Table of Contents
ISRN Pharmaceutics
Volume 2011, Article ID 838016, 6 pages
Research Article

Improving the Isotretinoin Photostability by Incorporating in Microemulsion Matrix

1Indukaka Ipcowala College of Pharmacy, New Vallabh Vidyanagar, Anand, Gujarat 388 121, India
2A. R. College of Pharmacy and G. H. Patel Institute of Pharmacy, Vallabh Vidyanagar, Anand, Gujarat 388 120, India
3Institute of Science and Technology for Advance Studies and Research, Vallabh Vidyanagar, Anand, Gujarat 388 120, India

Received 13 April 2011; Accepted 11 May 2011

Academic Editor: H. Arima

Copyright © 2011 Mrunali R. Patel et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The present paper demonstrates the increased photostability of isotretinoin when loaded in microemulsion. The photodegradation of isotretinoin, in methanol and microemulsion formulation was studied under direct sun light. The photodegradation process was monitored by UV spectrophotometry. In methanol solution, isotretinoin undergoes complete photodegradation just within a few minutes of light exposure. Isotretinoin incorporated in microemulsion formulation showed an increased stability in comparison to the methanol solutions. In particular for isotretinoin, a residual concentration of 75% was still present after a light irradiance versus a residual value of just 16% measured at the same time in methanol solution. Further, degradation kinetic parameters of isotretinoin-loaded microemulsion formulation were demonstrated increase isotretinoin half-life about five-times in comparison with a methanol solution under a direct sun light.