Improvement of cutaneous delivery of methylene blue by liquid crystals

Publication date: 5 September 2018Source: International Journal of Pharmaceutics, Volume 548, Issue 1Author(s): Maria Teresa Junqueira Garcia, Thalita Pedralino Gonçalves, Éricka São Félix Martins, Tereza Silva Martins, Márcia Carvalho de Abreu Fantini, Paulo Roberto Regazi Minarini, Sandra Costa Fernandez, Giovanna Cassone Salata, Luciana Biagini LopesAbstractThe purpose of this study was to evaluate the effect of composition and characteristics of liquid crystalline phases (LCPs) on cutaneous delivery of methylene blue (MB). LCPs were obtained by mixing Brij97® with water at various ratios; Brij97®:water at 8:2 (F8:2), 7:3 (F7:3), and 6:4 (F6:4) were selected, and MB was incorporated at 0.1%. F8:2 and F7:3 exhibited textures and small angle X-ray scattering (SAXS) patterns corresponding to lamellar phase, whereas F6:4 displayed characteristics of hexagonal phase. All three LCPs were stable for 9 months, and exhibited thixotropic pseudoplastic behaviour. Increasing water content increased viscosity. All three LCPs released less (3.2- to 6.6-fold) MB than control gel (3.0% hydroxyethylcellulose (HEC) + 0.1% MB), demonstrating their ability to sustain release. Despite the lower release, all LCPs improved skin retention of MB at 6 h post-application (1.3- to 2.1-fold) compared to the control gel. Among the LCPs, F8:2-mediated skin retention of MB was more pronounced, followed by F7:3. Consistent with the increased penetration, transepidermal water loss (TEWL) als...
Source: International Journal of Pharmaceutics - Category: Drugs & Pharmacology Source Type: research