title: Soft-binding ligand-capped fluorescent CdSe/ZnS quantum dots for the facile labeling of polysaccharide-based self-assemblies.
abstract: In this research, soft-binding aminopropanol (APP) was employed as an efficient ligand, for the transfer of as-prepared hydrophobic CdSe/ZnS quantum dots (QDs) into polar solvents. It was found that the ligands at the surface of the original QDs could be completely replaced by APP after a phase-transferring process which successfully maintained fluorescence properties and original morphology of the QDs. The resulting intermediate QDs were soluble in common polar organic solvents, such as dimethyl sulfoxide (DMSO), dimethyl formamide (DMF) and tetrahydrofuran (THF), and the soft-binding ligand could be easily removed by exposure to water. Taking advantage of the excellent solubility of the APP-capped QDs and the soft-binding characteristics of APP, a novel reaction-free method was investigated for the fluorescent labeling of polysaccharide-based micelles via encapsulation of the intermediate QDs. The incorporation of QDs had little effect on the size of the micelles and did not elevate their cytotoxicity. A photo-induced fluorescence enhancement effect was observed for the incorporated QDs, and the QD-labeled micelles could be used for cell imaging. The concept of soft-binding ligand capped QDs and the reaction-free fluorescent labeling method can be applied to a wide range of QD studies.
authors: MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, People's Republic of China.
authors: Moyuan
authors: M
authors: Cao
authors: Lin
authors: L
authors: Yu
authors: Ping
authors: P
authors: Zhang
authors: Han
authors: H
authors: Xiong
authors: Yucun
authors: Y
authors: Jin
authors: Yi
authors: Y
authors: Lu
authors: Li-Qun
authors: LQ
authors: Wang
mesh_terms: D001665:Binding Sites; D019187:Cadmium Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D005453:Fluorescence; D008024:Ligands; D008958:Models, Molecular; D010316:Particle Size; D011134:Polysaccharides / Q000138:chemical synthesis* / Q000737:chemistry; D045663:Quantum Dots; D018036:Selenium Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D013194:Staining and Labeling; D013440:Sulfides / Q000138:chemical synthesis / Q000737:chemistry*; D013499:Surface Properties; D017967:Zinc Compounds / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D019187:Cadmium Compounds; D008024:Ligands; D011134:Polysaccharides; D018036:Selenium Compounds; D013440:Sulfides; D017967:Zinc Compounds; C058667:cadmium selenide; C031238:zinc sulfide