Tridimensional Alginate Films with Cat’s Claw (Uncaria tomentosa) Extract or Aloe Vera (Aloe barbadensis) Gel for Potential Use as Wound Dressings

Active compounds of plants are of great interest for biomedical use. Cat’s claw (Uncaria tomentosa) is a woody vine plant from the Peruvian rainforest known for its anti-inflammatory, anti-arthritic and anti-asthmatic properties. Meanwhile, aloe vera (Aloe barbadensis) is a plant commonly used for wound healing and skin hydration.

In this study, we elaborated microparticles from an emulsion made of alginate solutions with aloe vera gel or cat’s claw extract and poloxamer 407 as a stabilizing agent with ultrasound. Then, tri-dimensional membranes were obtained by solvent evaporation and, finally, crosslinked in a calcium chloride solution to improve their mechanical properties.

The 27 to 33 µm-thick membranes showed a porous surface on a scanning electron microscope (SEM) which is significantly different to membranes with no microparticles. The contact angle of water on the membranes showed an increase in hydrophilicity due to the use of aloe vera gel. Furthermore, the presence of aloe vera also improved water absorption in an acetate buffer (pH 5.5) at 37.5˚C. Finally, the presence of cat’s claw extract in the microparticles significantly enhanced radical scavenging, which was measured by ABTS decoloration assay, in comparison to tri-dimensional alginate membranes with no active compounds.