Abstract
The current study describes development and characterization of carbopol based bigels for the iontophoretic delivery of antimicrobials. The bigels were prepared by mixing carbopol aquagel and sorbitan monostearate (SMS)-sesame oil based oleogels. The molecular characterization of the gels was done by Fourier Transform Infrared (FTIR) spectroscopy and reflectance spectroscopy. The electrical properties were investigated by impedance spectroscopy. Metronidazole (model antimicrobial) loaded bigels were evaluated for their iontophoretic delivery application. FTIR spectra suggested formation of intra/intermolecular hydrogen bonding amongst the gel components. Reflectance spectroscopy showed higher depth of absorption in the bigels containing higher amount of aquagel. The bigels were electro-conductive in nature. The gels containing higher oleogel composition, showed higher bulk resistance and lower drug release. The iontophoretic delivery study showed 1338% increase in the release of metronidazole under the influence of constant current source. The drug release study of the gels suggested that the gels can be used as matrices for iontophoretic drug delivery applications.