Dental resin as controlled release layer for the development of an innovative long-acting intra-oral delivery system

The objective of the present study was to develop a novel long-acting intra-oral delivery system (LIDS) to overcome the frequent administration by the nonparenteral route with Huperzine A (HupA) as a model drug. HupA-LIDS was prepared using a magnetic drug delivery with dental resin as release controlling layer for long-term release of HupA. The factors that influenced the drug release comprised of the type and amount of pore formers, the speed of shaker, resin layer weight and drug loading. These factors were evaluated and optimized. The in-vitro release studies showed that the system was able to deliver HupA in an approximately zero-order kinetic. The SEM study showed that the multiple orifices on the surface of a resin layer formed due to presence of pore formers, which contributed to the HupA release. The pharmacokinetic study in rabbits demonstrated the HupA-LIDS could be released in vivo for more than 8 days with prolonged T_max and significantly reduced C_max in comparison with commercial tablets. This study provided some pioneering ideas for developing intra-oral extended release drug delivery system using dental resin as release controlling materials. The optimized HupA-LIDS can make excellent sustained release and have the potential for the long-acting product in the therapy of Alzheimer's disease.