Use of solid dispersions to increase stability of dithranol in topical formulations

• Type: Article in International Scientific Journal
• Date: 2014

Authors

Marilene Estanqueiro (Author) Other; Jaime Conceicao (Author) Other; Maria Helena Amaral (Author) FFUP; Jose Manuel S Sousa Lobo (Author) Other

Journal

Title: Brazilian Journal of Pharmaceutical Sciences

Vol. 50

Pages: 583-590

ISSN: 1984-8250

Publisher: Universidade de São Paulo

Indexing

ISI Web of Knowledge - 2 Citations

Scopus - 4 Citations

Scientific classification

FOS: Medical and Health sciences > Basic medicine

CORDIS: Technological sciences > Technology > Pharmaceutical technology

Other information

Authenticus ID: P-009-YZN

DOI: 10.1590/s1984-82502014000300018

Abstract (EN): The present study was planned to improve the stability of dithranol using solid dispersions (SD). Two different SD at a 1: 9 ratio of dithranol/excipient were prepared: one of them using glyceryl behenate as excipient and the other using a mixture of argan oil with stearic acid (1: 8 ratio) as excipient. Pure dithranol and SD of dithranol were incorporated in an oil-in-water cream and in a hydrophobic ointment in a drug/dermatological base ratio of 1: 10. The physical and mechanical properties of semisolid formulations incorporating the pure drug and the developed SD were evaluated through rheological and textural analysis. To evaluate the stability, L*a*b* color space parameters of SD and semisolid formulations, and pH of hydrophilic formulations were determined at defined times, during one month. Each sample was stored at different conditions namely, light exposure (room temperature), high temperature exposition (37 degrees C) (protected from light) and protected from light (room temperature). Despite higher values of firmness and adhesiveness, hydrophobic ointment exhibited the best rheological features compared to the oil-in-water cream, namely a shear-thinning behavior and high thixotropy. These formulations have also presented more stability, with minor changes in L*a*b* color space parameters. The results of this study indicate that is possible to conclude that the developed SD contributed to the increased stability of dithranol.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8