New Nanoparticles Findings from University of Iowa Reported (Uptake, Translocation, and Transformation of Quantum Dots with Cationic versus Anionic Coatings by Populus deltoides x nigra Cuttings)
By a News Reporter-Staff News Editor at Physics Week -- Investigators publish new report on Nanoparticles. According to news reporting out of Iowa City, Iowa, by VerticalNews editors, research stated, "Manipulation of the organic coatings of nanoparticles such as quantum dots (QDs) to enhance specific applications may also affect their interaction and uptake by different organisms. In this study, poplar trees (Populus deltoides x nigra) were exposed hydroponically to 50-nM CdSe/CdZnS QDs coated with cationic polyethylenimine (PEI) (35.3 +/- 6.6 nm) or poly(ethylene glycol) of anionic poly(acrylic acid) (PAA-EG) (19.5 +/- 7.2 nm) to discern how coating charge affects nanoparticle uptake, translocation, and transformation within woody plants."
Our news journalists obtained a quote from the research from the University of Iowa, "Uptake of cationic PEI-QDs was 10 times faster despite their larger hydrodynamic size and higher extent of aggregation (17 times larger than PAA-EG-QDs after 11-day incubation in the hydroponic medium), possibly due to electrostatic attraction to the negatively charged root cell wall. QDs cores aggregated upon root uptake, and their translocation to poplar shoots (negligible for PAA-EG-QDs and 0.7 ng Cd/mg stem for PEI-QDs) was likely limited by the endodermis. After 2-day exposure, PEI and PAA-EG coatings were likely degraded from the internalized QDs inside the plant, leading to the aggregation of the metallic cores and a 'red-shift' of fluorescence. The fluorescence of PEI-QD aggregates was stable inside the roots through the 11-day exposure period. In contrast, the PAA-EG-QD aggregates lost fluorescence inside the plant after 11 days probably due to destabilization of the coating, even though these QDs were stable in the hydroponic solution."
According to the news editors, the research concluded: "Overall, these results highlight the importance of coating properties in the rate and extent to which nanoparticles are assimilated by plants and potentially introduced into food webs."
For more information on this research see: Uptake, Translocation, and Transformation of Quantum Dots with Cationic versus Anionic Coatings by Populus deltoides x nigra Cuttings. Environmental Science & Technology, 2014;48(12):6754-6762. Environmental Science & Technology can be contacted at: Amer Chemical Soc, 1155 16TH St, NW, Washington, DC 20036, USA. (American Chemical Society - www.acs.org; Environmental Science & Technology - www.pubs.acs.org/journal/esthag)
Our news journalists report that additional information may be obtained by contacting J. Wang, University of Iowa, Dept. of Civil & Environm Engn, Iowa City, IA 52242, United States. Additional authors for this research include Y. Yang, H.G. Zhu, J. Braam, J.L. Schnoor and P.J.J. Alvarez.
Keywords for this news article include: Iowa City, Quantum Dots, United States, Nanotechnology, Quantum Physics, Emerging Technologies, North and Central America
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