LAUSR

ABSTRACT The present study aimed to develop a celecoxib (CEL) nanoparticle with improved dissolution/dispersion and consistent absorption even in the presence of impaired gastric motility. CEL was pulverized by a wet‐milling with hydroxypropyl cellulose (HPC), and the prepared nanoparticles were physicochemically characterized after freeze‐drying. CEL nanoparticle with HPC‐SSL (NP/CEL) exhibited better dissolution/dispersion behavior in pH1.2 solution compared with CEL nanoparticles with other polymers, as evidenced by a 21.8‐fold higher initial dissolution/dispersion rate than crystalline CEL. The mean particle diameter of water suspended‐NP/CEL was 250nm, and the CEL nanoparticle existed in an amorphous state. Even after storage at 40°C for 4weeks, there were no significant changes in the dissolution/dispersion behavior. Oral absorption of CEL samples (5mg‐CEL/kg) was evaluated in normal and propantheline (PPT)‐treated rats with simulated gastric motility impairment. In PPT‐treated rats, oral crystalline CEL led to a decrease in oral absorption by 12% of the AUC0–4 compared with that in normal rats, whereas NP/CEL suppressed the pharmacokinetic transition of CEL by 43% of the AUC0–4 due to the improved dissolution/dispersion behavior of CEL. The NP/CEL system might be promising to avoid decreased absorption of CEL caused by impaired gastric motility.