Abstract
The current study describes the effect of the concentration of Span 60 (gelator) on the properties of oleogels. Mustard oil was chosen as the representative vegetable oil. Microscopy showed that an increase in the gelator concentration resulted in the increase in the gelator network density. Thermal studies (crystallization kinetics and differential scanning calorimetry) indicated a 2-stage crystallization process. An increase in the gelator proportion resulted in the increase in the compatibility amongst the oleogel components. The formation of gelator network was governed by the interaction amongst the hydroxyl groups of Span 60. A variation in the gelator proportion resulted in the alteration in the d-spacing, crystallite size and lattice strain. The variation in the above-mentioned properties was found to affect the viscoelastic properties of the oleogels as was predicted from the Weichert model. The drug release studies suggested that the drug diffusion due to the gelator network relaxation during drug release was predominant as compared to the Fickian diffusion. The results suggested that it is possible to alter not only the release profile of drugs but also the physical properties (of the oleogels) by tailoring the gelator concentration.