22nd International Symposium on Plasma Chemistry
July 5-10, 2015; Antwerp, Belgium
Nanoparticle incorporated non-woven fabric prepared by atmospheric pressure
plasma process for antibacterial property
X. Deng1, A. Nikiforov1, D. Vujosevic2, V. Vuksanovic2 and C. Leys1
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2
Ghent University, Department of Applied Physics, Sint-Pietersnieuwstraat 41, BE-9000, Ghent, Belgium
Institute of Public Health, Center for Medical Microbiology, DzonaDzeksona bb, Podgorica, 81000, Montenegro
Abstract: A simple method for the preparation of nanoparticle incorporated non-woven
fabric with effective antibacterial property has been investigated based on atmospheric
pressure plasma process. In the work, three different nanoparticles (silver, copper and zinc
oxide nanoparticles) were employed as antibiotics. The surface chemistry and antibacterial
activity of the samples were investigated.
Keywords: nanocomposite film, antibacterial, plasma process, atmospheric pressure, XPS
1. Introduction
Non-woven materials have been used widely in
applications ranging from medical dressing to everyday
cleaning products. In recent years, a lot of attention has
been paid to achieve multifunctional performance of the
fabrics, especially in packing, health and hygiene field
[1]. Due to the potential for growth of pathogenic
microorganisms which can produce and spread diseases,
non-woven fabrics with antibacterial property are very
interesting and have been extensively studied. Usual
procedure for obtaining antibacterial textile material is
textile finishing with antibacterial agents. The molecular
antibacterials traditionally used to against bacterial face
several disadvantages, including the worldwide
emergency of antibiotic resistance, difficult to be
incorporated into many materials and sensitive to harsh
environments during many industrial processes. Inorganic
compounds in nanosize present strong antibacterial
activity at low concentration due to their high surface area
to volume ratio and unique chemical and physical
properties. Currently, the metallic nanoparticles, like
silver (Ag-NP), copper (Cu-NP) and zinc oxide (ZnONP), are thoroughly being explored and extensively
investigated as potential antibiotics, because of their
pronounced biocidal activity and much more stability
under extreme conditions [2].
Recently, we proposed a novel method for the
preparation of polyethylene terephthalate (PET) nonwoven fabrics with antibacterial properties made with
firmly immobilizing silver nanoparticles via double layer
of plasma deposited organic films. The method is based
on firmly immobilizing nanoparticles via double layer of
plasma deposited organic films. It has been confirmed
that a barrier layer can prevent the release of Ag-NPs and
control the release of silver ions.
The presented work investigates a simple way to realize
the incorporation of three different types of nanoparticles
(Ag-NP, Cu-NP, ZnO-NP). The surface chemistry of the
materials was analyzed by XPS. The antibacterial activity
of the samples was tested against Staphylococcus aureus
P-III-6-13
(S. aureus) and Escherichia coli (E. coli) as the
representatives of Gram-negative bacteria and Grampositive bacteria, respectively.
2. Experimental
Nanoparticle embedded non-woven PET fabrics were
prepared through a three step procedure. At first, an
organosilicon thin film was deposited on the surface of
the PET fabrics using a plasma jet deposition system [3].
This 70 nm layer is used as a reservation layer for the
silver immobilization and control of the silver
nanoparticles adhesion to the PET fabrics. The plasma
head is mounted on a robotic arm in order to achieve a
large scale uniform treatment.
Then, the samples with plasma deposited layer were
immersed into a suspension of nanoparticles in ethanol
and raised for drying. Silver nanoparticles (SSNANO,
USA) of 20 nm size with a purity of 99.95%, copper
nanoparticles (Sigma-Aldrich, Belgium) of 50 nm size
with a purity of 99.9%, and zinc oxide nanoparticles
(Sigma-Aldrich, Belgium) of 50 nm size with a purity of
99.7% were used throughout the experiments as
purchased. In the final step, a second layer (also called
barrier layer) of organosilicon film with a thickness of
10 nm was deposited.
3. Results and discussion
The surface element composition and chemical state of
the treated fabrics were studied by XPS and the results are
presented in Fig. 1. The value of 285 eV of the
hydrocarbon C1s core level is used as a calibration of the
energy scale.
The XPS survey spectra acquired from the control
sample and the nanoparticle incorporated samples were
presented in Fig. 1a. For the control sample which is
corresponding to the fabric treated with organosilicon
film only, it was composited of Si, O, and C. The
appearance of Ag, Cu and Zn peaks in XPS spectra for the
samples after nanoparticle incorporation reveals that the
corresponding nanoparticles have been successfully
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decorated into the materials. Figs. 1b-d display the XPS
high resolution spectra of silver, copper and zinc for those
samples with corresponding nanoparticles. In Fig. 1b,
peaks at 368.2 eV and 374.2 eV are assigned to Ag 3d 5/2
and Ag 3d 3/2 , respectively. These peaks have a splitting
of 3d doublet with 6 eV indicating the presence of
metallic silver. While, comparing to the binding energy
of Ag 3d 5/2 for bulk metal Ag at 368.2 eV, a positive
chemical shift observed for Ag 3d 5/2 (at 368.1 eV)
suggests that silver nanoparticles are partly oxidized in
the process [3]. The Cu 2p 1/2 and Cu 2p 3/2 (Figure 1(c))
centred at 952.2 eV and 932.4 eV with a spin-orbit
separation of 18.8 eV for the sample embedding Cu-NPs.
The absent of shake-up peaks at about 941.5 eV indicates
no Cu2+ are presented in the sample [4]. However, it is
difficult to identify Cu0 and Cu+ due to the limitation of
XPS resolution, as mentioned by Chen [5]. Fig. 1d
represents the XPS spectra of Zn 2p, and the peak
position of Zn 2p 1/2 and Zn 2p 3/2 locate at 1045.2 eV and
1022.2 eV respectively.
The calculated antibacterial rate against E. coli and S.
aureus are shown in Fig. 2. As one can see from the
figure, the samples incorporated the three nanoparticles
exhibits effective antibacterial activity against those two
microorganisms. Since the concentrations and the size of
incorporated nanoparticles are different, comparison on
the antibacterial efficiency among the three types of
nanoparticles will not be discussed in the contribution.
Figure 2. Efficiency of the samples with three types of
nanoparticles against E. coli and S. aureus. Each data
point and error bar represents the mean and standard
errors, respectively, of independent triplicates.
Our recent work proofs that the double layer structure
can firmly immobilize the incorporated nanoparticles
during mechanical washing cycles, which suggests the
release of the nanoparticles can be avoid in the test. Thus,
the direct interaction between nanoparticles and bacterial
membranes is negligible in the work. Then, the main
antibacterial mechanism could be expected by the
generation of active oxygen species, especially for ZnO,[6]
and the release of the bacteriostatic Ag+ and Cu2+ ions for
the non-woven fabrics incorporated with Ag-NP and
Cu-NP respectively [7, 8].
Figure 1. XPS results of the nanocomposite films: (a)
survey XPS spectra; (b) Ag3d XPS spectrum; (c) Cu2p
spectrum; (d) Zn2p spectrum.
In the antibacterial test, the non-woven fabrics coved
with organosilicon films were used as a control sample.
The test solution of 0.5 McF (~ 1.5 x 108 CFU/ml) for
each bacterium is diluted with sterile phosphate buffered
saline (PBS) to a concentration of about 106. Afterwards,
the samples were seeded with fresh E. coli and S. aureus
culture, and then were incubated at 37 ºC for 24 h. After
well vortexed, a quantity of 100 µl of homogenized
solution after incubation was spread onto three MuellerHinton (MH) agars, which were incubated 24 h at 37 ºC
for colony forming counts.
Percent reduction of
organisms R which indicates biostatic efficiency resulting
from contact with the specimen was determined using
R (%) = (B-A)/B, where A is CFU per millilitre for the
medium with the treated substrate after incubation, and B
is CFU per millilitre of the medium with the control
samples after incubation.
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4. Conclusions
Non-woven fabrics incorporated with three types of
nanoparticles, Ag-NP, Cu-NP and ZnO-NP, have been
prepared by a three step method based on atmospheric
pressure plasma process. The XPS results reveal the
nanoparticles have been successfully embedded into the
fabrics. All nanofabrics show effective antibacterial
activity against E. coli (a) and S. aureus.
5. Acknowledgements
The work was supported by STSM Grant of the COST
Action MP1101.
6. References
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9 (2001)
[2] A. Méndez-Vilas.
Science against microbial
pathogen: communicating current research and
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(Badajoz, Spain) (2011)
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X. Deng, et al. Plasma Process. Polymers, 11, 11
(2014)
Y.H. Kim, et al. J. Phys. Chem. B, 110, 49 (2006)
Z. Chen, et al. Nanotechnology, 24, 26 (2013)
O. Yamamoto. Int. J. Inorg. Mater., 3, 7 (2001)
N. Cioffi, et al. Anal. Bioanal. Chem., 381, 3 (2005)
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P-III-6-13
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