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J. A. Elegbede and A. Lateef
disorder, mainly human Cerebral Cavernous Malformation (CCM) disease, which is
connected to a noteworthy rise in intracellular ROS levels were examined, and note
worthily, it was observed that Pt nanozymes proficiently reduced ROS levels and
completely restored the physiological homeostasis of the cell.
Samuel et al. (2015) reported that nontoxic hydrophilic carbon cluster nanoparticles displayed the capacity to directly convert of superoxide to hydrogen peroxide
and dioxygen. This was achieved faster than in most natural enzymes, and this is
exactly what dificiency in dioxygen need in an injured state where ROS particularly superoxide, overpower the natural enzymes required to eliminate superoxide.
It was confirmed that the hydrophilic carbon clusters produced no reaction against
nitric oxide radical, a strong vasodilator that has a noteworthy function in cytoprotection and neurotransmission. Also, Ragg et al. (2016) demonstrated that manganese
oxide (MnO) nanoparticles (NPs) produced a basic superoxide dismutase (SOD)like activity, which was superior to that of the natural Mn-dependent SOD. The
MnONPs were synthesized according to an approach described by Schladt et al.
(2009) with 40 mM manganese (II) chloride tetrahydrate as precausor. Along with
the SOD-like property displayed, the MnONPs appreciably improved the magnetic
resonance imaging (MRI) contrast on exposure to superoxide radicals, which made
them responsive MRI contrast agents for the imaging and treatment of cancer cells
with diminished SOD levels. Lastly, Kamada and Soh (2015) reported that colloidal
solutions of Ce-doped titanate nanosheets (Ce-TNS) with tiny dimensions of around
10 nm were fabricated through hydrolysis reaction of titanium tetra isopropoxide and
Ce(NO 3 ) 3 , and their potentials for annihilation of reactive oxygen species (ROS)
were investigated. The results obtained indicated that Ce-TNS possessed inherent
SOD mimetic potentials to obliterate of superoxide anion radicals (O 2
– ) as target
ROS. Moreover, the Ce-TNS was revealed to protect DNA molecules from oxidative
damage induced by ultraviolet light.
3.1.5 Hydrolase-Like Nanomaterials
Some nanomaterials have been described in recent times to act as nanozymes
presenting hydrolase-like potentials which spans through activities as proteases,
amidases, nucleases and phosphesterases among others. Protein misfolding to
amyloid aggregates is a major feature for neurodegenerative diseases, and recently,
a lot of concentration has been to inspect natural proteases with competence of
degrading amyloid-β peptides (Aβ), but majority of the screened ones are difficult to
apply in the clinics having intractable problem of immunogenicity in living organisms; thus, the need arose for the exploitation of artificial enzymes that can overcome
this challenge. Guan et al. (2016) described the prototype of a proteolytic enzyme
by coating Ceria nanoparticles (CeONP) with Polyoxometalates (POMs) resulting
in Ceria/Polyoxometalates hybrid (CeONP@POMs). CeONP was fabricated by
reacting 1 M cerium (III) nitrate to 30.0 ml ammonium hydroxide which resulted in
a color development from deep brown to light yellow. Then CeONP was redissolved
in distilled water and reacted with a solution containing POMs (10 mg/mL) which
J. A. Elegbede and A. Lateef
disorder, mainly human Cerebral Cavernous Malformation (CCM) disease, which is
connected to a noteworthy rise in intracellular ROS levels were examined, and note
worthily, it was observed that Pt nanozymes proficiently reduced ROS levels and
completely restored the physiological homeostasis of the cell.
Samuel et al. (2015) reported that nontoxic hydrophilic carbon cluster nanoparticles displayed the capacity to directly convert of superoxide to hydrogen peroxide
and dioxygen. This was achieved faster than in most natural enzymes, and this is
exactly what dificiency in dioxygen need in an injured state where ROS particularly superoxide, overpower the natural enzymes required to eliminate superoxide.
It was confirmed that the hydrophilic carbon clusters produced no reaction against
nitric oxide radical, a strong vasodilator that has a noteworthy function in cytoprotection and neurotransmission. Also, Ragg et al. (2016) demonstrated that manganese
oxide (MnO) nanoparticles (NPs) produced a basic superoxide dismutase (SOD)like activity, which was superior to that of the natural Mn-dependent SOD. The
MnONPs were synthesized according to an approach described by Schladt et al.
(2009) with 40 mM manganese (II) chloride tetrahydrate as precausor. Along with
the SOD-like property displayed, the MnONPs appreciably improved the magnetic
resonance imaging (MRI) contrast on exposure to superoxide radicals, which made
them responsive MRI contrast agents for the imaging and treatment of cancer cells
with diminished SOD levels. Lastly, Kamada and Soh (2015) reported that colloidal
solutions of Ce-doped titanate nanosheets (Ce-TNS) with tiny dimensions of around
10 nm were fabricated through hydrolysis reaction of titanium tetra isopropoxide and
Ce(NO 3 ) 3 , and their potentials for annihilation of reactive oxygen species (ROS)
were investigated. The results obtained indicated that Ce-TNS possessed inherent
SOD mimetic potentials to obliterate of superoxide anion radicals (O 2
– ) as target
ROS. Moreover, the Ce-TNS was revealed to protect DNA molecules from oxidative
damage induced by ultraviolet light.
3.1.5 Hydrolase-Like Nanomaterials
Some nanomaterials have been described in recent times to act as nanozymes
presenting hydrolase-like potentials which spans through activities as proteases,
amidases, nucleases and phosphesterases among others. Protein misfolding to
amyloid aggregates is a major feature for neurodegenerative diseases, and recently,
a lot of concentration has been to inspect natural proteases with competence of
degrading amyloid-β peptides (Aβ), but majority of the screened ones are difficult to
apply in the clinics having intractable problem of immunogenicity in living organisms; thus, the need arose for the exploitation of artificial enzymes that can overcome
this challenge. Guan et al. (2016) described the prototype of a proteolytic enzyme
by coating Ceria nanoparticles (CeONP) with Polyoxometalates (POMs) resulting
in Ceria/Polyoxometalates hybrid (CeONP@POMs). CeONP was fabricated by
reacting 1 M cerium (III) nitrate to 30.0 ml ammonium hydroxide which resulted in
a color development from deep brown to light yellow. Then CeONP was redissolved
in distilled water and reacted with a solution containing POMs (10 mg/mL) which