intermolecular interactions, leading to reduced swelling, controlled degradation, and improved stability. The study highlights the novelty of combining chitosan with a Caatinga-derived bioactive extract to produce multifunctional membranes with tunable physicochemical and biological properties, although further studies are required to confirm their suitability for biomedical applications.