title: Pharmacokinetic evaluation of formulated levodopa methyl ester nasal delivery systems.
abstract: The objective of this study was to investigate the pharmacokinetic characteristics of levodopa (L-dopa) from nasal powder formulations using highly water-soluble levodopa methyl ester hydrochloride (LDME). In vivo pharmacokinetic studies were carried out with formulated LDME nasal powders. After oral and intravenous administration of L-dopa and carbidopa and intranasal administration LDME to the rat, L-dopa concentrations were determined in plasma and the brain using high-performance liquid chromatography. The absolute bioavailabilities of nasal preparations with and without Carbopol were 82.4 and 66.7 %, respectively, which were much higher than that of oral delivery (16.2 %). The drug-targeting efficiencies [area under the curve (AUC) in brain/AUC in plasma] of L-dopa in the nasal formulations (0.98-1.08) were much higher than that of oral preparation (0.69). These results suggest that LDME nasal powder formulations would be useful delivery systems of L-dopa to the brain.
authors.affiliation: College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, 52 Ewhayeodae-gil, Seodaemun-Gu, Seoul, 120-750, Korea.
authors.forename: Yeon Hong
authors.initials: YH
authors.lastname: Lee
authors.forename: Kyung Hee
authors.initials: KH
authors.lastname: Kim
authors.forename: In Kyung
authors.initials: IK
authors.lastname: Yoon
authors.forename: Kyung Eun
authors.initials: KE
authors.lastname: Lee
authors.forename: In Koo
authors.initials: IK
authors.lastname: Chun
authors.forename: Jeong Yeon
authors.initials: JY
authors.lastname: Rhie
authors.forename: Hye Sun
authors.initials: HS
authors.lastname: Gwak
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D001682:Biological Availability; D002626:Chemistry, Pharmaceutical; D016503:Drug Delivery Systems; D007980:Levodopa / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D007980:Levodopa; C035420:levodopa methyl ester