title: Cucurbit[8]uril supramolecular assembly for positively charged ultrathin films as nanocontainers.
abstract: The design of positively charged ultrathin films for surface modification is of crucial importance for biomedical applications. Herein, we report the layer-by-layer assembly of pure positively charged ultrathin films based on the host-guest interaction of cucurbit[8]uril (CB[8]). Two positively charged poly(ethylenimine)s (PEI) functionalized with guest moieties methyl viologen (MV) and indole (ID) were alternately assembled with the formation of CB[8] ternary complex under basic conditions. The growth of the (PEI-MV@CB[8]/PEI-ID) films was monitored by spectroscopic ellipsometry and quartz crystal microbalance. The morphology and structure of the films were characterized by scanning electron microscopy and UV-vis spectroscopy, respectively. These positively charged (PEI-MV@CB[8]/PEI-ID) films were very stable in the pH range from 4 to 9 but disassembled immediately when subjected to a competitive guest adamantylamine. Finally, the films were successfully employed as nanocontainers for DNA loading and subsequent directing the transfection of the adhered cells.
authors.affiliation: MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University , Hangzhou, China.
authors.forename: Dan-dan
authors.initials: DD
authors.lastname: Li
authors.forename: Ke-feng
authors.initials: KF
authors.lastname: Ren
authors.forename: Hao
authors.initials: H
authors.lastname: Chang
authors.forename: Hai-bo
authors.initials: HB
authors.lastname: Wang
authors.forename: Jin-lei
authors.initials: JL
authors.lastname: Wang
authors.forename: Chao-jian
authors.initials: CJ
authors.lastname: Chen
authors.forename: Jian
authors.initials: J
authors.lastname: Ji
mesh_terms: D001952:Bridged-Ring Compounds / Q000737:chemistry*; D004247:DNA / Q000737:chemistry / Q000235:genetics; D004337:Drug Carriers / Q000737:chemistry*; D007093:Imidazoles / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry; D049329:Nanostructures / Q000737:chemistry*; D010269:Paraquat / Q000737:chemistry; D011094:Polyethyleneimine / Q000737:chemistry; D013499:Surface Properties; D014162:Transfection; D047028:Macrocyclic Compounds; D000099246:Cucurbit(n)urils
chemical_list: D001952:Bridged-Ring Compounds; D004247:DNA; D004337:Drug Carriers; D007093:Imidazoles; D007211:Indoles; D010269:Paraquat; D011094:Polyethyleneimine; C507198:cucurbit(8)uril; D047028:Macrocyclic Compounds; D000099246:Cucurbit(n)urils; C030374:indole