Eco-friendly Surface Modification …
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and strong antimicrobial effects in its ionic state (Ag
+ ) (Deng et al. 2015). Zinc oxide
(ZnO) nanoparticles possess excellent photocatalytic activity, superior UV blocking
capacity, as well as antifungal and antibacterial properties (Rezaei 2016). ZnO is an
inexpensive and abundant material. The use of nanoparticles has been done extensively to enhance the antimicrobial activity of textile materials as their size is similar
to that of most biological molecules. Therefore, they can easily penetrate the organic
matrix and can be used for in vivo and in vitro medical research. Metallic oxides or
metals in ionic states are toxic to bacteria even at low concentrations. The various
mechanisms responsible for the action have been proposed. Binding to intracellular
proteins and inactivating the bacteria or damage to microbial cell wall due to reactive oxygen species are some of the reported effects of metal nanoparticles (Shahidi
2018). However, their immobilisation on textile material is a challenge which can
be overcome by pretreatment of fabric by plasma, and many studies have reported
favourable results (Airoudj et al. 2014).
Cellulose is the most prevalent natural biopolymer on this planet, assimilating
many important properties like bioavailability, biodegradability and biocompatibility.
Cotton is the natural fibre which is composed of 95% cellulose. It is the primary source
of sustainable clothing material with the highest demand due to being comfortable
to wear and easy to maintain. Natural cellulose materials are easily attacked by
microbes like bacteria and fungi due to their moisture-retaining ability and presence
of organic materials in their skeletal framework (Gorjanc et al. 2010).
Gorjanc et al. studied the effect of plasma treatment on the adhesion of silver
nanoparticles on cotton fabric and antimicrobial effect of silver nanoparticles on
plasma-treated and plasma-untreated fabrics against E. coli and P. aeruginosa bacteria. They treated cotton fabric in CF 4 gas created in an RF plasma system for
10 s. SEM images showed that untreated cotton had a smoother surface, whereas the
plasma-treated surface appeared non-structured due to etching by F and O radicals
which led to a dramatic increase in surface roughness and hence to higher adsorption of silver nanoparticles. Plasma treatment effect could sustain up to ten washing
cycles as the quantity of silver on plasma-treated and washed samples did not show
much variation in the tests. The antimicrobial efficacy of silver nanoparticles was also
proved with reasonable reduction of more than 77 and 68% in P. aeruginosa and E.
coli, respectively, in plasma-treated and silver nanoparticle-loaded samples (Gorjanc
et al. 2010, 2013). Shahidi and Ghoranneviss deposited a nanolayer of silver ions on
cotton fabric using a DC magnetron sputtering system. A silver anode and cathode
were used, and samples placed on anode were sputtered with metal particles on both
sides. The cotton fabric kept on anode were functionalised with low-pressure plasma
for different exposure times (10, 150, 300 s) and different gas pressures (0.002, 0.05,
0.08 Torr) divided into nine runs with a combination of treatment time and gas pressure. The changes in surface topology with rough and etched surface and deposited
silver nanoparticles are visible in SEM images plasma-treated cotton samples. The
highest amount of deposited silver was 1.018% for run 6 which was at 0.05 Torr gas
pressure and 300 s of treatment time which reduced to 0.998% after ten washing
cycles. This shows that the durability of silver ions is maintained even after repeated
laundering. The bacterial counting test showed a 100% reduction of bacteria, E. coli
545
and strong antimicrobial effects in its ionic state (Ag
+ ) (Deng et al. 2015). Zinc oxide
(ZnO) nanoparticles possess excellent photocatalytic activity, superior UV blocking
capacity, as well as antifungal and antibacterial properties (Rezaei 2016). ZnO is an
inexpensive and abundant material. The use of nanoparticles has been done extensively to enhance the antimicrobial activity of textile materials as their size is similar
to that of most biological molecules. Therefore, they can easily penetrate the organic
matrix and can be used for in vivo and in vitro medical research. Metallic oxides or
metals in ionic states are toxic to bacteria even at low concentrations. The various
mechanisms responsible for the action have been proposed. Binding to intracellular
proteins and inactivating the bacteria or damage to microbial cell wall due to reactive oxygen species are some of the reported effects of metal nanoparticles (Shahidi
2018). However, their immobilisation on textile material is a challenge which can
be overcome by pretreatment of fabric by plasma, and many studies have reported
favourable results (Airoudj et al. 2014).
Cellulose is the most prevalent natural biopolymer on this planet, assimilating
many important properties like bioavailability, biodegradability and biocompatibility.
Cotton is the natural fibre which is composed of 95% cellulose. It is the primary source
of sustainable clothing material with the highest demand due to being comfortable
to wear and easy to maintain. Natural cellulose materials are easily attacked by
microbes like bacteria and fungi due to their moisture-retaining ability and presence
of organic materials in their skeletal framework (Gorjanc et al. 2010).
Gorjanc et al. studied the effect of plasma treatment on the adhesion of silver
nanoparticles on cotton fabric and antimicrobial effect of silver nanoparticles on
plasma-treated and plasma-untreated fabrics against E. coli and P. aeruginosa bacteria. They treated cotton fabric in CF 4 gas created in an RF plasma system for
10 s. SEM images showed that untreated cotton had a smoother surface, whereas the
plasma-treated surface appeared non-structured due to etching by F and O radicals
which led to a dramatic increase in surface roughness and hence to higher adsorption of silver nanoparticles. Plasma treatment effect could sustain up to ten washing
cycles as the quantity of silver on plasma-treated and washed samples did not show
much variation in the tests. The antimicrobial efficacy of silver nanoparticles was also
proved with reasonable reduction of more than 77 and 68% in P. aeruginosa and E.
coli, respectively, in plasma-treated and silver nanoparticle-loaded samples (Gorjanc
et al. 2010, 2013). Shahidi and Ghoranneviss deposited a nanolayer of silver ions on
cotton fabric using a DC magnetron sputtering system. A silver anode and cathode
were used, and samples placed on anode were sputtered with metal particles on both
sides. The cotton fabric kept on anode were functionalised with low-pressure plasma
for different exposure times (10, 150, 300 s) and different gas pressures (0.002, 0.05,
0.08 Torr) divided into nine runs with a combination of treatment time and gas pressure. The changes in surface topology with rough and etched surface and deposited
silver nanoparticles are visible in SEM images plasma-treated cotton samples. The
highest amount of deposited silver was 1.018% for run 6 which was at 0.05 Torr gas
pressure and 300 s of treatment time which reduced to 0.998% after ten washing
cycles. This shows that the durability of silver ions is maintained even after repeated
laundering. The bacterial counting test showed a 100% reduction of bacteria, E. coli