3.5 Antibacterial Activity of Carbon Quantum Dot-Based
Nanocomposites
Microbial pollution is the biggest and most challenging menace for individuals as
overusing fluoroquinolone, chloramphenicol, and trimethoprim antibiotics makes
multiple drug-resistant bacteria which are difficult to remove (Levy and Marshall
2004). With the advancement in nanoscience, antimicrobial nanomedicine also
becomes a prominent field for the researcher to device some nanomaterial for
microbial pollution. Previously, metals (Ag and Au) or metal oxide (CuO, ZnO
and Fe 2 O 3 ) nanoparticles were reported having antibacterial properties (Hoseinnejad
et al. 2018; Pare et al. 2008, 2009; Raghunath and Perumal 2017). These earlier
devised nanomaterials suffer with limitation of biological toxicity, generation of
secondary pollutant, low efficiency, and poor degradation.
Recently, less toxic, environmental-friendly, and biocompatible carbonaceous
materials have identified as promising antimicrobial agents. Li et al. (2018b) fabricated less toxic, biodegradable, and broad-spectrum antibacterial and antifungal
carbon dots from vitamin C using electrochemical technique. Carbon dots displayed
antibacterial activity, by destroying bacterial cell wall even at lower concentration.
At the end, carbon dots are completely degraded into innoxious product in the visible
region or at low temperature. The antibacterial activity of carbon dots is evaluated
against Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gramnegative (Bacillus sp. WL-6 and Escherichia coli) bacteria, whereas their antifungal
properties were evaluated against two pathogenic fungi, Rhizoctonia solani and
Pyricularia grisea.
Kovacova et al. (2018) investigated the photocatalytic and antibacterial activity of
hydrophobic carbon quantum dots/polyurethane nanocomposites synthesized by
swell–encapsulation–shrink method. The nanocomposites had shown bactericidal
effect against Staphylococcus aureus and Escherichia coli for 60 min of irradiation
of blue light, whereas the photocatalytic degradation of Rose Bengal dye was
observed for 180 min. Habiba et al. (2015) fabricated Ag nanoparticle-decorated
graphene quantum dots via pulse laser method. The antibacterial activity of Ag–
graphene quantum dots, bare graphene quantum dots, and Ag nanoparticle were
compared. The symbiotic effect of Ag and graphene quantum dots in Ag–graphene
quantum dot nanocomposites enhances the antibacterial property in comparison to
Ag and graphene quantum dots.
Dong et al. (2017) employed carbon dots with other antibacterial agents such as
H 2 O 2 , CH 3 COOH, and Na 2 CO 3 . The photoactivated technology for antibacterial
property is a rapidly growing field to prevent microbial pollution. Carbon quantum
dot nanocomposites possess bactericidal property and can be utilized to remove
photocatalyzed antimicrobial pollution. The antibacterial property of carbon-based
nanocomposites can be easily tailored by surface modification. Liu et al. (2018)
fabricated ZnO/graphene quantum dot nanocomposites using hydrothermal method
and assessed their antibacterial property through minimum inhibitory concentration,
and decreases in bacterial colony were counted by plate count method. The
106
P. Shandilya et al.
Nanocomposites
Microbial pollution is the biggest and most challenging menace for individuals as
overusing fluoroquinolone, chloramphenicol, and trimethoprim antibiotics makes
multiple drug-resistant bacteria which are difficult to remove (Levy and Marshall
2004). With the advancement in nanoscience, antimicrobial nanomedicine also
becomes a prominent field for the researcher to device some nanomaterial for
microbial pollution. Previously, metals (Ag and Au) or metal oxide (CuO, ZnO
and Fe 2 O 3 ) nanoparticles were reported having antibacterial properties (Hoseinnejad
et al. 2018; Pare et al. 2008, 2009; Raghunath and Perumal 2017). These earlier
devised nanomaterials suffer with limitation of biological toxicity, generation of
secondary pollutant, low efficiency, and poor degradation.
Recently, less toxic, environmental-friendly, and biocompatible carbonaceous
materials have identified as promising antimicrobial agents. Li et al. (2018b) fabricated less toxic, biodegradable, and broad-spectrum antibacterial and antifungal
carbon dots from vitamin C using electrochemical technique. Carbon dots displayed
antibacterial activity, by destroying bacterial cell wall even at lower concentration.
At the end, carbon dots are completely degraded into innoxious product in the visible
region or at low temperature. The antibacterial activity of carbon dots is evaluated
against Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gramnegative (Bacillus sp. WL-6 and Escherichia coli) bacteria, whereas their antifungal
properties were evaluated against two pathogenic fungi, Rhizoctonia solani and
Pyricularia grisea.
Kovacova et al. (2018) investigated the photocatalytic and antibacterial activity of
hydrophobic carbon quantum dots/polyurethane nanocomposites synthesized by
swell–encapsulation–shrink method. The nanocomposites had shown bactericidal
effect against Staphylococcus aureus and Escherichia coli for 60 min of irradiation
of blue light, whereas the photocatalytic degradation of Rose Bengal dye was
observed for 180 min. Habiba et al. (2015) fabricated Ag nanoparticle-decorated
graphene quantum dots via pulse laser method. The antibacterial activity of Ag–
graphene quantum dots, bare graphene quantum dots, and Ag nanoparticle were
compared. The symbiotic effect of Ag and graphene quantum dots in Ag–graphene
quantum dot nanocomposites enhances the antibacterial property in comparison to
Ag and graphene quantum dots.
Dong et al. (2017) employed carbon dots with other antibacterial agents such as
H 2 O 2 , CH 3 COOH, and Na 2 CO 3 . The photoactivated technology for antibacterial
property is a rapidly growing field to prevent microbial pollution. Carbon quantum
dot nanocomposites possess bactericidal property and can be utilized to remove
photocatalyzed antimicrobial pollution. The antibacterial property of carbon-based
nanocomposites can be easily tailored by surface modification. Liu et al. (2018)
fabricated ZnO/graphene quantum dot nanocomposites using hydrothermal method
and assessed their antibacterial property through minimum inhibitory concentration,
and decreases in bacterial colony were counted by plate count method. The
106
P. Shandilya et al.