Development of stable tocopherol succinate-loaded ethosomes to enhance transdermal permeation: In vitro and in vivo...

Tocopherol succinate (TS) represents synthetic derivative of α-tocopherol (vitamin E), it act as anti-aging, moisturizing, and antioxidant. Ultraviolet (UV) photo stability of TS is low, and it cause skin irritation.

To develop tocopherol succinate loaded ethosomal gel for topical TS delivery and to evaluate its moisturizing and anti-aging effects.

Cold method technique was used to produce ethosomal formulations (N = 9) by varying ethanol and lipid concentrations (F1-F9). The most optimized formulation (F5) was selected for further study on the basis of characterization. F5 Formulation was incorporated into gel. Ex vivo permeation study was done by using Franz diffusion cell. Non-invasive in vivo study was performed using corneometer for the evaluation of skin moisture content and skin mechanical properties by using cutometer, for 12 weeks on human subjects (N = 13).

Particle size (PS), zeta potential (ZP) and polydispersity index (PDI), Entrapment efficiency were found to be 179.1 nm, -13.7 mV and 0.345, and 99.71%, respectively. Transmission electron microscopy (TEM) depicted spherical ethosomal particles. Ethosomal gel and control gel were evaluated for conductivity and pH. Rheological analysis revealed a non-Newtonian flow. The release profile showed initial burst and then, sustained release, release data followed Korsmeyer-Peppas model. TS-loaded ethosomal gel appeared physically stable and showed significant results in terms of skin capacitance and mechanical properties.

The prepared ethosomal gel formulation containing TS is more stable with enhanced antioxidant, moisturizing properties, and increased TS deposition into the skin layer.