Improvement in Skin Penetration Capacity of Linalool by Using Microemulsion as a Delivery Carrier: Formulation Optimization and In Vitro Evaluation

• Published in: Pharmaceutics 2023-05, Vol.15 (5), p.1446
• Main Authors: Tsai, Ming-Jun, Chang, Wen-Yu, Chiu, I-Hui, Lin, I-Ling, Wu, Pao-Chu
• Format: Article
• Language: English
• Subjects: Alcohol; Analysis; Design; Drug delivery systems; Drugs; Evaluation; Microemulsions; mixture design; permeation capacity; Pharmaceuticals; response surface methodology; Skin; Skin care products; stability; Surfactants; topical application; Variables; Vehicles; Viscosity
• ISSN: 1999-4923; 1999-4923
• DOI: 10.3390/pharmaceutics15051446

Linalool is an aromatic oil with analgesic, anti-inflammatory and anti-UVB-induced skin damage effects. The aim of this study was to develop a linalool-loaded microemulsion formulation for topical application. In order to quickly obtain an optimal drug-loaded formulation, statistical tools of the response surface methodology and a mixed experimental design with four independent variables of oil (X ), mixed surfactant (X ), cosurfactant (X ) and water (X ) were used to design a series of model formulations in order to analyze the effect of the composition on the characteristics and permeation capacity of linalool-loaded microemulsion formulations and to obtain an appropriate drug-loaded formulation. The results showed that the droplet size, viscosity and penetration capacity of linalool-loaded formulations were significantly affected by formulation component proportions. The skin deposition amount of the drug and flux of such formulations expressively increased about 6.1-fold and 6.5-fold, respectively, when compared to the control group (5% linalool dissolved in ethanol). After 3 months of storage, the physicochemical characteristics and drug level did not show a significant change. The linalool formulation-treated rat skin showed non-significant irritation compared to skin treatments in the distilled-water-treated group. The results showed that specific microemulsion applications might be considered as potential drug delivery carriers for essential oil topical application.