Formulation of Aloe vera based curcumin topical gel and its in-vitro evaluation

Curcumin is a polyphenolic compound obtained from the rhizome of plant. Curcuma longa possesses antioxidant, anti-inflammatory and wound-healing properties. The current study was designed to formulate an Aloe vera-based curcumin topical gel. To enhance curcumin's solubility, it was first complexed with β-cyclodextrin, given its hydrophobic nature. While Carbopol, carboxy methyl cellulose and guar gum were used in various concentrations as gelling agents for preparation of the formulations. The effect of propylene glycol as a permeation enhancer was also observed. The prepared formulations were tested for different parameters such as physical appearance, spreadability, drug content, pH, viscosity and in-vitro permeation. All the formulations were found to be stable. All formulations consisting of propylene glycol showed permeation within the range of 80-90%. The maximum percentage of drug release was observed in the formulation containing 1% Carbopol 940 as the gelling agent which also exhibited good spreadability. In comparison to gels formulated with carboxymethyl cellulose and guar gum, Carbopol 940 gels appeared more translucent. Consequently, it was concluded that curcumin's permeation improved following its complexation with β-cyclodextrin. This complex when further used for the formation of an aloe vera based topical gel with 1% Carbopol 940 and 10% propylene glycol demonstrated maximum efficacy.