PREPARATION, RELEASE, RHEOLOGY AND STABILITY OF PIROXICAM EMULGEL
Objective: The purpose of this work was to develop and optimize the emulgel formulation of piroxicam with two types of gelling agent chitosan and xanthan gum. The release profiles of prepared formulas were investigated. In addition, the rheology and stability of the best formula were investigated.
Methods: Emulsified piroxicam was prepared to use oleic acid, tween 80 and PG with a ratio (3:10:10). In xanthan based emulgel, the xanthan gum (1% and 1.5%) was spread as powder on emulsified piroxicam with stirring until emulgel was formed. In chitosan-based emgels, Chitosan gel was added to emulsified piroxicam and stirring until the Emulgel was constructed. Chitosan gels were prepared by incorporating different concentration, 2%, 3%, 6% w/v of chitosan in 1% v/v of glacial acetic acid in distilled water. In vitro release of piroxicam from different formulas was conducted in 300 ml phosphate buffer pH 7.4, at a speed of 120 rpm at 37Â±2Â°C. The amount of the drug released from the bases was determined spectrophotometrically at 504 nm. Viscometer Myr. Vr 3000 was used to measure the viscosity of the prepared formulas. The prepared formulas were stored in well-stoppered polyvinyl chloride (PVC) plastic containers in the dark for 6 mo at room temperature. They were checked for drug content, viscosity, and pH change bimonthly throughout the period.
Results: The results showed that the dissolution increases significantly with increasing the concentration of xanthan. Chitosan has significant synergized the enhancements of xanthan gum in the release. Rheological behaviour of the selected formula containing chitosan (2%) and xanthan gum (1.5) had shear thinning in nature showing a decrease in viscosity at the increasing shear rates. The selected formula was stable 6 mo at 40ËšC/75% RH and 4ËšC. The formula found was yellow viscous creamy preparation with the smooth homogenous appearance. The pH and the drug release was also found to be stable under storage conditions.
Conclusion: Piroxicam release can be improved by preparing emulgel which stable and have good rheologic properties.
2. Meenakshi D. Emulgel A novel approach to topical drug delivery. Int J Pharma Bio Sci 2013;4:847-56.
3. Latha S, Sridevi G. Role of polymers as gelling agents in the formulation of emulgels. Polymer Sci 2016;2:1.
4. Singh B, Kumar S, Shafaat K. Development and characterization of a nanoemulsion gel formulation for transdermal delivery of carvedilol. Int J Drug Dev Res 2012;4:151-61.
5. Kristl J, Smid-Korbar J, Struc E, Schara MV, Rupprecht H. Hydrocolloids and goals of chitosan as drug carriers. Int J Pharm 1993;99:13-9.
6. Abd-Allah F, Dawaba HM, Ahmed AMS. Preparation, characterization, and stability studies of piroxicam loaded microemulsions in topical formulations. Drug Discoveries Ther 2010;4:267-75.
7. Maheswaran A, Padmavathy J, Nandhini V, Saravanan D, Angel P. Formulation and evaluation of floating oral in situ gel of diltiazem hydrochloride. Int J Appl Pharm 2016;9:50.
8. Kini AG, Dixit M, Kulkarni PK. Enhancement of solubility and dissolution rate of poorly water-soluble drug by spray drying using different grades of chitosan. Int J Pharm Pharm Sci 2011;3:231-5.
9. Nur A, Mohamed N, Yagoub N. Comparative evaluation of xanthan, guar and treated guar gums as drug release barriers in oral matrices. Int J Pharm Pharm Sci 2015;7:436-40.
10. Dasgupta S, Mazumder B, Ghosh S, Kaurav S. Solid lipid nanoparticles (SLNs) for topical delivery of aceclofenac by using xanthan gum: ex vivo and in vivo evaluation. Curr Drug Delivery 2013;10:11.
11. Rao M, Sukre G, Aghav S, Kumar M. Optimization of metronidazole emulgel. J Pharm 2013;1:1.