Kojic Acid Penetration: Effect of Carbomer - Tween 80 Agregate Formation

Kojic acid is well known as a depigmentation agent is used for hyper-pigmentation therapy. The objective of this study was to determine the effect of Carbomer-Tween 80 aggregate on kojic acid penetration. Kojic acid is quickly absorbed through the skin, remaining on the epidermis not long enough to inhibit melanogenesis activities; Carbomer-Tween 80 aggregate was used to control the release of kojic acid. Tween 80 was added in different concentrations (0.01% for F1, 0.02% for F2, and 0.04% for F3) to carbomer (0.25%) dispersion to create aggregate, then the aggregate was added to a vanishing cream base. Kojic acid penetration was observed by measuring the inhibition activity of tyrosinase. The inhibitor activity was determined by measuring the absorbance of dopachrome, a product of tyrosinase reacting to L-tyrosine as a substrate, and with kojic acid as an inhibitor. The value of inhibition percentage for the formulas without Carbomer-Tween 80 aggregates, F1, F2, and F3 was 64.8367 ± 3.16, 67.2833 ± 1.89, 71.0867 ± 4.05, and 49.2867±2.75%, respectively. The inhibition percent of F3 (with addition of 0.04% Tween 80) was significantly lower than the others, demonstrating that increasing Tween 80 concentrations decreases kojic acid penetration.