title: Self-aggregated nanoparticles from methoxy poly(ethylene glycol)-modified chitosan: synthesis; characterization; aggregation and methotrexate release in vitro.
abstract: Methoxy poly(ethylene glycol)-grafted-chitosan (mPEG-g-CS) conjugates were synthesized by formaldehyde linking method and characterized by Fourier transform infrared (FT-IR) and proton nuclear magnetic resonance ((1)H-NMR). The degree of substitution (DS) of methoxy poly (ethylene glycol) (mPEG) in the mPEG-g-CS molecules determined by (1)H-NMR ranged from 19% to 42%. The critical aggregation concentration (CAC) was determined by fluorescence spectroscopy using pyrene as fluorescence probe and its value was 0.07 mg/mL in water. mPEG-g-CS formed monodisperse self-aggregated nanoparticles with a roughly spherical shape and a mean diameter of 261.9 nm were prepared by the dialysis method. mPEG-g-CS self-aggregated nanoparticles were used as carriers of poorly water-soluble anticancer drug methotrexate (MTX). MTX was physically entrapped inside mPEG-g-CS self-aggregated nanoparticles by dialysis method and the characteristics of MTX-loaded mPEG-g-CS self-aggregated nanoparticles were analyzed using dynamic laser light scattering (DLLS), transmission electron microscopy (TEM). Moreover, in vitro release behavior of MTX was also investigated and the results showed that MTX was continuously released more than 50% in 48 h.
authors.affiliation: Institute of Biomedical Engineering, Chinese Academy of Medical Sciences, Peking Union Medical College, The Key Laboratory of Biomedical Material of Tianjin, Tianjin 300192, PR China.
authors.forename: Xindu
authors.initials: X
authors.lastname: Yang
authors.forename: Qiqing
authors.initials: Q
authors.lastname: Zhang
authors.forename: Yinsong
authors.initials: Y
authors.lastname: Wang
authors.forename: Han
authors.initials: H
authors.lastname: Chen
authors.forename: Huizhu
authors.initials: H
authors.lastname: Zhang
authors.forename: Fuping
authors.initials: F
authors.lastname: Gao
authors.forename: Lingrong
authors.initials: L
authors.lastname: Liu
mesh_terms: D048271:Chitosan / Q000138:chemical synthesis; D016503:Drug Delivery Systems; D009682:Magnetic Resonance Spectroscopy; D008727:Methotrexate / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D011092:Polyethylene Glycols / Q000138:chemical synthesis* / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: C118638:glycol-chitosan; D011092:Polyethylene Glycols; C028210:monomethoxypolyethylene glycol; D048271:Chitosan; D008727:Methotrexate