Synthesis Of Silver Nanoparticles With Potential Antifungical Activity
For Bamboo Treatment
Omar Pandoli
1,a*
, Fatima Ventura Pereira-Meirelles
1
,
Eric Monteiro Lobo Lobo Luz
1
, Aline Assumpção
1
,
Raquel dos Santos Martins
1
,Tommaso del Rosso
2
, Khosrow Ghavami
3,b
1
Department of Chemistry, Universidade Pontifícia Católica, Rio de Janeiro, Brazil
2
Department of Physic, Universidade Pontifícia Católica, Rio de Janeiro, Brazil
3
FZEA/USP-Pirassununga, Universidade Pontifícia Católica, Rio de Janeiro, Brazil
a
omarpandoli@puc-rio.br,
b
ghavami@puc-rio.br
Keywords: silver nanoparticle, flow chemistry, antifungal activity, bamboo
Abstract. To increase the durability of bamboo it is important to find an easy method to fill the
micro and meso structure of the biological matrix using a nano-structural material with an anti-
fungical activity. A colloidal solution of silver nanoparticle (Ag-NPs) is a dispersion of metal
nanoparticle in water with a diameter between 5-100 nm. Even if the biological mechanism is not
completly understood yet, Ag-NPs show a satisfactory bactericidal and antifungical activity. We
present a simple and rapid production of Ag-NPs made by a sol-gel synthesis in flow mode by
means of microreactor tecnology through a chemical reduction of AgNO
3
with NaBH
4
in presence
of two different organic ligands: sodium/potassium tartrate and trisodium citrate. The synthesis of
Ag-NPs in continuous flow compared to the batch technique allowed to reduce the time of
synthesis, facilitating the reproducibility of the process and consequently obtaining NPs with more
uniform physical and chemical characteristics. The microorganisms of the genus Aspergillus were
used for the microbiological tests. The effect of different Ag-NPs on microbial growth was
observed daily. In particular, it was shown that the response of the fungus is inversely proportional
to the size of the nanoparticles, cell growth is disrupt depending on the proportion between silver
and organic ligand and microbialstatic effect, especially in relation to sporulation stage was also
observed
Introduction
In the current global scenario, there has been a constant search for alternative sources of energy
in order to preserve the environment and by avoiding generating harmful waste. The introduction of
bamboo to substitute industrial materials are of great social and economic importance. Bamboo is a
plant with unique mechanical properties in terms of strength and hardness [1]. Highly resistant and
malleable, bamboo presents the high stiffness and strength-to-weight ratio compared to any wood
[2]. It is known that the mechanical properties are attributed to its fibres [3]. Specific Bamboo
species, being a fast-growing and eco-friendly natural resource is an excellent material that can be
used in different areas of engineering aiming at the use for sustainable practices. The textile
industry leverage the pulp of bamboo and turn it into cloth, and through that produce clothes in
general. In civil industry, bamboo is extremely valuable due to its low cost production, handling
and disposal and due to its fast growth rate which generates biodegradable waste. Its replacement
for steel in concrete has been considered in civil construction due to its strength. Besides its
application in furniture, objects, entertainment products like skateboards, and decorating materials.
However, the great drawback of the use of bamboo is its durability. Being an organic material, it is
also subject to several types of degradation, mainly the attack of microorganisms. Thus, the
applicability and versatility of bamboo is reduced [1].
A proposal to address this issue is to use "engineering bamboo", where the bamboo matrix is
filled with nanostructures material to improve the physical, chemical and mechanical properties.
Key Engineering Materials Submitted: 2015-05-06
ISSN: 1662-9795, Vol. 668, pp 86-91 Accepted: 2015-06-09
doi:10.4028/www.scientific.net/KEM.668.86 Online: 2015-10-13
© 2016 Trans Tech Publications, Switzerland
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