IN-VITRO EVALUATION OF IBUPROFEN RELEASE KINETICS FROM WITEPSOL SUPPOSITORIES
Mosbah A. El-Majri and Mokhtar M. El-Baseir*
ABSTRACT
The aim of this work is preparation and characterisation of Witepsol (H5, H15, E75 and W35) suppository formulae containing ionic surfactants (cetrimide and pharmagel B and sodium lauryl sulfate) and non-ionic surfactants (Brij35, Myrj52 and Tween 20). Suppositories were prepared using melt cream method and tested for the physicochemical parameters using British Pharmacopeia (B.P) methods. Release kinetic studies of ibuprofen as a model drug from suppositories were carried out at 37 ± 0.5°C in buffer phosphate as dissolution media. All prepared suppositories were found to satisfy B.P, requirements for liquefaction time, hardness values, disintegration time and content uniformity. The amounts of drug released in 200 min from Witepsol (H15, E75,
W35 and H5) W35 and WH5 based suppositories were 65% w/w, 60%w/w, 30%w/w and 23% w/w respectively. Incorporation of Pharmagel B, sodium lauryl sulfate, Myrj52 and Tween 20 surfactants within Witepsol H15 base, significantly enhanced the amount of the ibuprofen released. In this respect sodium lauryl sulfate and Myrj 52 were among the tested ionic and nonionic surfactants found to be superior as additive in preparing ibuprofen suppositories as the released amount of ibuprofen was 95% w/w and 89% w/w in 200 min. Analysis of release kinetics data using different mathematical models indicated that the release of ibuprofen from suppositories containing 1% of surfactant could follow more than one mechanism depending on the base matrix mixture.
Keywords: Witepsol, Ibuprofen, Suppositories, Surfactants. Release kinetics.
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