title: Blood Clearance, Distribution, Transformation, Excretion, and Toxicity of Near-Infrared Quantum Dots Ag2Se in Mice.
abstract: As a novel fluorescent probe in the second near-infrared window, Ag2Se quantum dots (QDs) exhibit great prospect in in vivo imaging due to their maximal penetration depth and negligible background. However, the in vivo behavior and toxicity of Ag2Se QDs still largely remain unknown, which severely hinders their wide-ranging biomedical applications. Herein, we systematically studied the blood clearance, distribution, transformation, excretion, and toxicity of polyethylene glycol (PEG) coated Ag2Se QDs in mice after intravenous administration with a high dose of 8 μmol/kg body weight. QDs are quickly cleared from the blood with a circulation half-life of 0.4 h. QDs mainly accumulate in liver and spleen and are remarkably transformed into Ag and Se within 1 week. Ag is excreted from the body readily through both feces and urine, whereas Se is excreted hardly. The toxicological evaluations demonstrate that there is no overt acute toxicity of Ag2Se QDs to mice. Moreover, in regard to the in vivo stability problem of Ag2Se QDs, the biotransformation and its related metabolism are intensively discussed, and some promising coating means for Ag2Se QDs to avert transformation are proposed as well. Our work lays a solid foundation for safe applications of Ag2Se QDs in bioimaging in the future.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Tang
authors.affiliation: College of Chemistry and Environment Protection Engineering, Southwest University for Nationalities , Chengdu 610041, China.
authors.forename: Sheng-Tao
authors.initials: ST
authors.lastname: Yang
authors.affiliation: Institute of Nanochemistry and Nanobiology, Shanghai University , Shanghai 200444, China.
authors.forename: Yi-Fan
authors.initials: YF
authors.lastname: Yang
authors.affiliation: Institute of Nanochemistry and Nanobiology, Shanghai University , Shanghai 200444, China.
authors.forename: Da-Ming
authors.initials: DM
authors.lastname: Ke
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, China.
authors.forename: Jia-Hui
authors.initials: JH
authors.lastname: Liu
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Chen
authors.affiliation: Institute of Nanochemistry and Nanobiology, Shanghai University , Shanghai 200444, China.
authors.forename: Haifang
authors.initials: H
authors.lastname: Wang
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, China.|Institute of Nanochemistry and Nanobiology, Shanghai University , Shanghai 200444, China.
authors.forename: Yuanfang
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000818:Animals; D005456:Fluorescent Dyes / Q000737:chemistry / Q000493:pharmacokinetics / Q000633:toxicity; D007259:Infrared Rays; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D008819:Mice, Nude; D011092:Polyethylene Glycols / Q000737:chemistry / Q000493:pharmacokinetics / Q000633:toxicity; D045663:Quantum Dots / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity*; D011897:Random Allocation; D018036:Selenium Compounds / Q000097:blood / Q000737:chemistry / Q000493:pharmacokinetics* / Q000633:toxicity*; D018030:Silver Compounds / Q000097:blood / Q000737:chemistry / Q000493:pharmacokinetics* / Q000633:toxicity*; D014018:Tissue Distribution
chemical_list: D005456:Fluorescent Dyes; D018036:Selenium Compounds; D018030:Silver Compounds; D011092:Polyethylene Glycols
keywords: Ag2Se; biodistribution; biotransformation; blood clearance; quantum dots; toxicity