Effect of propylene glycol, poly ethylene glycol 400 and pH on the release and diffusion of Ibuprofen from different topical bases

Abstract

This study was carried out to find the effect of propylene glycol (PG), poly ethylene glycol 400(PEG 400) and pH on the release and diffusion of Ibuprofen from different topical bases. 5% Ibuprofen was incorporated in the following bases and the release rate from these bases as in the following order:
NaCMC formula-4> methyl cellulose formula -3 > carbomer gel formula-1 > emulsion base formula-2.
The effect of propylene glycol concentrations 10%, 30% and 40% applied as in formulas 5, 6 and 7 which 40% gave the highest release, in the same time
40% of propylene glycol added as in formulas 8, 9 and 10 and only formula 10 gave significant effect and in addition to formula 7 while others had no change in Ibuprofen release. In addition to that, poly ethylene glycol 400 has been added as in formulas 11 and 12 and this combination increased the Ibuprofen release. Formula -1 has been chosen to study the effect of pH change ( 6.5 and 8) on the release process, since pH 8 gave the highest release leading to select the formulas 11, 12 and formula with pH 8 and applied them to the diffusion test by using excised mouse skin. On the other hand, preliminary clinical study was
carried out with 20 patients and the result revealed 65% of the patients gave good positive response.