The aim of this paper was to prepare, by the freeze-drying method, ionically crosslinked chitosan membranes with different contents of pentasodium tripolyphosphate (TPP) and loaded with 1,4-naphthoquinone (NQ14) drug, in order to evaluate how the physical crosslinking affects NQ14 release from chitosan membranes for cancer therapy application. The membranes were characterized by Fourier transform infrared spectroscopy (FTIR), wide-angle X-ray diffraction (WAXD), scanning electron microscopy (SEM), swelling degree, and through in vitro drug release and cytotoxicity studies. According to the results, the molecular structure, porosity and hydrophilicity of the chitosan membranes were affected by TPP concentration and, consequently, the NQ14 drug release behavior from the membranes was also affected. The release of NQ14 from crosslinked chitosan membranes decreased when the cross-linker TPP quantity increased. Thus, depending on the TPP amount, the crosslinked chitosan membranes would be a potential delivery system to control the release of NQ14 for cancer therapy application. Lastly, the inhibitory potential of chitosan membranes ionically crosslinked with TPP and loaded with NQ14 against the B16F10 melanoma cell line was confirmed through in vitro cytotoxicity studies assessed via MTT assay. The anti-proliferative effect of prepared membranes was directly related to the amount of cross-linker and among all membranes prepared, such that one crosslinked with 0.3% of TPP may become a potential delivery system for releasing NQ14 drug for cancer therapy.

Nowadays, the need to reduce the dependence on fuel products and to achieve a sustainable development is of special importance due to environmental concerns. Therefore, new alternatives must be sought. In this work, extruded fibers from poly (lactic acid) (PLA) and poly (butylene adipate-co-terephthalate) (PBAT) added with cinnamon essential oil (CEO) were prepared and characterized, and the hydrolytic degradation was assessed. A two-phase system was observed with spherical particles of PBAT embedded in the PLA matrix. The thermal analysis showed partial miscibility between PLA and PBAT. Mechanically, Young’s modulus decreased and the elongation at break increased with the incorporation of PBAT and CEO into the blends. The variation in weight loss for the fibers was below 5% during the period of hydrolytic degradation studied with the most important changes at 37 °C and pH 8.50. From microscopy, the formation of cracks in the fiber surface was evidenced, especially for PLA fibers in alkaline medium at 37 °C. This study shows the importance of the variables that influence the performance of polyester-cinnamon essential oil-based fibers in agro-industrial applications for horticultural product preservation.

Biofabrication is an incipient and fast-growing field of research that continues to develop groundbreaking innovations. Considerable progress has also been made in additive manufacturing technologies, which are used for the production of complex geometry using biomaterials, such as scaffolds and, most recently, bioink-based structures. Some of the topics related to these new breakthroughs in tissue engineering and bioprinting will be discussed. Additionally, the obtained experimental results in this work contribute to the recent advances in such sciences. Formulations of sodium alginate (NaAlg)/Poly(N-Isopropylacrylamide) (PNIPAm)/ZnSO₄-based smart bioinks were developed and characterized. The lower critical solution temperature (LCST), viscosity, and thermal stability were determined through UV-Visible spectroscopy, a rheological analysis and a thermogravimetric analysis (TGA), respectively. Furthermore, an injectability test was performed in order to assess the influence of the extrusion process in the morphology of the bioinks like scaffolds (after lyophilization) using scanning electron microscopy SEM. According to the obtained results, the scaffolds presented a structure composed of interconnected pore systems, which were affected by the presence of the Zn²⁺ ion, and the extrusion process. The biocompatibility of the gels was tested through a hemolysis assay using erythrocytes and the obtained results indicate that have not cytotoxic effects. For all these reasons these formulations are candidates for the obtention of intelligent bioinks applicable for bioprinting and tissue engineering.