Mucoadhesive buccal films for treatment of xerostomia prepared by coupling HME and 3D printing technologies

Polyethylene oxide-based muco-adhesive buccal films containing adipic acid active pharmaceutical ingredient (API) and xylitol were developed using hot-melt extrusion (HME) coupled with Fused Deposition Modeling (FDM) three-dimensional (3D) printing. The immediate release mucoadhesive buccal films are intended for treatment or amelioration of xerostomia (dry mouth condition). Different formulae containing adipic acid and xylitol as the main saliva stimulating ingredients, and polyethylene oxide N80 (Polyox-N80) as the polymeric carrier were extruded using Thermo Scientific (TM) Process 11 Parallel Twin-Screw Extruder by Thermo Fisher Scientific (Waltham, MA, USA) equipped with 1.5 mm die. The extrudates were evaluated for printability using 3-point bend test and the ones which exhibited appropriate mechanical strength were 3D printed using Prusa i3 MK3 S 3D printer at 50 degrees C bed temperature, and 200 degrees C extruder temperature. The printed films demonstrated uniform content of adipic acid and desirable drug release upon quantification by high performance liquid chromatography. More than 80% of the adipic acid was released in 15 min and 100% of the adipic acid was released within 30 min. The DSC thermographs of the printed formulations revealed the adipic acid was dispersed in the polymer. The results of this study present an alternative formulation approach for the treatment of xerostomia by combining HME with FDM-3D printing for the development of muco-adhesive films containing adipic acid and xylitol.