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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.

GRAPHICAL ABSTRACTThe current study deals with the characterization of sunflower oil-and protein-based bigels for drug delivery applications. Span-40 was used as an organogelator for the preparation of bigels. The bigels were characterized by microscopy, XRD, thermal, texture studies and impedance spectroscopy. The microscopic studies revealed that the droplets were apolar in nature (organogels), while the continuum phase was polar in nature (protein hydrogel matrix). Incorporation of the proteins improved the stability of the bigels. The release of the drugs followed diffusion kinetics. The bigels showed good antimicrobial efficiency against E.coli and were cytocompatible in presence of L929 cells.

stress (either thermal or mechanical) was introduced, the strength of the oleogels was decreased due to the syneresis of oil through the pores. An increase in the Tween 20 concentration-dependent relaxation of the oleogels was also observed due to the polymorphic change and arrangement of the gelators.

The present study delineates the effect of stearic acid on the properties of stearyl alcohol oleogel. Herein, a series of oleogels were prepared by mixing different proportions of fatty alcohol (Stearyl alcohol; gelator) and fatty acid (stearic acid; co‐gelator). The characterization of the oleogels was done by thermal, macro‐scale stress relaxation, drug release, and antimicrobial studies. The oleogels were formed by the self‐assembly of stearyl alcohol/stearic acid. Thermal studies indicated that the stearic acid alters the crystal morphology, polymorphic transition and rate of crystallization of stearyl alcohol. The firmness of the oleogels with higher stearic proportion was better, which was due to the formation of a rigid network structure of stearyl alcohol in the presence of stearic acid. The release of ciprofloxacin hydrochloride, model drug, from the oleogels was better from the oleogels with higher stearic acid content. The release of the drug from the oleogels was Fickian diffusion‐mediated; except the oleogel with the highest stearic acid proportion. The antimicrobial study showed that the drug loaded oleogels were able to resist the growth of Escherichia coli, model microbe.