148
S. Riaz and M. Ashraf
for 15–20 min in chitosan emulsion by ultrasonic vibrator. Three gauze samples were
prepared and treated with chitosan, nano-TiO 2 and nano-TiO 2 /chitosan emulsion
hen their antibacterial assessment showed highest antibacterial activity for nanoTiO 2 /chitosan composite emulsion. against E. coli, A. niger and C. albicans [113].
That was a new development of antibacterial green textile, to be used for medical
application especially for wound care.
7.2.4 Zinc Oxide Nanoparticles and Composites
Recently, ZnO has found applications in textile as antibacterial agent. It appears to
be promising functionalizing agent due to its selective toxicity towards prokaryotic
and eukaryotic [114]. It has been applied to textiles to render them antibacterial.
Different mechanisms may be involved for inhibition of bacterial growth or killing
of bacteria. First, due to structure of nanomaterial, because various nanostructures
can be grown on different materials [88, 101]. Such structure disintegrate the bacterial
cell membrane by damaging it mechanically, causing death of bacteria [102]. Second,
due to generation of oxygen reactive species like OH
• , H 2 O 2 , O 2
•−2 that penetrates
into cell membrane, inhibiting metabolic activities and later death of cell [115].
Another possibility is leaching of Zn
++ ions that attach to the bacterial surface due to
electrostatic attraction as bacterial cell wall carries negative charge, inhibiting further
growth [116].
ZnO nanomaterials are applied on different textile substrates like polyester, cotton, their blend etc. to impart multifunctional attributes. ZnO NPs of different size
were synthesized, polyester knitted fabrics was dip coated in nano-ZnO aqueous
suspension containing binder to enhance adhesion of NPs with hydrophobic surface.
The treated polyester fabric showed antibacterial activity up to 10 washes against S.
aureus and K. pneumoniae [37]. Instead of ZnO NPs Ashraf et al. [117] functionalized polyester fabric by the growth of ZnO NRs using hydrothermal fabrication
process. ZnO NPs were coated on plasma modified textile substrate by pad-dry-cure
method, to make seeded fabric. Fabric was dried at 120 °C for 2 min and then cured
at 170 °C for about 8 min. Then, ZnO NRs were grown on seeded fabric, by placing
fabric in reagents solution at 90 °C for 4 h. Qualitative and quantitative antibacterial
assessment showed high efficacy of ZnO NRs against bacterial strains S. aureus and
E. coli. To make multi-functional textile that was used as biosensor or pesticides, ZnO
NRs were grown on conductive textile substrate consisting of silver (55%) and nylon
(45%). Zinc acetate and potassium hydroxide (KOH) solution was made in methanol
at 60 °C temperature for 2 h by continuous stirring. Textile sample was heated at
100 °C in prepared solution to make seed over which the ZnO NRs were grown in an
oven at 90 °C for about 6 h, then, cleaning and drying of finished conductive textile
was done. ZnO NRs based functional textile exhibited excellent photocatalytic and
antibacterial activity along with sensing properties. Such concept of smart textile
for wearable sensing without any odor and bacterial growth was given first time by
Hatamie et al. [118], after the commercially available silver based product that is considered hazardous to health because of its toxicity [107]. For biomedical application
S. Riaz and M. Ashraf
for 15–20 min in chitosan emulsion by ultrasonic vibrator. Three gauze samples were
prepared and treated with chitosan, nano-TiO 2 and nano-TiO 2 /chitosan emulsion
hen their antibacterial assessment showed highest antibacterial activity for nanoTiO 2 /chitosan composite emulsion. against E. coli, A. niger and C. albicans [113].
That was a new development of antibacterial green textile, to be used for medical
application especially for wound care.
7.2.4 Zinc Oxide Nanoparticles and Composites
Recently, ZnO has found applications in textile as antibacterial agent. It appears to
be promising functionalizing agent due to its selective toxicity towards prokaryotic
and eukaryotic [114]. It has been applied to textiles to render them antibacterial.
Different mechanisms may be involved for inhibition of bacterial growth or killing
of bacteria. First, due to structure of nanomaterial, because various nanostructures
can be grown on different materials [88, 101]. Such structure disintegrate the bacterial
cell membrane by damaging it mechanically, causing death of bacteria [102]. Second,
due to generation of oxygen reactive species like OH
• , H 2 O 2 , O 2
•−2 that penetrates
into cell membrane, inhibiting metabolic activities and later death of cell [115].
Another possibility is leaching of Zn
++ ions that attach to the bacterial surface due to
electrostatic attraction as bacterial cell wall carries negative charge, inhibiting further
growth [116].
ZnO nanomaterials are applied on different textile substrates like polyester, cotton, their blend etc. to impart multifunctional attributes. ZnO NPs of different size
were synthesized, polyester knitted fabrics was dip coated in nano-ZnO aqueous
suspension containing binder to enhance adhesion of NPs with hydrophobic surface.
The treated polyester fabric showed antibacterial activity up to 10 washes against S.
aureus and K. pneumoniae [37]. Instead of ZnO NPs Ashraf et al. [117] functionalized polyester fabric by the growth of ZnO NRs using hydrothermal fabrication
process. ZnO NPs were coated on plasma modified textile substrate by pad-dry-cure
method, to make seeded fabric. Fabric was dried at 120 °C for 2 min and then cured
at 170 °C for about 8 min. Then, ZnO NRs were grown on seeded fabric, by placing
fabric in reagents solution at 90 °C for 4 h. Qualitative and quantitative antibacterial
assessment showed high efficacy of ZnO NRs against bacterial strains S. aureus and
E. coli. To make multi-functional textile that was used as biosensor or pesticides, ZnO
NRs were grown on conductive textile substrate consisting of silver (55%) and nylon
(45%). Zinc acetate and potassium hydroxide (KOH) solution was made in methanol
at 60 °C temperature for 2 h by continuous stirring. Textile sample was heated at
100 °C in prepared solution to make seed over which the ZnO NRs were grown in an
oven at 90 °C for about 6 h, then, cleaning and drying of finished conductive textile
was done. ZnO NRs based functional textile exhibited excellent photocatalytic and
antibacterial activity along with sensing properties. Such concept of smart textile
for wearable sensing without any odor and bacterial growth was given first time by
Hatamie et al. [118], after the commercially available silver based product that is considered hazardous to health because of its toxicity [107]. For biomedical application