title: Enhancement of cell internalization and photostability of red and green emitter quantum dots upon entrapment in novel cationic nanoliposomes.
abstract: Two quantum dots (QDs), a green emitter, CdSe and a red emitter, CdSe with ZnS shell are encapsulated into novel liposomes in two different formulations including cationic liposomes. Quantum dots have proven themselves as powerful inorganic fluorescent probes, especially for long-term, multiplexed imaging and detection. Upon delivery into a cell, in endocytic vesicles such as endosomes, their fluorescence is quenched. We have investigated the potential toxic effects, photophysical properties and cell internalization of QDs in new formulation of liposomes as an in vitro vesicle model. Entrapment of QDs into liposomes is brought about with a decrease in their intrinsic fluorescence and toxicities and an increase in their photostability and lifetime. The biomimetic lipid bilayer of liposomes provides high biocompatibility, thereby enhancing the effectiveness of fluorescent nanoparticles for biological recognition in vitro and in vivo. The prepared lipodots could effectively prevent QDs from photo-oxidation during storage and when exposed to ultraviolet (UV) light. Moreover, the flow cytometry of HEK 293 T cells showed that the cell internalization of encapsulated QDs in (DSPC/CHO/DOPE/DOAB) liposome is enhanced 10 times compared with non-encapsulated QD (bare QDs).
authors: Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
authors: Hamid Reza
authors: HR
authors: Samadikhah
authors: Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
authors: Maryam
authors: M
authors: Nikkhah
authors: Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
authors: Saman
authors: S
authors: Hosseinkhani
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry*; D002470:Cell Survival / Q000187:drug effects; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000737:chemistry / Q000493:pharmacokinetics; D057809:HEK293 Cells; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008051:Lipid Bilayers / Q000737:chemistry; D008081:Liposomes / Q000737:chemistry* / Q000493:pharmacokinetics*; D046529:Microscopy, Electron, Transmission; D008856:Microscopy, Fluorescence; D053758:Nanoparticles / Q000737:chemistry; D010316:Particle Size; D045663:Quantum Dots / Q000737:chemistry* / Q000378:metabolism; D018036:Selenium Compounds / Q000737:chemistry*; D014466:Ultraviolet Rays; D017967:Zinc Compounds / Q000737:chemistry*
chemical_list: D019187:Cadmium Compounds; D005456:Fluorescent Dyes; D008051:Lipid Bilayers; D008081:Liposomes; D018036:Selenium Compounds; D017967:Zinc Compounds; C058667:cadmium selenide; C044696:zinc selenide
keywords: biocompatibility; liposome; photo-oxidation; photoustability; quantum dots