title: Insight into glycyrrhetinic acid: the role of the hydroxyl group on liver targeting.
abstract: Two kinds of glycyrrhetinic acid-modified chitosan/poly(ethylene glycol) nanoparticles (CTS/PEG-GA NPs) were prepared by an ionic gelation process in which the liver targeting ligand glycyrrhetinic acid (GA) was introduced into the nanoparticles at the C(30)-carboxyl group (CTS/PEG-GA(c) NPs) or the C(3)-hydroxyl group (CTS/PEG-GA(h) NPs). Their characteristics, especially their ability to target the liver, were compared. The results showed that both the CTS/PEG-GA(c) NPs and the CTS/PEG-GA(h) NPs are remarkably targeted to the liver. The accumulation in the liver is 51.3% and 56.5% of the injected dose for the CTS/PEG-GA(c)(4.60%) NPs (the subscript number denotes the GA content as weight percent in nanoparticles) and the CTS/PEG-GA(h)(4.57%) NPs at 3 h after injection, respectively. This is nearly 2.6-2.8 times higher than that obtained with the CTS/PEG NPs. According to our results, there is no significant difference between the CTS/PEG-GA(c) NPs and the CTS/PEG-GA(h) NPs in their ability to target the liver, when they were formed under identical conditions. This indicated that the C(3)-hydroxyl group in GA has little influence on the targeting ability.
authors.affiliation: Key Laboratory of Functional Polymer Materials, Ministry of Education, Institute of Polymer Chemistry, Nankai University, Tianjin 300071, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Tian
authors.forename: Xiuhua
authors.initials: X
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Chuangnian
authors.initials: C
authors.lastname: Zhang
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liu
authors.forename: Zhi
authors.initials: Z
authors.lastname: Yuan
mesh_terms: D000818:Animals; D048271:Chitosan / Q000737:chemistry* / Q000493:pharmacokinetics; D004337:Drug Carriers / Q000008:administration & dosage / Q000737:chemistry* / Q000493:pharmacokinetics; D006034:Glycyrrhetinic Acid / Q000737:chemistry* / Q000493:pharmacokinetics; D008099:Liver / Q000378:metabolism*; D051379:Mice; D053758:Nanoparticles; D011092:Polyethylene Glycols / Q000737:chemistry* / Q000493:pharmacokinetics; D013499:Surface Properties
chemical_list: D004337:Drug Carriers; D011092:Polyethylene Glycols; D048271:Chitosan; D006034:Glycyrrhetinic Acid