A novel and multifunctional excipient for vaginal drug delivery

The present study explores the pharmaceutical potential of a natural organic matter (fulvic acid) for sustained release, acid buffering capacity and mucoadhesion in vaginal drug delivery. The antifungal drug, Itraconazole, was first converted into inclusion complexes with fulvic acid (1:1 & 1:2 molar ratio) and then characterized byDifferential Scanning Calorimetry (DSC), X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT IR) and Mass Spectroscopy. Results were also authenticated by conformational analysis.Solubility analysis of complexes yielded different thermodynamic parameters and explained the driving force for solubilisation when the pH was varied in an acidic range. MTT assays were also performed to assess the potential in vitro cell toxicity of the complexes in comparison to the neat drug. The complexes were then formulated into tablets and optimized for hardness, mucoadhesion and release profiles. The optimized tablets presented with satisfactory mucoadhesion, acid buffering and spreading ability. Moreover, the antifungal activity of the formulation was also increased due to improved aqueous solubility of the drug despite the larger size of the complex. The study also indicated the potential use of fulvic acid as a functional excipient in the preparation of a vaginal drug delivery system (VDDS).