202
S. James
7.3 Quantum Dots
Quantum dots are 2–10 nanometer-sized artificial crystals that have peculiar properties. Quantum dots show size-dependent emissions, favors labeling and tracking of
stem cells. [13]. Quantum dots exhibit high fluorescence stability, a nerve regeneration study in rats where stem cells labeled quantum dots are detected 35 days after
transplantation [14]. Quantum dots provide comprehensive tracking property. In a
study, injecting quantum dots with cell-penetrating lipopeptides, into the brains of
embryonic chicks, made them track and identify neural stem cells [15].
8 Nanomaterials in Clinical Applications
8.1 Antibacterial /Sepsis Therapy
Sepsis is a life-threatening condition in response to the body fighting against severe
infections, further leading to hemodynamic instability, failure of the vital organs,
shock, and eventually death [16]. Several therapeutic protocols have implemented to
prevent sepsis and septic shock [17]. However, there seem to be significant mortality
rates secondary to sepsis. Recently researchers proposed nanoparticle-based diagnoses and treatments for sepsis [17]. An optimal size, surface, and composition
have a longer circulation half-life than the free drug counterpart [18]. Hence, these
drug nanoparticles can afford the time and exposure to neutralize pathogens and
their molecular patterns in the blood and at the sites of infection [19]. When the
nanoparticles were conjugated with poorly soluble drugs, it helped to disperse them
in the aqueous medium and increased their bioavailability [17]. Sondi and SalopekSondi have explored Silver nanoparticles as an antimicrobial agent [20]. These silver
nanoparticles induce toxicity and cause damage to the bacterial cell membrane by
having a high affinity for the membrane [21]. Silver nanoparticles also serve as
a repository of Ag + ions, which form stable additions with cellular components
to inactivate a broad spectrum of bacteria [21]. Pal and colleagues found that silver
nanoparticles undergo shape-dependent interaction with the gram-negative bacterium
E. coli [22]. The shape of the silver nanoparticles plays a significant role in their interactions with bacterial membranes [22]. The antibacterial activity varies not only with
the shape but also by their size. Because of their smaller size, they affect the mobility
of nanoparticles and the dissolution rate of Ag + ions [22]. Silver is a metal known
to have an insignificant risk in humans and eliminated by the liver and kidneys [23].
However, the long-term safety of systemically administered silver remains to be
determined.
A study reports on a new antimicrobial agent SNAPP (structurally nanoengineered antimicrobial peptide polymers) [24]. SNAPPs demonstrate sub micromolecular activity against a broad range of pathogens due to the high local concentration of
cationic peptides [24]. In a rat in vivo experiment, they induced peritonitis by colistin
S. James
7.3 Quantum Dots
Quantum dots are 2–10 nanometer-sized artificial crystals that have peculiar properties. Quantum dots show size-dependent emissions, favors labeling and tracking of
stem cells. [13]. Quantum dots exhibit high fluorescence stability, a nerve regeneration study in rats where stem cells labeled quantum dots are detected 35 days after
transplantation [14]. Quantum dots provide comprehensive tracking property. In a
study, injecting quantum dots with cell-penetrating lipopeptides, into the brains of
embryonic chicks, made them track and identify neural stem cells [15].
8 Nanomaterials in Clinical Applications
8.1 Antibacterial /Sepsis Therapy
Sepsis is a life-threatening condition in response to the body fighting against severe
infections, further leading to hemodynamic instability, failure of the vital organs,
shock, and eventually death [16]. Several therapeutic protocols have implemented to
prevent sepsis and septic shock [17]. However, there seem to be significant mortality
rates secondary to sepsis. Recently researchers proposed nanoparticle-based diagnoses and treatments for sepsis [17]. An optimal size, surface, and composition
have a longer circulation half-life than the free drug counterpart [18]. Hence, these
drug nanoparticles can afford the time and exposure to neutralize pathogens and
their molecular patterns in the blood and at the sites of infection [19]. When the
nanoparticles were conjugated with poorly soluble drugs, it helped to disperse them
in the aqueous medium and increased their bioavailability [17]. Sondi and SalopekSondi have explored Silver nanoparticles as an antimicrobial agent [20]. These silver
nanoparticles induce toxicity and cause damage to the bacterial cell membrane by
having a high affinity for the membrane [21]. Silver nanoparticles also serve as
a repository of Ag + ions, which form stable additions with cellular components
to inactivate a broad spectrum of bacteria [21]. Pal and colleagues found that silver
nanoparticles undergo shape-dependent interaction with the gram-negative bacterium
E. coli [22]. The shape of the silver nanoparticles plays a significant role in their interactions with bacterial membranes [22]. The antibacterial activity varies not only with
the shape but also by their size. Because of their smaller size, they affect the mobility
of nanoparticles and the dissolution rate of Ag + ions [22]. Silver is a metal known
to have an insignificant risk in humans and eliminated by the liver and kidneys [23].
However, the long-term safety of systemically administered silver remains to be
determined.
A study reports on a new antimicrobial agent SNAPP (structurally nanoengineered antimicrobial peptide polymers) [24]. SNAPPs demonstrate sub micromolecular activity against a broad range of pathogens due to the high local concentration of
cationic peptides [24]. In a rat in vivo experiment, they induced peritonitis by colistin