Designing Novel Photocatalysts for Disinfection of Multidrug-Resistant …
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aeration rate. Interesting observations were made, that TiO 2 –Kaolinite photocatalyst
was operable under a wider pH range up to 7.0 in contrast to other conventional
photocatalysts. However, a very low PCD rate was achieved at pH 10.0, which is
related due to variation in surface charge or PZC (TiO 2 –Kaolinite) that weakens the
bacteria catalyst interaction.
The use of clay-based photocatalytic nanocomposite is not only restricted to
water-based disinfection process. Their applications have been extended to food
packaging materials as well. In the late 1980s, Toyota research group reported pronounced improvements in nylon-6 (N6)/montmorillonite (MMT) nanocomposite for
their thermal, gas barrier, and mechanical properties. Nanosized clays confer several
benefits over conventional micro-sized clays in polymer matrix. This laid the foundation for polymer/clay nanocomposites in various industrial packaging applications.
These systems prolong the food shelf life via curbing of humidity, oxygen, ethylene,
aroma, or unfamiliar flavors interacting with the food. Most importantly, the presence
of clay restricts the growth of foodborne contaminating bacteria and fungus. Bodaghi
et al. (2014) reported about low-density polyethylene (LDPE) nanocomposite films
with two types of NPs, TiO 2 (3 wt%) and Closite 20A (3 and 5 wt%), synthesized using a melt blow extrusion method (Bodaghi et al. 2013). These NCs showed
more mechanical reinforcement, increased gas barrier than their conventional counterparts. Moreover, in 8 Watts UV lamp, tremendous photocatalytic inactivation of
Pseudomonas spp. and Rhodotorula mucilaginosa and degradation of ethylene was
achieved in presence of these LDPE-based nanocomposite film that consisted of two
kinds of NPs. This might find its application in fresh horticultural product packaging
as antimicrobial materials with reformed barrier properties.
Other than photocatalysis, clay founds huge application in antimicrobials. Pyrophyllite, a hydrous aluminosilicate clay mineral achieved 94% disinfection of E.
coli in solution even while bicarbonates were situated (Kang et al. 2013). Blended
Bentonite–polymer composites were also used as antimicrobials. Their blends with
sand, zeolite, vermicompost, and charcoal in the form of a filter could intensify
their actions and help removal of coliform bacteria from water samples, thus acting as a great source of decontamination in rural areas where resources are limited.
Intercalated Montmorillonite, Vermiculite, Palygorskite, and Kaolin with quaternary phosphonium salt and their antibacterial properties were successfully reported
against E. coli ATCC 25922 and Staphylococci aureus ATCC 6538. This antimicrobial activity depends on the amount of phosphonium surfactant released, the surface
charge and particle size of the adsorbents or organo-clay minerals. According to Wu
et al. (2011) increasing the release of phosphonium surfactant, increasing zeta potential (positive charges) and then narrow particle size distribution of the organo-clay
adsorbent boosts its antimicrobial proficiency.
459
aeration rate. Interesting observations were made, that TiO 2 –Kaolinite photocatalyst
was operable under a wider pH range up to 7.0 in contrast to other conventional
photocatalysts. However, a very low PCD rate was achieved at pH 10.0, which is
related due to variation in surface charge or PZC (TiO 2 –Kaolinite) that weakens the
bacteria catalyst interaction.
The use of clay-based photocatalytic nanocomposite is not only restricted to
water-based disinfection process. Their applications have been extended to food
packaging materials as well. In the late 1980s, Toyota research group reported pronounced improvements in nylon-6 (N6)/montmorillonite (MMT) nanocomposite for
their thermal, gas barrier, and mechanical properties. Nanosized clays confer several
benefits over conventional micro-sized clays in polymer matrix. This laid the foundation for polymer/clay nanocomposites in various industrial packaging applications.
These systems prolong the food shelf life via curbing of humidity, oxygen, ethylene,
aroma, or unfamiliar flavors interacting with the food. Most importantly, the presence
of clay restricts the growth of foodborne contaminating bacteria and fungus. Bodaghi
et al. (2014) reported about low-density polyethylene (LDPE) nanocomposite films
with two types of NPs, TiO 2 (3 wt%) and Closite 20A (3 and 5 wt%), synthesized using a melt blow extrusion method (Bodaghi et al. 2013). These NCs showed
more mechanical reinforcement, increased gas barrier than their conventional counterparts. Moreover, in 8 Watts UV lamp, tremendous photocatalytic inactivation of
Pseudomonas spp. and Rhodotorula mucilaginosa and degradation of ethylene was
achieved in presence of these LDPE-based nanocomposite film that consisted of two
kinds of NPs. This might find its application in fresh horticultural product packaging
as antimicrobial materials with reformed barrier properties.
Other than photocatalysis, clay founds huge application in antimicrobials. Pyrophyllite, a hydrous aluminosilicate clay mineral achieved 94% disinfection of E.
coli in solution even while bicarbonates were situated (Kang et al. 2013). Blended
Bentonite–polymer composites were also used as antimicrobials. Their blends with
sand, zeolite, vermicompost, and charcoal in the form of a filter could intensify
their actions and help removal of coliform bacteria from water samples, thus acting as a great source of decontamination in rural areas where resources are limited.
Intercalated Montmorillonite, Vermiculite, Palygorskite, and Kaolin with quaternary phosphonium salt and their antibacterial properties were successfully reported
against E. coli ATCC 25922 and Staphylococci aureus ATCC 6538. This antimicrobial activity depends on the amount of phosphonium surfactant released, the surface
charge and particle size of the adsorbents or organo-clay minerals. According to Wu
et al. (2011) increasing the release of phosphonium surfactant, increasing zeta potential (positive charges) and then narrow particle size distribution of the organo-clay
adsorbent boosts its antimicrobial proficiency.