Nanoemulgel Formulation of Tetrahydrocurcumin with Efficient Anti-inflammatory Effect for the Treatment of Skin Disorders

Introduction: Tetrahydrocurcumin (THC) is a partially reduced white metabolite of curcumin which does not impart yellowish colour on skin due to which it seemed to be a promising topical agent compared to curcumin which discoloured the skin with long lasting visible mark. Objectives: The research work was intended to formulate THC loaded Nano Lipid-based (TNL) Carbopol Gum Gel (TNLCG) also called tetrahydro curcumin nanoemulgel and to investigate its therapeutic efficacy against inflammation using animal model. Materials and Methods: TNLCG was prepared based on pseudoternary phase-diagram with solubilizing capacity of tocopheryl acetate (10% w/w) and emulsifying combination of tween 80: polyethylene-glycol 400 (2:1 in 35% w/w) in 45% w/w aqueous phase with Carbopol 934 gel base. Selected formulations were evaluated for various parameters using in-house developed HPLC analytical method (at 280nm). Results: Nanoemulgel was found to be a stable formulation which significantly improved cellular absorbency with tocopheryl acetate with high concentration of THC for treating skin inflammation. Significant increase in the steady state flux (Jss) of 41µg/cm 2 /h, permeability coefficient (Kp) of 1.08 and Enhancement ratio (Er) of 3.7 were observed. The TNLCG demonstrated 77.36% in vitro drug release, significant skin permeability and optimal properties including spherical shape with 129nm nanosize, adequate zeta potential (-21.45mV), and PDI value of 0.18. Conclusion: This study revealed encouraging outcomes for TNLCG formulation as a novel tool for safe delivery of THC. According to the findings of the preceding research, it can be an effective therapeutic formulation which offers significant inflammation reducing activity with good moisturising quality.