LNNano - Brazilian Nanotechnology National Laboratory

Magneto-luminescent nanoplatform – Low toxicity and uptake in Zebrafish embryos

Fe3O4@SiO2 Nanoparticles Concurrently Coated with Chitosan and GdOF:Ce3+,Tb3+Luminophore for Bioimaging: Toxicity Evaluation in the Zebrafish Model

Latif U. Khana*, Gabriela H. Silvaa,b, Aline M. Z. de Medeirosa,b, Zahid U. Khanc, Magnus Gidlundc, Hermi F. Britod, Oscar Moscoso-Londoñoe,f, Diego Muracae, Marcelo Knobele, Carlos A. Pérezg* and Diego Stéfani T. Martineza,b*

aBrazilian Nanotechnology National Laboratory (LNNano), Brazilian Center for Research in Energy and Materials (CNPEM), Zip Code 13084-970, Campinas-SP, Brazil.

bCentre for Nuclear Energy in Agriculture (CENA), University of São Paulo (USP), Zip Code 13416-000, Piracicaba-SP, Brazil.

cDepartment of Immunology, Institute of Biomedical Sciences-IV, University of Sao Paulo (USP), Zip Code 05508-000, São Paulo-SP, Brazil.

dDepartment of Fundamental Chemistry, Institute of Chemistry, University of Sao Paulo (USP), Zip Code 05508-000, São Paulo-SP, Brazil.

 eInstitute of Physics “Gleb Wataghin”, University of Campinas (UNICAMP), Zip Code 13083859, Campinas-SP, Brazil.

fFaculty of Engineering, Autonomous University of Manizales, Antigua Estación del Ferrocarril, Manizales, Colombia.

gBrazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials (CNPEM), Zip Code 13084-970, Campinas-SP, Brazil.

Abstract

In this work, design and physiochemical characterization of a biocompatible nanoplatform with integrated photoluminescence and magnetic properties were reported. The potential in vivo toxicity was assessed by exploring the biodistribution of nanoparticles using synchrotron X-ray fluorescence (SXRF) imaging in the zebrafish embryos as a biological model. Their synthesis is accessible through combining magnetic iron oxide nanoparticles with Ce3+– and Tb3+-doped GdOF luminophore and concurrent capping in situ with chitosan biopolymer. The Fe3O4@SiO2/GdOF:xCe3+,yTb3+ nanoparticles manifested near superparamagnetic behavior at 300 K, displaying green emission lines, arising from the characteristic 5D4 → 7FJ transitions (J = 6–0) of Tb3+ ion. The limited permeability of the chorion membrane is a critical factor in toxicity screening, a potential approach to remove the chorion and expose the chorion-off zebrafish embryos to nanoscale materials. Accordingly, multifunctional nanoparticles exhibited no acute toxicity to the with-chorion and chorion-off zebrafish embryos up to 100 mg L–1 exposure concentration, suggesting remarkable in vivo biocompatibility. By assessing the nanobio interaction via deep-tissue SXRF imaging, it was visualized that the distribution of Gd and Fe elements had occurred with a roughly constant relative ratio in the whole body of early-stage embryos. However, the elements mapping data revealed a predominant localization of Gd and Fe in the gastrointestinal tract, manifesting bioaccumulation of magneto-luminescent nanoparticles as an integrated nanoplatform in the respective region. This result demonstrated that the particles’ uptake by embryos were mostly through oral exposure rather than the dermal pathway, offering a new route to oral administration of nanoparticles for future biological and environmental applications.

ACS Applied Nano Materials

Link: https://pubs.acs.org/doi/full/10.1021/acsanm.9b00339

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Link: https://pubs.acs.org/toc/aanmf6/2/6