title: Ultrasmall Magnetically Engineered Ag2Se Quantum Dots for Instant Efficient Labeling and Whole-Body High-Resolution Multimodal Real-Time Tracking of Cell-Derived Microvesicles.
abstract: Cell-derived microvesicles (MVs) are natural carriers that can transport biological molecules between cells, which are expected to be promising delivery vehicles for therapeutic purposes. Strategies to label MVs are very important for investigation and application of MVs. Herein, ultrasmall Mn-magnetofunctionalized Ag2Se quantum dots (Ag2Se@Mn QDs) integrated with excellent near-infrared (NIR) fluorescence and magnetic resonance (MR) imaging capabilities have been developed for instant efficient labeling of MVs for their in vivo high-resolution dual-mode tracking. The Ag2Se@Mn QDs were fabricated by controlling the reaction of Mn(2+) with the Ag2Se nanocrystals having been pretreated in 80 °C NaOH solution, with an ultrasmall size of ca. 1.8 nm, water dispersibility, high NIR fluorescence quantum yield of 13.2%, and high longitudinal relaxivity of 12.87 mM(-1) s(-1) (almost four times that of the commercial contrast agent Gd-DTPA). The ultrasmall size of the Ag2Se@Mn QDs enables them to be directly and efficiently loaded into MVs by electroporation, instantly and reliably conferring both NIR fluorescence and MR traceability on MVs. Our method for labeling MVs of different origins is universal and free of unfavorable influence on intrinsic behaviors of MVs. The complementary imaging capabilities of the Ag2Se@Mn QDs have made the long-term noninvasive whole-body high-resolution dual-mode tracking of MVs in vivo realized, by which the dynamic biodistribution of MVs has been revealed in a real-time and in situ quantitative manner. This work not only opens a new window for labeling with QDs, but also facilitates greatly the investigation and application of MVs.
authors.affiliation: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, State Key Laboratory of Virology, The Institute for Advanced Studies, and Wuhan Institute of Biotechnology, Wuhan University , Wuhan, 430072, P. R. China.
authors.forename: Jing-Ya
authors.initials: JY
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, State Key Laboratory of Virology, The Institute for Advanced Studies, and Wuhan Institute of Biotechnology, Wuhan University , Wuhan, 430072, P. R. China.|Key Laboratory of Oral Biomedicine (Ministry of Education) and Department of Oral and Maxillofacial Surgery, School and Hospital of Stomatology, Wuhan University , Wuhan, 430079, P. R. China.
authors.forename: Gang
authors.initials: G
authors.lastname: Chen
authors.affiliation: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, State Key Laboratory of Virology, The Institute for Advanced Studies, and Wuhan Institute of Biotechnology, Wuhan University , Wuhan, 430072, P. R. China.
authors.forename: Yi-Ping
authors.initials: YP
authors.lastname: Gu
authors.affiliation: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, State Key Laboratory of Virology, The Institute for Advanced Studies, and Wuhan Institute of Biotechnology, Wuhan University , Wuhan, 430072, P. R. China.
authors.forename: Ran
authors.initials: R
authors.lastname: Cui
authors.affiliation: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, State Key Laboratory of Virology, The Institute for Advanced Studies, and Wuhan Institute of Biotechnology, Wuhan University , Wuhan, 430072, P. R. China.
authors.forename: Zhi-Ling
authors.initials: ZL
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Oral Biomedicine (Ministry of Education) and Department of Oral and Maxillofacial Surgery, School and Hospital of Stomatology, Wuhan University , Wuhan, 430079, P. R. China.
authors.forename: Zi-Li
authors.initials: ZL
authors.lastname: Yu
authors.affiliation: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, State Key Laboratory of Virology, The Institute for Advanced Studies, and Wuhan Institute of Biotechnology, Wuhan University , Wuhan, 430072, P. R. China.
authors.forename: Bo
authors.initials: B
authors.lastname: Tang
authors.affiliation: Key Laboratory of Oral Biomedicine (Ministry of Education) and Department of Oral and Maxillofacial Surgery, School and Hospital of Stomatology, Wuhan University , Wuhan, 430079, P. R. China.
authors.forename: Yi-Fang
authors.initials: YF
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, State Key Laboratory of Virology, The Institute for Advanced Studies, and Wuhan Institute of Biotechnology, Wuhan University , Wuhan, 430072, P. R. China.
authors.forename: Dai-Wen
authors.initials: DW
authors.lastname: Pang
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D045744:Cell Line, Tumor; D006801:Humans; D008280:Magnetics; D051379:Mice; D045663:Quantum Dots; D012834:Silver / Q000737:chemistry*; D013057:Spectrum Analysis / Q000379:methods
chemical_list: D001672:Biocompatible Materials; D012834:Silver