Poly(vinyl pyrrolidone)–poloxamer-188 solid dispersions prepared by hot melt extrusionThermal properties and release behavior

Poly(vinyl pyrrolidone) (PVP)/poloxamer-188 blends were used as appropriate carriers for the preparation of solid dispersions by hot melt extrusion using aripiprazole (ARIP) as a poor water-soluble model drug. The physical state of ARIP in solid dispersions and its dissolution characteristics were tested for different drug contents and various PVP-to-poloxamer ratios. From TG analysis it was found that all materials were stable at the tested extrusion temperature conditions (110–120 °C) while amorphous drug dispersions were prepared in all cases, due to the miscibility of the polymer matrix with ARIP drug. Furthermore, hydrogen bonds were identified between ARIP (>N–H) and PVP (>C=O) using FT-IR analysis. Finally, ARIP dissolution rate from SDs was pH dependant and increased as the drug content decreased.