Novel organogel based lyotropic liquid crystal physical gels for controlled delivery applications

Abstract

In this study, novel organogel based lyotropic liquid crystals (LLC) were prepared and investigated as controlled release matrices. The LLC gels were prepared using mixtures of Span 80-Tween 80 (1:2 w/w), aqueous solution of polyvinyl alcohol (10% w/w) and sesame oil. The prepared gels were characterized by microscopy, mechanical testing and thermal studies. The biocompatibility of the gels was tested against human keratinocytes. Metronidazole loaded gels were used for in vitro drug release and antimicrobial tests. The formation of water-in-oil emulsion gels was confirmed by fluorescent microscopy. Polarized micrographs showed the formation of lamellar structures within the aqueous phase of the matrices. Mechanical studies confirmed the viscoelastic nature of the gels with solid like consistency. The melting points of the gels were in the range of 44-51 C. The gels did not elicit any cytotoxic effect on the human keratinocytes. The release of metronidazole from the gels was diffusion mediated. The drug loaded gels showed good antimicrobial efficacy against Escherichia coli. 2015 Published by Elsevier Ltd.