Preparation and evaluation of a polycaprolactone-gelatin-alginate membrane for application to wounds skin..

Abstract

Skin wounds are an alteration of the normal anatomical structure and function. This can range from a simple breach in the epithelial integrity of the skin to more profound damage to other structures such as tendons, muscles, blood vessels, nerves, and even bones. Acute wounds (burns) and chronic wounds (ulcers) constitute a national public health problem. Skin substitutes have become a topic of great interest due to their potential to improve wound healing, reduce inflammation, and promote cell proliferation and tissue regeneration. We propose the development of an electrospun polycaprolactone-gelatin-alginate membrane for application in skin wounds. To develop the electrospun membrane, solutions of polycaprolactone (PCL) and gelatin (GEL) were prepared by dissolving PCL (19% w/v) in aqueous solution. Acetic acid and incorporating the appropriate amount of GEL to obtain PCL-GEL and PCL-GEL-ALG (Alginate) solutions with a final ratio of PCL (61:29%), GEL (28.8%) and Alg (12.9%) w/v, respectively. A solution of only PCL in Acetic Acid (19% w/v) was also prepared. Electrospinning was performed using a horizontal instrument assembled in the INR Biomaterials laboratory, where the electrospun fibers (membranes) were recognized on a static aluminum plate. After electrospinning, the membranes were removed from the collector and sterilized under ultraviolet (UV) light for 15 minutes on each side. Scanning Electron Microscopy (SEM) was used to observe the morphology of the electrospun fibers. To determine cell biocompatibility, dermal fibroblasts were seeded on the electrospun membranes and analyzed using the Calcein Am (Invitrogen®) assay, following the manufacturer's instructions. Regarding the macroscopic appearance of the membranes, we can mention that the three membranes present a white color, are flexible, resistant to handling, and soft to the touch, with a thickness close to 2000 µm for PCL, 1000 µm for PCL-Gel, and 320 µm for PCL-GEL-ALG. Furthermore, according to SEM micrographs, the membranes present a homogeneous fibrillar morphology with random orientation, in addition to presenting interconnected porosity. We also observed that the incorporation of GEL and GEL-ALG to the PCL increased the diameter of the fibers. To determine whether the membranes were cytotoxic, a cell viability assay was performed with dermal fibroblasts. We observed that after 24 hours of seeding dermal fibroblasts on the electrospun membranes, they had no cytotoxic effect on these cells. Likewise, membranes seeded with dermal fibroblasts for up to seven days did not have a cytotoxic effect. Furthermore, the membranes covered the surface of the electrospun membranes and were also found within the membranes, displaying a three-dimensional structure. These cells proliferated for seven days in cell culture. Although all three membranes kept the cells alive, the micrographs showed different proportions of cells distributed within them.
We obtained an electrospun PCL-GEL-ALG membrane with a good biocompatibility response with dermal fibroblasts, demonstrating its ability to support dermal fibroblasts and potentially potentially be used in skin lesions.