In this study, films of O-carboxymethyl chitosan with Mimosa tenuiflora extract were manufactured, characterized, and evaluated. In this work, both the synthesis of O-carboxymethyl chitosan and the extraction of the active ingredient of Mimosa tenuiflora extract from the cortex are described. First, the extract of Mimosa tenuiflora in water was obtained by precipitation with ethanol, filtering, and concentrating. Subsequently, a study was conducted of scratch wound healing to determine the optimal concentration of extract to be used in the manufacture of films. The produced O-carboxymethyl chitosan films and the Mimosa tenuiflora extract were mixed, and their chemical composition, tensile properties, and wettability were characterized by Fourier-transform infrared spectroscopy, mechanical tests, and contact angle measurement. The antimicrobial properties of the films were tested by turbidimetry using two types of bacteria. In addition, a study of the enzymatic degradation of the films with the enzyme lysozyme was performed. Finally, in vitro studies to assess the biocompatibility and cytotoxicity of films with fibroblastic cells were carried out as well as the kinetic analysis of healing in mice. It was found that the addition of Mimosa tenuiflora extract in the polymer matrix of the films made with O-carboxymethyl chitosan improves the proliferation of fibroblast and accelerates wound healing, thus providing a novel biomaterial for skin regeneration.

El presente artículo es una amplia revisión bibliográfica de algunos de los polímeros naturales más utilizados en la fabricación de apósitos para curación de heridas cutáneas y regeneración de piel en los últimos años. Asimismo, se presenta un análisis descriptivo de los polímeros de origen natural más estudiados en la ingeniería de tejidos, remarcando sus propiedades físicas, químicas y biológicas. Encontrando que las investigaciones más recientes se han centrado en la exploración de apósitos a partir de biopolímeros como una alternativa a los materiales sintéticos derivados del petróleo, debido a las propiedades que poseen, como una mayor biodegradabilidad, biocompatibilidad y sostenibilidad por ser obtenidos naturalmente. Sin embargo, aún no existe un apósito ideal que pueda ser aplicado de manera eficiente en todos los tipos de heridas; por lo que los investigadores se han enfocado en el desarrollo y la optimización de apósitos que satisfagan la mayoría de las necesidades para una etapa en particular de la herida.

The dressings are materials that can improve the wound-healing process in patients with medical issues. Polymeric films are frequently used as dressings with multiple biological properties. Chitosan and gelatin are the most used polymers in tissue regeneration processes. There are usually several configurations of films for dressings, among which the composite (mixture of two or more materials) and layered ones stand out (layers). This study analyzed the antibacterial, degradable, and biocompatible properties of chitosan and gelatin films in 2 configurations, composite and bilayer, composite. In addition, a silver coating was added to enhance the antibacterial properties of both configurations. After the study, it was found that the bilayer films have a higher antibacterial activity than the composite films, having inhibition halos between 23% and 78% in Gram-negative bacteria. In addition, the bilayer films increased the fibroblast cell proliferation process, reaching up to 192% cell viability after 48 h of incubation. On the other hand, composite films have greater stability since they are thicker, with 276 µm, 243.8 µm, and 239 µm compared to 236 µm, 233 µm, and 219 µm thick for bilayer films; and a low degradation rate compared to bilayer films.

<abstract> <p>Nowadays, the treatment for bone damage remains a significant challenge. As a result, the development of bioactive three-dimensional scaffolds for bone regeneration has become a key area of study within tissue engineering. This research is focused on the evaluation of the properties of Chitosan (Ch)/Polycaprolactone (PCL) scaffolds with the <italic>Mytilus californiensis</italic> protein by Thermally Induced Phase Separation (TIPS). This study used the extrapalleal fluid protein from <italic>Mytilus californiensis</italic> because it increases biological processes that support bone regeneration. Two methodologies were used for the scaffolds functionalization: (I) an immersion process in a solution with the protein and (II) the protein direct addition during the scaffold synthesis. The scaffolds were analyzed by Fourier Transformed Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), and Mechanical Compression test to determine the composition, morphology, and mechanical properties of each material. <italic>In vitro</italic> analysis of biodegradation, bioactivity, and biocompatibility were also performed. The scaffolds with the protein added directly presented superior properties in the tests of bioactivity and cellular proliferation, making these composites attractive for the area of bone regeneration.</p> </abstract>