Physico-Mechanical and Chemical Characterization of Chitin-Based Formulation for Dermal Applications

The increase in skin rigidity is of key interest in many cosmetic applications. In this study, we intend to develop a chitin-based dermal application with a formulation to increase skin rigidity. In film formulation, the sample is sprayed on a heated surface and the pan is dried at 60 °C until all dispersions are evaporated and the film is formed. The films with 1% concentrations of chitin nanofiber, glycerol, and PVA show promising transparency, film-forming, and dispensability properties. The films were analyzed for their optical, mechanical, morphological, physical, and chemical properties. The findings reveal that the introduction of PVA and glycerol to chitin nanofiber dispersions significantly increases (p < 0.05) transparency, with a consequent reduction in film opacity compared to films containing only chitin nanofiber. Moreover, the addition of PVA and glycerol significantly increases (p < 0.05) film thickness and tensile strength in comparison to films composed solely of chitin nanofiber. Under the same strain rate, stress levels reduce, while yield strain increases with PVA and glycerol incorporation. Chitin nanofiber application on a substrate exhibits superior bending rigidity, reflected in the significantly increased (p < 0.05) relative bending rigidity and bending length compared to films with PVA and glycerol, resulting in 5.6 and 4.2 cm, respectively. The SEM micrographs showcase a fibrous network indicative of chitin nanofiber entanglement and self-assembly within the solution. Smooth areas attest to improved clarity and transparency resulting from the synergistic effects of chitin nanofiber, PVA, and glycerol. The data illustrates that the addition of PVA and glycerol leads to a significant increase (p < 0.05) in water vapor permeability and water solubility. The films exhibit a neutral pH range, suggesting chemical equilibrium. These findings emphasize chitin-based films with PVA and glycerol as a breakthrough in non-invasive dermal applications for enhanced skin rigidity.