title: Facile synthesis and characterization of water soluble ZnSe/ZnS quantum dots for cellar imaging.
abstract: Strong fluorescence and low cytotoxicity ZnSe/ZnS quantum dots (QDs) were synthesized by a facile aqueous phase route. It overcame the defects such as instability and low quantum yield of the quantum dots synthesized by early aqueous phase route. L-Glutathione (GSH) and 3-mercaptopropaonic acid (MPA) were used as mixture stabilizers to synthesize high quality ZnSe/ZnS QDs. The samples were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectrometry (XPS) and their optical properties were investigated by using UV-vis spectrophotometer, fluorescence spectrophotometer (FL), IR spectrophotometer and confocal laser scanning microscope. The synthesized ZnSe/ZnS QDs illuminated blue fluorescence under ultraviolet lamp. Its water-soluble property is excellent and the fluorescence intensity of ZnSe/ZnS QDs almost did not change after 4 months at room temperature. The average diameter of ZnSe/ZnS nanocrystals is about 3 nm and quantum yield (QY) could reach to 70.6% after repeat determination. Low cytotoxicity was ensured by investigated SCG7901 and RAW264.7 cells. In comparison with cadmium based nanocrystals, ZnSe/ZnS QDs posed low cytotoxicity. The cells viability remained 96.7% when the QDs concentration was increased to 10 μmol/L. The results in vitro indicate that ZnSe/ZnS QDs-based probes have good stability, low toxicity and biocompatibility for fluorescence imaging in cancer model system.
authors.affiliation: Department of Analytical Chemistry, China Pharmaceutical University, NanJing 210009, PR China.
authors.forename: Chang
authors.initials: C
authors.lastname: Shu
authors.forename: Bin
authors.initials: B
authors.lastname: Huang
authors.forename: Xiangdong
authors.initials: X
authors.lastname: Chen
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Xuequan
authors.initials: X
authors.lastname: Li
authors.forename: Li
authors.initials: L
authors.lastname: Ding
authors.forename: Wenying
authors.initials: W
authors.lastname: Zhong
mesh_terms: D000042:Absorption; D000818:Animals; D016923:Cell Death / Q000187:drug effects; D002460:Cell Line; D045744:Cell Line, Tumor; D006801:Humans; D051379:Mice; D046529:Microscopy, Electron, Transmission; D057054:Molecular Imaging / Q000379:methods*; D056951:Photoelectron Spectroscopy; D045663:Quantum Dots; D018036:Selenium Compounds / Q000138:chemical synthesis* / Q000737:chemistry / Q000633:toxicity; D012995:Solubility; D013050:Spectrometry, Fluorescence; D017550:Spectroscopy, Fourier Transform Infrared; D013440:Sulfides / Q000138:chemical synthesis* / Q000737:chemistry / Q000633:toxicity; D013499:Surface Properties; D014867:Water / Q000737:chemistry*; D014961:X-Ray Diffraction; D017967:Zinc Compounds / Q000138:chemical synthesis* / Q000737:chemistry / Q000633:toxicity
chemical_list: D018036:Selenium Compounds; D013440:Sulfides; D017967:Zinc Compounds; D014867:Water; C031238:zinc sulfide; C044696:zinc selenide