Preparation and in vitro characterization of polyvinylpyrrolidone-poloxamer polymeric synergy for oral drug delivery

The prospect of carrying out this study was to prepare and characterize an optimized polyvinylpyrrolidone (PVP)-poloxamer (PLX) hydrophilic polymeric blend for improved solubility of poorly water-soluble drugs. Levodropropizine (LDP) was used as a model drug in this research. Several LDP-loaded PVP-PLX formulations were fabricated via the solvent evaporation method, and tested for solubility and dissolution of LDP in water. Other physicochemical characterization was accomplished using X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Amongst all the formulations tested, the one composed of LDP, PVP and PLX at the ratio of 25/37.5/37.5 (w/w/w, %) gave the highest solubility (~ 470.96 ± 23.84 mg/ml) and dissolution (~ 95% in 15 min) of LDP in the aqueous media. Furthermore, LDP existed in the amorphous state in this formulation with no strong chemical interactions with the components of polymeric blend. The morphological investigations revealed that the particles of this formulation had irregular shapes and surfaces. Thus, the abovementioned optimized hydrophilic polymeric blend, composite or synergist might be a suitable oral delivery system for numerous other poorly water-soluble drugs as well.