title: Nanoemulsion-templated polylelectrolyte multifunctional nanocapsules for DNA entrapment and bioimaging.
abstract: The emerging field of bionanotechnology aims at advancing colloidal and biomedical research via introduction of multifunctional nanoparticle-based containers intended for both gene therapy and bioimaging. In the present contribution we entrapped the model genetic material (herring testes DNA) in the newly-designed non-viral vectors, i.e., multifunctional nanocapsules obtained by layer-by-layer (LbL) adsorption of DNA and oppositely charged polysaccharide-based chitosan (CHIT) on the nanoemulsion core, loaded by IR-780 indocyanine (used as the fluorescent marker) and stabilized by gemini-type ammonium salts: N,N,N',N'-tetramethyl-N,N'-di(dodecyl)-ethylenediammonium bromide, d(DDA)PBr and N,N,N',N'-tetramethyl-N,N'-di(dodecyl)-butylenediammonium d(DDA)BBr. Ternary phase diagrams of the surfactant-oil-water systems were determined by titration method. Then, the stability of the nanoemulsions obtained with IR-780 solubilized in the oleic acid (OA) or isopropyl myristate (IPM) phase was evaluated by backscattering (BS) profiles and ζ-potential measurements. In the next step, CHIT and DNA layers were subsequently deposited on the kinetically stable nanoemulsion cores. The IR-780-loaded nanocarriers covered by (DNA/CHIT)4 bilayers shown the high ζ-potential value (about +43mV provided by Doppler electrophoresis), the size <120nm and the spherical shape as analyzed by dynamic light scattering (DLS), atomic force microscopy (AFM) and scanning electron microscopy (SEM). Finally, the long-lasting nanosystems were subjected to in vitro biological studies on human cancer cell lines - doxorubicin-sensitive breast (MCF-7/WT), epithelial lung adenocarcinoma (A549) and skin melanoma (MEWO). Biological response of the cell culture was expressed as cytotoxic activity evaluated by MTT-based proliferation assay as well as bioimaging of intracellular localization of IR-780 molecules loaded in the multilayer DNA-deposited nanocontainers - provided by confocal laser scanning microscopy (CLSM) and total internal reflection fluorescence microscopy (TIRFM). Our results demonstrate that the fabricated oil-core CHIT-coated nanocapsules stabilized by both d(DDA)PBr and d(DDA)BBr surfactants are promising as multifunctional nanocarriers for DNA delivery and cancer diagnostics.
authors.affiliation: Department of Organic and Pharmaceutical Technology, Faculty of Chemistry, Wrocław University of Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland. Electronic address: urszula.bazylinska@pwr.edu.pl.
authors.forename: Urszula
authors.initials: U
authors.lastname: Bazylińska
authors.affiliation: Department of Medical Biochemistry, Medical University of Wroclaw, Chałubinskiego 10, 50-368 Wroclaw, Poland.
authors.forename: Jolanta
authors.initials: J
authors.lastname: Saczko
mesh_terms: D045744:Cell Line, Tumor; D004247:DNA / Q000737:chemistry*; D004573:Electrolytes / Q000737:chemistry*; D004655:Emulsions; D006801:Humans; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D053769:Nanocapsules; D013056:Spectrophotometry, Ultraviolet; D013501:Surface-Active Agents / Q000737:chemistry
chemical_list: D004573:Electrolytes; D004655:Emulsions; D053769:Nanocapsules; D013501:Surface-Active Agents; D004247:DNA
keywords: Cationic gemini-type surfactants; Chitosan; Human cancer cell lines; IR-780 cyanine; Layer-by-layer approach; Oil-core nanocarriers