title: Self-assembled, fluorescent polymeric micelles of a graft copolymer containing carbazole for thermo-controlled drug delivery in vitro.
abstract: A novel thermosensitive amphiphilic graft copolymer PNIPAAm-g-PCbzEA appending carbazole group was successfully designed and synthesized by the free radical copolymerization of N-isopropylacrylamide with hydrophobic precursor polymers of vinyl-functionalized poly(2-(N-carbazolyl)ethyl acrylate) (PCbzEA) in DMF. The PNIPAAm-g-PCbzEA copolymer was characterized by FTIR, (1)H NMR, GPC analysis, UV-vis spectroscopy and fluorescence spectroscopy. The TEM observation shows that the graft copolymer may self-assemble into polymeric micelles exhibiting a nanospheric morphology within a narrow size range of 30-60 nm in aqueous solution. From the (1)H NMR and FTIR analysis, the polymer micelles are composed of hydrophobic PCbzEA segments as the cores and the hydrophilic PNIPAAm segements as outer shells. The resulting micelles exhibited the temperature sensitivity with a lower critical solution temperature (LCST) of 31.5 degrees C and a critical micelle concentration (CMC) of 12.9 mg/L in water. In the study of drug release, an "on-off" drug release profile was found in response to stepwise temperature changes between 20 and 40 degrees C. The cytotoxicity assays for vero cells shows good biocompatibility of the graft copolymer in vitro.
authors.affiliation: College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People's Republic of China.
authors.forename: Yunhai
authors.initials: Y
authors.lastname: Liu
authors.forename: Jibing
authors.initials: J
authors.lastname: Wu
authors.forename: Lingzhi
authors.initials: L
authors.lastname: Meng
authors.forename: Lifen
authors.initials: L
authors.lastname: Zhang
authors.forename: Xiaoju
authors.initials: X
authors.lastname: Lu
mesh_terms: D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000737:chemistry* / Q000494:pharmacology; D002227:Carbazoles / Q000737:chemistry*; D002522:Chlorocebus aethiops; D016503:Drug Delivery Systems; D005453:Fluorescence; D006358:Hot Temperature; D008727:Methotrexate / Q000737:chemistry* / Q000494:pharmacology; D008823:Micelles; D010316:Particle Size; D011109:Polymethacrylic Acids / Q000138:chemical synthesis / Q000737:chemistry*; D013057:Spectrum Analysis; D013499:Surface Properties; D013997:Time Factors; D014709:Vero Cells
chemical_list: D000964:Antimetabolites, Antineoplastic; D002227:Carbazoles; D008823:Micelles; D011109:Polymethacrylic Acids; C041514:carbazole; D008727:Methotrexate