Design, characterization, and evaluation of intranasal delivery of ropinirole-loaded mucoadhesive nanoparticles for brain targeting.

CONTEXT: Parkinson disease (PD) is a common, progressive neurodegenerative disorder, characterized by marked depletion of striatal dopamine and degeneration of dopaminergic neurons in the substantia nigra. OBJECTIVE: The purpose of the present study was to investigate the possibility of targeting an anti-Parkinson's drug ropinirole (RH) to the brain using polymeric nanoparticles. MATERIALS AND METHODS: Ropinirole hydrochloride (RH)-loaded chitosan nanoparticles (CSNPs) were prepared by an ionic gelation method. The RH-CSNPs were characterized for particle size, polydispersity index (PDI), zeta potential, loading capacity, entrapment efficiency in vitro release study, and in vivo distribution after intranasal administration. RESULTS AND DISCUSSION: The RH-CSNPs showed sustained release profiles for up to 18 h. The RH concentrations (% Radioactivity/g) in the brain following intranasal administration (i.n.) of RH-CSNPs were found to be significantly higher at all the time points compared with RH solution. The concentration of RH was highest in the liver (7.210 ± 0.52), followed by kidneys (6.862 ± 0.62), intestine (4.862 ± 0.45), and lungs (4.640 ± 0.92) in rats following i.n. administration of RH-CSNPs. Gamma scintigraphy imaging in rats was performed to ascertain the localization of drug in the brain following intranasal administration of formulations. The brain/blood ratios obtained (0.251 ± 0.09 and 0.386 ± 0.57 of RH (i.n.) and RH-CSNPs (i.n.), respectively) at 0.5 h are indicative of direct nose to brain transport, bypassing the blood-brain barrier (BBB). CONCLUSION: The novel formulation showed the superiority of nose to brain delivery of RH using mucoadhesive nanoparticles compared with other delivery routes reported earlier.