title: Electric impedance method for evaluation of the release property of calcein-encapsulated liposomes.
abstract: This paper is concerned with the study on development of a novel method for evaluation of the liposomes release property by measuring the electric impedance changes of liposome suspensions. Calcein/NaOH encapsulated liposomes (calcein-liposomes) were prepared with deionized water and were treated with ultrasonic irradiation in order to investigate the release property of the liposomes. To validate the proposed impedance measuring method, the calcein release rates were evaluated both by the impedance changes and the fluorescence intensity changes in calcein-liposome suspensions. With the comparison of these results obtained by the two methods, it is shown that the impedance method has much wider detecting concentration range than the fluorescence one. Furthermore, the impedance method can be efficiently used for evaluation of the release property on various ionic substances encapsulated within liposomes.
authors.affiliation: Department of Mechanical Engineering, Faculty of Engineering, Yamaguchi University, Tokiwadai 2-16-1, Ube, Yamaguchi, 755-8611, Japan.
authors.forename: Guoming
authors.initials: G
authors.lastname: Chen
authors.forename: Zhongwei
authors.initials: Z
authors.lastname: Jiang
authors.forename: Makoto
authors.initials: M
authors.lastname: Yoshimoto
authors.forename: Yunlong
authors.initials: Y
authors.lastname: Wei
mesh_terms: D016503:Drug Delivery Systems / Q000379:methods*; D017097:Electric Impedance; D005452:Fluoresceins / Q000494:pharmacology*; D005453:Fluorescence; D008081:Liposomes / Q000737:chemistry*; D012972:Sodium Hydroxide / Q000494:pharmacology; D012996:Solutions
chemical_list: D005452:Fluoresceins; D008081:Liposomes; D012996:Solutions; D012972:Sodium Hydroxide; C007740:fluorexon