title: High efficiency transport of quantum dots into plant roots with the aid of silwet L-77.
abstract: Quantum dots (QDs) are a novel type of small, photostable and bright fluorophores that have been successfully applied to mammalian and human live cell imaging. In this study, highly dispersive water-soluble mercaptoacetic acid (MAA)-coated CdSe/ZnS QDs were synthesized, which were suitable for investigation as fluorescent probe labels. The treatment of maize seedling roots with QDs showed that the surfactant silwet L-77 aided the efficient transport of QDs into maize roots. Under a concentration ranging from 0.128 to 1.28 microM, QDs caused very low cytotoxicity on maize seed germination and root growth. The addition of mercuric chloride to the Hoagland solution resulted in a decrease of QD content in root tissues, and this decrease was reversed upon the addition of beta-mercaptoethanol, which suggests that mercury-sensitive processes play a significant role in regulating QD flow in the maize root system. We speculate that the apoplastic pathway can contribute substantially to the total quantity of QDs reaching the stele. Therefore, based on this transport approach, MAA-coated QDs can be utilized for live imaging in plant systems to verify known physiological processes.
authors.affiliation: Key Laboratory of MOE for Plant Development Biology, College of Life Sciences, Wuhan University, Wuhan 430072, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Hu
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Lu
authors.initials: L
authors.lastname: Ma
authors.forename: Qionglin
authors.initials: Q
authors.lastname: Peng
authors.forename: Wei
authors.initials: W
authors.lastname: Feng
authors.forename: Lu
authors.initials: L
authors.lastname: Zhang
authors.forename: Shibin
authors.initials: S
authors.lastname: He
authors.forename: Fei
authors.initials: F
authors.lastname: Yang
authors.forename: Jing
authors.initials: J
authors.lastname: Huang
authors.forename: Lijia
authors.initials: L
authors.lastname: Li
mesh_terms: D001692:Biological Transport / Q000187:drug effects; D005453:Fluorescence; D008163:Luminescent Measurements / Q000295:instrumentation / Q000379:methods; D008623:Mercaptoethanol / Q000737:chemistry / Q000494:pharmacology; D008627:Mercuric Chloride / Q000737:chemistry / Q000494:pharmacology; D008856:Microscopy, Fluorescence; D017646:Organosilicon Compounds / Q000737:chemistry / Q000494:pharmacology*; D018517:Plant Roots / Q000737:chemistry / Q000378:metabolism*; D045663:Quantum Dots; D013864:Thioglycolates / Q000737:chemistry / Q000494:pharmacology; D003313:Zea mays / Q000737:chemistry / Q000378:metabolism*
chemical_list: D017646:Organosilicon Compounds; D013864:Thioglycolates; C473569:silwet L-77; D008627:Mercuric Chloride; D008623:Mercaptoethanol; C017487:2-mercaptoacetate