Novel user-friendly night care spray to manage skin darkening.

Abstract

Hyperpigmentation can be either diffused or localized. In treating diffused hyperpigmentation, larger surface area coverage is the requirement. Novel user-friendly spray formulation loaded with depigmenting agents can cater the night time need in treating skin darkening. Kojic acid and arbutin, the selected actives for the study exhibit low permeability and high irritancy generating hurdles in topical delivery. The aim of this study was to develop novel kojic acid and arbutin-loaded spray formulation as a night care product. "Thermosensitive gel spray" was fabricated by simple industry feasible cooling technique and evaluated for its ability to improve skin retention, penetration, improved anti-tyrosinase activity, and suppressed dermal irritancy. Comparative in-vitro and ex-vivo release profile showed the marked effect of poloxamer 407 and Methocel K100M in improving penetration and extending release over longer time period. Retention of actives in the skin layer was found to be eight times more in case of thermosensitive gel spray as compared to conventional gel formulation. The thermosensitive gel spray was free from any dermal irritancy and had higher tyrosinase inhibitory effect as against conventional gel. Furthermore, thermosensitive gel spray exhibited good stability and did not show any change in morphology and drug content during the 3-month storage. Kojic acid and arbutin-loaded thermosensitive gel spray can prove to be a promising strategy to treat hyperpigmentation.