Damjana Drobne University of Ljubljana, Biotechnical Faculty

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CONFERENCE ON NANO-SAFETY 22.-24. April 2009,
Ljubljana, Slovenia
Nanosized ZnO and nano TiO2 bioavailability and
bioaccumulation
Damjana Drobne University of Ljubljana,
Biotechnical Faculty Department of Biology,
SLOVENIA E-mail Damjana.Drobne_at_bf.uni-lj.si
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• Research group for nanobiology and nanotoxicology
• Dept. Biology, Biotechnical faculty, Uni
  Ljubljana
• Damjana Drobne Vladka Leer Janez Valant iva
  Tkalec Pipan
• Marjetka Kralj Kuncic Sara Novak, student Tea
  Romih student
• ______________________________________________
• National Institute of chemstry
• Anita Jemec
• ______________________________________________
• Faculty for computer and information science, Uni
  Ljubljana
• Jernej Zupanc

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• J1-9475 (C) Elaboration and evealution of a
  single species toxicity test for nanoparticles
  with a terrestrial isopod evaluation and Izdelava
  in vrednotenje testa strupenosti (basic research
  project), Slovenian Research Agency 2006-2009

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• Aim of work
• . to study interactions between nanoparticles
  and biological systes

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In vivo and in vitro biological system
Lipid vesicles
A terrestrial isopod, a model invertebrate
organism
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Our past experiences
... studding toxicity of metal pollutants and
pesticides present in the environment.
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Present challanges
Interactions between nanoparticles and biological
systems.
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Photo M. Bele, Institute of chemistry, Ljubljana
.. .biological potential of nanosized metal oxides
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Chemicals affect target molecules or interfere
with different intracellular compartments. The
effect is propagated upwards to higher levels of
biological complexity (cells, tissue, organs,
organism) and it is manifested as toxic response.

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What about nanoparticles?
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1) One hypothesis is that nanoparticles
interact firstwith cell membrane!

A consequesnce is.
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Photo J. Valant
cells are affected, but nanoparticles were not
detected inside the cells (nanoTiO2).
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2) The other opened question is are
nanoparticle bioavailable do they
bioaccumulate?
?
By L.Ziccardi, M. McArdle, Y. Lowney, J. Tsuji

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• Do ZnO nanoparticles accumulate?

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• Our work
• model organism, terrestrial isopod P. scaber
• food exposure to nanoparticles for 4 weeks
• comparison among bioaccumulation of
• nano ZnO,
• macropowder ZnO
• ZnCl2

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• Background
• terrestrial isopods accumulate high amounts of
  meals (Zn, Pb, Cu, Fe etc). in their tissue
• a lot of knowledge already exist on the
  accumulation pattern and accumulation strategy of
  metals if offered as soluble salts

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Experimental set up
Four weeks feeding on Nanoparticel, macropowsder
or ZnCl dosed food

metal analyses in whole organism by AAS
concentrations of Zn in the body
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Background knowledge FIB/SEM,
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Photo F.Tatti, FEI
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Scanning electron micrograph of macropowder of
ZnO.
Scanning electron micrograph of nanosized ZnO
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• Results
• no diffrences in amount of accumulated Zn among
  groups

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5000 µg/g
2000 µg/g
By . Pipan Tkavec, D. Drobne, A.Jemec ,T.Romih,
P.Zidar, M.Bele
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• Discussion
• we are not able to answere the question about
  nanoaprticle bioavailability or bioaccumauation
  pottential
• the fact is that when nanosized or macrosized ZnO
  is ingetsed an equal prtion of Zn is accumulated
  as when ZnCl2 is inegested

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• Present/Future direction of research
• investigation of accumulation of other
  nanparticles with lower dissolution rates for
  example Cu and Ag nanoparticles
• Investigation of interaction between membranes
  and nanoparticles

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Photo by J.Zupanc
Computer aided analysis of lipid vesicles shape
transformations after incubation with
nanoparticles.
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• Publications
• DROBNE, Damjana, JEMEC, Anita, PIPAN, iva. In
  vivo screening to determine hazards of
  nanoparticles nanosized TiO2. Environ. pollut.
  ,2009, issue 4, vol. 157, str. 1157-1164
• JEMEC, Anita, DROBNE, Damjana, REMKAR, Maja,
  SEPCIC, Kristina, TILER, Tatjana. Effects of
  ingested nano-sized titanium dioxide on
  terrestrial isopods Porcellio scaber. Environ.
  toxicol. chem., 2008, vol. 27, no. 9, str.
  1904-1914,
• JEMEC, Anita, DROBNE, Damjana, TILER, Tatjana,
  SEPCIC, Kristina. Biochemical biomarkers in
  environmental studies-lessons learnt from enzymes
  catalase, glutathione S-transferase and
  cholinesterase in two crustacean species.
  Environ. sci. pollut. res. int., 2009, 11 str.,

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Thank you for your attention!