Abstract

Background: Emulgel combines the qualities of an emulsion with those of a gel. In order to create an emulgel w/o or o/w, emulsions have to be formulated, which are then combined with a gelling agent, resulting in a dual-control drug release. Celecoxib exhibits analgesic, antipyretic and anti-inflammatory activities and is used to treat osteoarthritis, severe pain, rheumatoid arthritis, and other medical conditions.

Methods: Celecoxib Emulgel was developed and evaluated by using natural oil and carbopol- 940 as a gelling agent in different concentrations. The screening of various oils, co-surfactants and surfactants was performed to determine the solubility. The essential oils (eucalyptus oil and turpentine oil) were used as penetration modifiers. Studies on compatibility with polymers have been conducted, and the results indicate that there should be no physical or chemical interactions between the polymers and the drug substance. For the preparation of emulgel, various emulsions were prepared with Smix (cosurfactant and surfactant) ratios (1:1, 2:1 and 3:1). The selection of a gelling agent was done by incorporating the selected emulsion system ratio of 1:1 with the combinations of polymers carbapol 940, carbapol 934, and HPMC (0:1:0, 0:0.5:1, 0:0:3, 0.5:0:1, 1:0:0) gel base to make a homogenous emulgel.

Results: The emulgel was examined visually to see if it had any phase behaviour, feel, spreadability, and grittiness by applying its thin layer to a slide. Then, all six formulations of emulgel were prepared with the selected gelling agent. All emulgels were evaluated for pH, physical properties (consistency, homogeneity, colour, texture), drug content, spreadability, extrudability, swelling index, viscosity, stability and centrifugation. A Franz diffusion cell and an egg membrane were used to perform in-vitro drug release.

Conclusion: Among all prepared formulations, EG1 had a better release, higher viscosity, higher drug content, and a higher swelling index than the others. The formulation EG1 showed higher drug release (91.25%) within 8 hours.

Keywords: Celecoxib, penetration modifier, essential oils, gelling agent, NSAIDs, emulsion.

Graphical Abstract