@Article{MontanheiroMFMTPML:2018:CyPhEv,
author = "Montanheiro, Thais L. A. and Montagna, Larissa S. and Farias,
Marcelo A. de and Magalh{\~a}es, J{\'e}ssica A. and Tada, Dayane
B. and Passador, F{\'a}bio R. and Machado, Jo{\~a}o Paulo Barros
and Lemes, Ana Paula",
affiliation = "{Universidade de S{\~a}o Paulo (USP)} and {Universidade de
S{\~a}o Paulo (USP)} and {Laborat{\'o}rio Naiconal de
Nanotecnologia} and {Universidade de S{\~a}o Paulo (USP)} and
{Universidade de S{\~a}o Paulo (USP)} and {Universidade de
S{\~a}o Paulo (USP)} and {Instituto Nacional de Pesquisas
Espaciais (INPE)} and {Universidade de S{\~a}o Paulo (USP)}",
title = "Cytotoxicity and physico-chemical evaluation of acetylated and
pegylated cellulose nanocrystals",
journal = "Journal of Nanoparticle Research",
year = "2018",
volume = "20",
number = "8",
pages = "e206",
month = "Aug.",
keywords = "Cellulose nanocrystal . Acetylation . Pegylation . Nanoparticle .
Functionalization . Hydrophilicity. Cell proliferation.",
abstract = "The high hydrophilicity of cellulose nanocrystals (CNC) may result
in poor dispersion in some matrices and solvents. So in this work,
two different methodologies were used to reduce the hydrophilicity
of CNC. In the first methodology, CNC were acetylated (CNC-Ac) in
a mixture of acetic and hydrochloric acid, and in the second
methodology, polyethylene glycol (PEG) was adsorbed onto CNC
surface (CNC-PEG) under stirring in aqueous solution. CNC obtained
by both methods were characterized by transmission electron
microscopy (TEM), infrared spectroscopy (FTIR), X-ray diffraction
(XRD), dynamic light scattering (DLS), zeta potential, and
thermogravimetric analysis (TGA). Images of TEM showed that the
intrinsic morphology of cellulose was preserved after both
treatments. FTIR confirmed acetylation reaction by the presence of
a new band at 1732 cm\−1 (acetate groups) and the
consumption of OH groups. XRD showed a reduction in the
crystallinity index for both applied methodologies. DLS showed
reduced stability in water for CNC-Ac and CNC-PEG. Values of zeta
potential changed after acetylation, from \− 45 mV (CNC) to
\− 1 mV (CNC-Ac), and after adsorption of PEG, to \−
26.7 mV (CNC-PEG). TGA showed a reduction in the thermal stability
after both treatments and a change in the main degradation
behavior for CNC-PEG. MTT assays showed that both proposed
functionalizations induce cell proliferation, being even more
evident for acetylation because, in addition to viability increase
with time, it increased with the sample concentration.",
doi = "10.1007/s11051-018-4306-3",
url = "http://dx.doi.org/10.1007/s11051-018-4306-3",
issn = "1388-0764",
language = "en",
targetfile = "montanheiro_cytotoxicity.pdf",
urlaccessdate = "27 abr. 2024"
}