Technological and Biopharmaceutical Characterization of Carbopol-Based Ketoprofen Emulgels

  Objective: Emulgels are a combination of emulsions and gels. In this study, the influence of different oil phases and gelling agent concentrations on the technological and biopharmaceutical characteristics of prepared emulgels is assessed. Materials and Methods: Light liquid paraffin (various concentrations), cetyl alcohol, isopropyl myristate, and almond oil were used in the oil phase of the emulsions, and Carbopol® 940 (0.5%, 0.75%, and 1% w/w concentrations) was used as the gelling agent for the gel base. The prepared emulgels were characterized in terms of pH, rheological behavior, spreadability, and in vitro release of ketoprofen. Results and Discussion: All formulations produced stable, white, semisolid forms with smooth homogeneous textures and no phase separations. The pH of the resulting emulgels ranged from 5.5 to 6.5. An increase in the carbopol concentration led to an increase in viscosity, and all prepared emulgels exhibited pseudoplastic flow. The spreadability of semisolid dosage forms improved by reducing the concentration of the gelling agent. Results from the in vitro study indicated that 88.48%-99.11% of the ketoprofen was released within 150 min. Conclusion: The prepared emulgels are in semisolid form, and hence suitable for topical application.