Vitamin D-loaded lipid nanoparticles: antioxidant properties, preparation, optimization, and in vitro...

Vitamin D₃-loaded lipid nanoparticles (Vit D₃-LNP), integrated into an azulene cream, were developed to enhance the topical delivery and stability of Vitamin D₃. The LNP was formulated using a lipid mixture and hot homogenization-ultrasonication, with comprehensive characterization revealing a particle size of 153.9 nm, a high zeta potential (-54.3 mV), and a PDI of 0.216, which TEM confirmed. Encapsulation efficiency was high (96.98%), indicating successful incorporation of Vitamin D₃ within the lipid matrix. Stability studies revealed the impact of light exposure on Vitamin D₃ degradation. In vitro, release, and skin penetration studies using Franz diffusion cells and two-photon microscopy demonstrated enhanced drug permeation and retention in deeper skin layers with the cream formulation. Cell Viability test confirmed high cell viability (~ 80-100%) for both free Vitamin D₃ and the LNP formulation; also inflammation test showed a significant reduction in ROS levels with Vitamin D₃-LNP treatment. These findings highlight the therapeutic value of LNP in managing conditions like Vitiligo, providing insights into the design of stable, effective Vitamin D₃ delivery systems for dermal applications, and offering a promising approach for advanced skin treatments.