Abstract Electrospinning method is widely used to develop biomaterials useful in regenerative medicine. The addition of bioactive compounds to a polymeric matrix provides properties that promote its use in biomedical applications. In this work poly(lactic acid) (PLA) electrospun (ES) fibers loaded with Rumex hymenosepalus extract were prepared and characterized with the aim of obtained a novelty material for potential wound dressings applications. ES PLA fibers were obtained using parameter variations and fibers obtained with a flow rate of 0.6 mL/h and voltage of 15 kV using a rotating drum were selected to continue the study. The fibers morphology was analyzed with scanning electron microscopy and their diameters were measured using ImageJ software. An alkaline hydrolysis was performed to improve the interaction sites of the ES fibers and R. hymenosepalus extract. FTIR-ATR study was performed to evaluate the behavior of the PLA and PLA hydrolyzed (PLA/H) fibers and its interaction with the extract. Antioxidant release study was carried out using UV-vis spectroscopy and with this evaluation it was determined that the alkaline hydrolysis helped to control the R. hymenosepalus release rate. These results show that obtained PLA-R. hymenosepalus fibers have potential use in antioxidant release applications like wound dressings.

Resumen El método de electrohilado es ampliamente utilizado para desarrollar biomateriales útiles en medicina regenerativa. La adición de compuestos bioactivos a matrices poliméricas les confiere propiedades que fomentan su uso en aplicaciones biomédicas. En este trabajo se prepararon y caracterizaron fibras electrohiladas de Poli(ácido láctico) (PLA) adicionadas con extracto de Rumex hymenosepalus con el objetivo de obtener un material novedoso con uso potencial como apósitos para heridas. Se obtuvieron fibras utilizando distintos parámetros y se seleccionaron las fibras obtenidas utilizando un rotor con velocidad de flujo de 0.6 mL/h y 15 kV de voltaje para continuar el estudio. La morfología de las fibras se examinó por microscopia electrónica de barrido y se determinaron los diámetros promedio. Se realizó una hidrólisis alcalina para mejorar la interacción de las fibras electrohiladas y el extracto de R. hymenosepalus. El estudio FTIR-ATR permitió evaluar la interacción de las fibras de PLA y PLA hidrolizado con el extracto de R. hymenosepalus. Los resultados del estudio de liberación por espectroscopia UV-vis mostraron que la hidrólisis alcalina ayuda a controlar la velocidad liberación del R. hymenosepalus. Los resultados obtenidos muestran que las fibras PLA-R. hymenosepalus tienen posible utilidad en aplicaciones de liberación de antioxidantes como apósitos para heridas.

In this work we report the formation of long microcrystalline linear self-assemblies observed during the thin film growth of several II-VI compounds. Polycrystalline CdTe, CdS, CdCO3, and nanocrystalline CdTe:Al thin films were prepared on glass substrates by different deposition techniques. In order to observe these crystalline formations in the polycrystalline materials, the thin film growth was suspended before the grains reached to form a continuous layer. The chains of semiconductor crystals were observed among many isolated and randomly distributed grains. Since CdTe, CdTe:Al, CdS and CdCO3 are not ferroelectric and/or ferromagnetic materials, the relevant problem would be to explain what is the mechanism through which the grains are held together to form linear chains. It is well known that some nanocrystalline materials form rods and wires by means of electrostatic forces. This occurs in polar semiconductors, where it is assumed that the attraction forces between surface polar faces of the small crystals are the responsible for the chains formation. Since there are not too many mechanisms responsible for the attraction we assume that a dipolar interaction is the force that originates the formation of chain-like grain clusters. The study of this property can be useful for the understanding of nucleation processes in the growth of semiconductor thin films.