Spectrum of Emerging
Sciences, 2 (1) 2022, 36-44
Green Synthesis of
Zinc Oxide Nanomaterial
Roli
Jain
Department
of Chemistry, Dr. Hari Singh Gour University, Sagar, Madhya Pradesh, India.
*Corresponding
Author:
E-mail
Address: rolijainchem@gmail.com
Article available online at: Article
available online at: https://esciencesspectrum.com/AbstractView.aspx?PID=2022-1-2-6
ARTICLE INFO
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ABSTRACT
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Original Research
Article
Received: 18 August 2022
Accepted: 30 August 2022
DOI
10.55878/SES2021-1-2-6
KEYWORDS
Zinc oxide nanomaterials
(ZnONPs) ,
Green synthesis,
Antimicrobial activity, Minimum
inhibitory concentration.
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An emerging subfield within the science
of nanotechnology is the green production of nanoparticles by the use of
biological systems, particularly plant extracts. Due to the various features
that it possesses, zinc oxide is of great relevance to a wide variety of
sectors. These properties have been further improved by the manufacturing of
this material at the nanoscale. Despite this, there has been a rise in
concern over the influence that it has on the environment, which has resulted
in the creation of manufacturing methods that are favorable to the
environment. There has been a recent uptick in interest, as reported in the
scientific literature, in producing metal and metal oxide nanoparticles by
the use of biological methods. Because it is a less dangerous procedure than
chemical and physical synthesis methods, which are currently employed in the
industry to create these nanomaterials, this approach was given the name
"green synthesis." The extraction of coffee leaves is used as a
reducing agent to maintain the stability of the particle length. In terms of
its medicinal potential, the results indicated that it had a significant
antibacterial effect against the pathogenic kind of bacteria that developed
on the wound. The current study focuses on the environmentally friendly
manufacture of zinc oxide nanoparticles (ZnO NPs) as well as their
application in the process of toxicity reduction. It is likely that the use
of ZnO nanoparticles as antibacterial agents will be their most important
use. Because of their increased surface area and decreased size, these
particles are an excellent candidate for use as an antibacterial agent. This
article provides an overview of the environmentally friendly production of
ZnO nanoparticles as well as the antibacterial properties of these particles.
In addition to this, the activity's mechanism was analysed as well. Also
featured was the environmentally friendly production of ZnO nanoparticles
from Azadirachta indica, Aloe vera, Murraya koenigii, and Anisochilus
carnosus.
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An explosive strategic development
has lately been utilised often in the creation of revolutionary green synthesis
procedures. This is due to the fact that it is theoretically possible to
construct smart bio-nanomaterials that have unique biological characteristics.
These processes yield nanoscale biocompatible nanomaterials. In recent years,
non-toxic, biomimetic, environmentally friendly methods have been gaining more
importance due to their capacity to form a wide range of biocompatible
nanomaterials, which paves the way to best suited for biomedical applications.
The reason for this rise in importance is due to the fact that these methods
can form a wide variety of biocompatible nanomaterials. This is due to the fact
that these approaches may produce nanomaterials that are biocompatible. Due to
the fact that these nanomaterials exhibit excellent antibacterial qualities and
are appropriate for use in biomedical applications[1] [2], the creation of zinc
oxide nanoparticles in general has gained a substantial amount of interest.
In this particular piece of research,
unique biomimetic syntheses of bioinspired zinc oxide nanoparticles have been
investigated while taking place in the presence of rambutan extract polyphenol.
There are several natural foodstuffs that contain polyphenolic chemicals. Some
examples of these goods are fruits, vegetables, drinks (tea, wine, and juices),
honey, chocolate, and herbs. Because of the positive implications that they
have for human health, there is a lot of interest in them. Because of their
ability to act as antioxidants and the correlation between them and a number of
pathological illnesses, including hypertension, cardiovascular disease,
dementia, and even cancer, they have been the subject of a significant amount
of research. Because this approach utilises rambutan, which possesses general
properties such as a waste resource material, a natural ligation agent, and
potent phenolic antioxidants, this is especially helpful because this method
uses rambutan for creative biomedical applications[3] [4] . The potential
application of rambutan peels in the food business as well as the medical
sector is due to the presence of key components in rambutan peels. These key
components include ellagic acid, corilagin, geranin, and ellagitannins. The
extract of rambutan peel has been shown to have antibacterial properties,
particularly against pathogenic microorganisms. As a result, the purpose of
this work was to investigate the effect that the peel extract of Nephelium
lappaceum L. has on the production of zinc oxide nanoparticles[5] [6] .
Nanotechnology is a multidisciplinary
field of study that focuses on the production of innovative materials at the
nanoscale (1–100 nm), which may then be utilised in a variety of applications.
The materials were able to acquire new properties at the nanoscale, “such as
large surface area, thermal conductivity, size, charge, shape, crystal
structure, surface morphology, and zeta potential”. These properties allow the
materials to be integrated into the biomedical and biotechnological sectors.
Nanomaterials (NPs) may be created by a variety of processes, some of which
include chemical, physical, and even biological procedures. The older chemical
and physical procedures involved the use of potentially harmful materials,
necessitated severe circumstances such as high temperatures, amounts of energy,
and levels of pressure, and thus produced potentially harmful byproducts. As a
result, there was a rise in interest in biological approaches or
environmentally friendly nanotechnology[7] [8].
A clean approach that is employed for
the synthesis of nanomaterials by removing or minimising the amount of
hazardous elements used during the manufacturing process is what is meant by
the term "green nanotechnology [9] [10]." The environmentally
friendly synthesis of NPs may be achieved by the utilisation of a wide variety
of biological entities, including “bacteria, actinomycetes, fungus,
cyanobacteria, macro-algae, and plants, amongst others. Green synthesis is
favoured over “chemical and physical” processes because it is better for the
environment, more cost-effective, easier to handle, can be scaled up, and is
compatible with living organisms”. In recent years, a number of NPs, including
Ag, Au, Cu, CuO, ZnO, Se, and others that are incorporated into a variety of
biological activities, have been manufactured using environmentally friendly
processes. Nanomaterials that are biogenically produced or greenly synthesised
provide a promising alternative antibacterial and anticancer agent for the
development of safer, more selective, and economically viable pharmaceuticals
or drug delivery vehicles[11] [12] [13].
The presence of various metabolites,
such as “proteins, enzymes, and other biomolecules that act as reducing,
capping, and stabilising agents, is attributed to the biogenic synthesis of
zinc oxide nanomaterials (ZnO-NPs) by biological entities. This is the case
because of the presence of different metabolites[14] [15]”. The many
characteristics of ZnO-NPs, including their form, size, dispersity, and
stability, may be traced back to the released metabolites. The reductase enzyme
that is released by microorganisms in growth media has the potential to carry
out the extracellular processes of ZnO-NPs. “NADH (Nicotinamide Adenine Dinucleotide
plus hydrogen ion)-dependent reductase enzymes act as electron carriers to
reduce zinc ions from zinc 2+ to zinc ions, which ultimately results in the
formation of zinc oxide nanoparticles (ZnO-NPs). At the same time, metal ions
were reduced to nanoscales by the action of the reductase enzymes, which
received electrons from NADH, which were then oxidised to produce NAD+[16] [17]
[18]”.
Because of its one-of-a-kind chemical
and physical features, which in turn boost their application aspects, zinc
oxide nanomaterials, also known as ZnO-NPs, are regarded to be the most
significant of the metal oxide nanoparticles (NPs). ZnO-
NPs have the potential to be utilised
in the rubber sector as a result of their capacity to produce wear-resistant
composites and their ability to boost the intensity and tenacity of rubber
[19]. In addition, because to the strong UV-absorption characteristics of
ZnO-NPs, “sunscreen and other cosmetic care products incorporate them into
their formulations [20][21]. In addition, ZnO-NPs are regarded as an excellent
semiconductor owing to the unique qualities that emerge at the nanoscale
structure, such as high electron mobility, broad bandgap, and high visual
transparency. These characteristics make ZnO-NPs suitable for use in electronic
devices. ZnO-NPs” are frequently used in the textile industry to give finished
materials increased resistance to the damaging effects of UV radiation, as well
as antibacterial and deodorant properties[22] [23]. The antifungal, concrete
manufacturing, solar cell, electrical, photocatalysis, and electrotechnology
sectors are some of the potential application areas for zinc oxide
nanoparticles (ZnO-NPs). “ZnO-NPs have recently been validated as additives to
dietary products in order to improve the growth performance, enhance the
antioxidant property and immune response, increase the quality of eggs, and
improve the production of layer chickens. All of these benefits can be achieved
through the use of ZnO-NPs[24]”. Main objective of the present work are
- To
study the activity of the synthesized eco-friendly ZnO NP against
different pathogen strains.
- Study
on green synthesis of zinc oxide nonmaterial.
RESEARCH
METHODOLOGY
Green Synthesis of Nanomaterials
The production of nanomaterials using
plants and biopolymers is an example of green synthesis of nanomaterials, which
is a technology that improves the usefulness of nanomaterials in “biomedical
applications. The development of this new method and the significant interest
in it are primarily related to the absence of toxic chemicals” or a high amount
of energy applied to the biological synthesis, which makes the process more
cost-effective and environmentally friendly. In addition, there is a
significant amount of interest in this new method [25] [26] [27]. “Furthermore,
the primary benefit of this method is that the raw materials that are used are
naturally abundant in amino, carboxyl, and hydroxyl groups. These are the types
of groups that are frequently utilised as stabilising or capping agents in
aqueous medium, which triggers the formation of nanomaterials. The green
synthesis of zinc nanoparticles is more ecologically friendly than the usual
physical or chemical procedures that are employed today, according to several
of the publications that are now accessible [28] 29] [30]”.
“Plant Mediated Synthesis of ZnO-NPs”
“The most prevalent type of
biological substrate utilised in the environmentally friendly production of
nanomaterials using metallic ions is plant matter. Because of the unique
phytochemicals that different plant parts generate, such as ZnO NPs, some plant
parts, such as leaves, stems, roots, fruits, and seeds, have been utilised in
their production. This may have something to do with the widely held belief
that vegetable substrates are simpler, more cost-effective, and pose less of a
risk to human health than microbes. Plants are the most desirable source for
the synthesis of NPs because they lead to production on a large scale as well
as creation of NPs that are stable and variable in form and size[31]”.
The green synthesis of ZnO-NPs, which
makes use of plant materials such as leaves or flowers, is often sterilised by
employing double-distilled water after being completely washed in running tap
water. This is done before the ZnO-NPs are prepared for use ( some use Tween 20
to sterilise it). After that, the plant part is allowed to dry at room
temperature, and then it is pounded into a powder using a mortar and a pestle.
This completes the process. After that, the plant extract was made by
continually magnetically whirling the combination while mixing the powder that
had been previously weighed with water that had been distilled [32]. This was
done while the mixture was being produced. “The solution is filtered using
whatman paper in order to make a clear solution that can be used as a plant
extract in the upcoming phase. This step is necessary in order to complete the
procedure. Zinc precursors such as zinc nitrate, zinc acetate, zinc sulphate,
or zinc chloride solution are coupled with a certain proportion of plant
extract. After a certain amount of time has elapsed, the mixture is put through
a calcination process that takes place at a higher temperature, which
eventually leads to the production of ZnO NPs”. Visual confirmation of the
created ZnO-NPs was achieved by noticing a change in colour, and UV-vis
spectroscopy was utilised for additional confirmation of the results of the
visual confirmation. Table 1 provides a breakdown and summary of the many
different types of plant materials that are used in the production of zinc
oxide nanoparticles.
Biopolymer Mediated Synthesis of
ZnO-NPs
A method that is beneficial to both
the economy and the natural world is one that uses natural polymers in the
manufacture of nanoparticles. This method is also environmentally friendly.
Natural polymers have been included into the manufacturing of a variety of
nanomaterials due to the positive impact that they have on the surrounding
ecosystem. Chitosan (CS) is one of the promising natural biopolymers that has
adapted with favourable features of biocompatibility, biodegradability,
non-hazardous, odourlessness, and metal ion adsorption. These qualities make
chitosan one of the most attractive natural biopolymers. The component of
crustacean shells known as chitin is the starting point for the production of
chitosan. The main amine and hydroxyl groups of chitosan have a very
substantial attraction (akin to that of a chelating agent) to metal ions, which
helps to reduce particle size and avoid agglomeration. Chitosan is derived from
crustacean shells and is derived from the chitin protein. The culture of the yeast-like
fungus Aureobasidium pullulans is required in order to manufacture the
biopolymer known as pullulan from starch. Pullulan is one of several types of
biopolymers. Pullulan has the property of being water soluble, which is a big
advantage. This makes pullulan a desirable substance. Pullulan may be utilised
without risk, does not result in the development of mutations, is odourless, is
biocompatible, and breaks down in a natural way [34, 35]. In addition,
tragacanth gum, often known as TG, is a natural polymer that does not cause
toxicity and is compatible with living organisms. Because of its consistency
throughout a wide pH and temperature range, it finds widespread application as
an emulsifier and thickening agent in the food and pharmaceutical industries.
In one of the studies, the gum was put to use in making nanoparticles of zinc
oxide. In one study, the gum was utilised as a polymer that was both kind to
the environment and economical. They were able to synthesise hexagonal zinc
oxide with a length of 240 nm and an average diameter ranging from 55–80 nm.
This was a successful endeavour. In addition, alginate is a naturally occurring
polyanionic polysaccharide that is produced by brown sea algae and is separated
for commercial usage from those algae. Alginate is used in a variety of
applications, including wound healing, cosmetics, and pharmaceuticals
(Phaeophyceae). According to the conclusions of a large number of studies, it
has been adopted in the field of green stabilisation due to the fact that it is
inexpensive, readily available, biocompatible, and kind to the environment. In
addition, carrageenan is a polymer that is derived from a kind of red seaweed
in a way that is not harmful to the surrounding ecosystem when it is
manufactured. It is generally agreed upon that carrageenan is capable of a wide
range of positive biological activities. This is largely because “to the
exceptional gelling and high viscosity properties that the native carrageenan
exhibits. Biopolymers possess a wide range of biological properties, some of
which include antiviral activity, anticoagulant activity, antitumor activity,
antioxidant activity, anti-inflammatory activity, and immunomodulatory
activity. All of these activities have the potential to bring about additional
benefits when applied in the context of medical application”.
Biomedical Applications
The recent development of
“nanotechnology and ZnO-NPs has led to major improvements in the biomedical
applications of nanomaterials. These advancements have been brought about as a
result. Better biocompatibility and responses for the interactions of ZnO-NPs
with biological tissue were achieved through the use of natural raw “materials
and living organisms as capping and reducing” agents in the synthesis of
ZnO-NPs”. This resulted in a significant improvement in the performance of the
ZnO-NPs. As a consequence of this, green synthesised ZnO-NPs have gained a
reputation for being effective nanomaterials “that can be used to target
bacterial infections, destroy the membrane of cancerous cells, deliver a
variety of compounds to diseased tissue, and measure the concentrations of
various biomarkers within the body. Because there is a large body of published
research on the several ways in which ZnO-NPs may be utilised in the fields of
biology and medicine, Fig. 1 is a representation of these various biomedical
applications, which are explained in more detail below[36] [37]”.
Figure 1. Possible
uses of green produced zinc oxide nanoparticles in the medical field[38]
Antibacterial Activity
Infectious illnesses caused by
bacteria provide significant dangers to the overall human population's health.
The susceptibility of individual cells within populations of harmful bacteria
to antibiotics has been steadily decreasing over the course of several decades.
This trend is connected to slower metabolic rates. In addition, because
antibiotic resistance is increasing at an alarming rate, bacterial illnesses
that were formerly simple to treat are increasingly becoming untreatable. The
researchers hoped that the appearance of new strains would help them solve this
complicated dilemma. Because of ZnO-NPs' one-of-a-kind qualities, such as a
large surface area and the capacity to create oxidative stress, research into
their potential use as an antibacterial agent has been considerable. ZnO-NPs
are responsible for the release of “Zn+2 ions, which have a reaction with the
thiol functional group found in respiratory enzymes. ZnO-NPs have an effect on
the cell membrane and result in the generation of reactive oxygen species
(ROS), which can include hydrogen peroxides, superoxide anion, and hydroxyl
radicals. It is possible that it might cause the membranes of bacterial cells
to disintegrate, causing damage to the DNA, the mitochondria, and the protein
membranes. This would ultimately lead to the death of the bacterial cells. The
antibacterial method that ZnO-NPs employ is depicted in the following figure,
Fig.2[39]”.
A large number of studies have looked
into the antibacterial potential of biosynthesized ZnO NPs against a wide
variety of bacteria, and they have shown that these NPs have a remarkable
antimicrobial effectiveness. “For instance, the antibacterial activity of P.
granatum/ZnO-NPs were investigated and compared against Escherichia coli (E.
coli) and Enterococcus faecalis (E. faecalis). The findings that were obtained
indicated that P. granatum/ZnO-NPs with smaller sizes are more efficient in
preventing the growth of both bacteria by having lower MIC50 values. E. coli
and B. subtilis were used as test organisms in another investigation, which
investigated the antibacterial activity of ZnO-NPs using the well diffusion
method. This study also reported on the antibacterial activity of ZnO-NPs.
According to the findings, the zone of inhibition against E. coli was
significantly bigger than that against B. subtilis at a concentration of 100
lg/ml, reaching a height of 12 millimetres[40]”. “In addition, the
antibacterial activity of the biosynthesized ZnO NPs utilising B. tomentosa
leaf extract was examined using B. subtilis, S. aureus, P. aeruginosa, and E.
coli as test organisms. Because of the differences in the structural
composition of Gram-positive and Gram-negative bacteria, ZnO NPs were found to
have a greater bactericidal effect on Gram-negative bacteria than on
Gram-positive bacteria [35]. This finding was based on the fact that
Gram-negative bacteria are more resistant to ZnO NPs. The ZnO NPs that were
produced from the B. tomentosa leaf extract showed a considerable zone of
inhibition for P. aeruginosa (20.3 mm) and E. coli (19.8 mm), whereas the zone
of inhibition was discovered to be smaller for B. subtilis (8.1 mm) and S.
aureus (10.7 mm)”.
Figure 2. Schematic illustration of
antibacterial mechanism of zinc oxide nanomaterials[41].
Anticancer Activity
Cancer may be a collection of
diseases that are characterised by the abnormal development of tissue, which
may result in the development of tumours. Tumors have the potential to “spread
into other tissues and cause extreme impacts on the patient, with complications
and severe effects possibly leading to death. In 2019” diseases were ranked as
the following leading cause of mortality in the United States, with around 2
million people being examined each year. The treatments that are now available,
such as chemotherapy and radiation, are helpful; nevertheless, they are not
completely viable and have a number of significant drawbacks. These drawbacks
include substantial side effects such as immunosuppression, anaemia, illness,
and even death. Indeed, it has been pointed out in the scientific literature
that some cancer cells have developed the ability to withstand treatment, which
has led to the appearance of chemotherapy-resistant tumours and eliminates the
possibility of using those medicines as a treatment option for certain kinds of
patients[18]. As a direct consequence of this, significant efforts have been
put into the creation of new methods. As a result, the use of nanotechnology
has grown in popularity as a result of the fact that it has a tendency to be
utilised towards cancer therapy and overcomes significant drawbacks (of the
conventional treatment techniques) without causing harm to normal tissues. In
addition to its usage in a variety of other biomedical applications, ZnO-NPs
have also been investigated for their potential “as biocompatible and
biodegradable nanoplatforms for the treatment of cancer. ZnO-NPs are known to
trigger the creation of ROS upon contact with cells, which leads to
mitochondrial damage and activates cell death in cancer tissue”. This occurs
because ROS are generated when ZnO-NPs come into contact with cells.
ZnO nanoparticles that were made
using environmentally friendly synthesis methods have had their potential to
fight cancer tested against a number of different cancer cell types. For
instance, the anticancer activity of the produced nanomaterials was tested on
A549 lung cancer cells, and the results showed that the inhibitory
concentration (IC50) of the nanomaterials was 15.6 lg/ml. The MTT test that was
utilised for the purpose of cytotoxicity evaluation also shown that ZnO NPs had
a strong dose-dependent cytotoxic impact “against the A549 lung cancer cell
line. In addition, the potential anticancer activity of the produced
ZnO-curcumin nanocomposites” was investigated using the MTT assay on the
rhabdomyosarcoma RD cell line, and their cytotoxic effects were investigated
using the resazurin assay on human embryonic kidney cells. The findings
demonstrated the optimal equilibrium between the two, exhibiting the least
amount of toxicity against healthy cells while yet demonstrating effective
anticancer action. Another study came to the same conclusion, stating “that
ZnO-NPs produced using the Deverra tortuosa plant showed a profound selective
cytotoxic effect on the Caco-2 and A549 cancer cell lines” whereas the ZnO-NPs
produced using normal WI38 cells showed an appreciably lower level of cytotoxic
activity. Caco-2 was a more sensitive cell line than A549, and it was notable
that ZnO-NPs exhibited the most effective cytotoxic action. This study also
revealed that much higher IC50 values were obtained from the treatment of the
normal lung epithelial cell (WI38) with the respective ZnO-NPs. These values
were 902.83 and 434.60 g/ml, respectively. ZnO-NPs, with all of their promising
properties, provide a pleasing alternative to standard therapeutic methods that
are both safer and more cost-effective.
Antifungal Activity
“ZnO-NPs have an antibacterial
capability that is not just applicable to microbes or bacteria, but also to
other types of microorganisms, such as fungus. Because of its widespread use in
the food industry as an antifungal additive, several publications on its
antifungal activity are available for the treatment of yeasts and fungi”. These
findings include a variety of antifungal treatments. The proliferation of
fungal infections is one of the most significant problems facing agriculture
today, and it results in significant monetary losses for farmers. ZnO-NPs have
been shown to be effective antifungal agents against plant diseases by a number
of different research groups. For instance, nanomaterials were evaluated for
their effectiveness in combating fungal phytopathogens such as A. alternata, A.
niger, B. cinerea, F. oxysporum, and P. expansum. Antifungal activity was
demonstrated by the nanomaterials that were employed in the investigation. The
inhibitive effects of fungicides were significantly improved by the use of
nanomaterials. It was discovered that P. expansum was the most sensitive of all
the fungi. In addition, the synthesised ZnO-NPs have shown to have an effective
antifungal effect against C. albicans, with a minimum inhibitory concentration
(MIC) of 128 g/ml and a minimum fungicidal concentration (MFC) of 256 g/ml,
respectively. These concentrations are referred to as the minimum inhibitory
concentration and minimum fungicidal concentration, respectively. By using a
well dispersion method, we were also able to investigate the antifungal effect
of ZnO NPs against Aspergillus and Penicillium. At a concentration of 30 g/mL,
the antifungal activity demonstrated that ZnO-NPs are an efficient fungicidal
agent against both Aspergillus (4 mm 0.5 mm) and Penicillium (3 mm 0.4 mm).
According to the findings of another investigation, MICs were determined to be
the lowest concentration of nanoparticle that resulted in a growth inhibition
of Candida isolates that was at least 90 percent lower than the levels of
growth seen in the control group (wells without ZnO NPs). It was determined
that the minimum fungicidal concentration for ZnO NPs was the lowest
concentration at which yeast cell development could be suppressed by more than
99.9 percent (MFC).
Anti-inflammatory Activity
An damage of any kind will cause live
tissue to go into an excessive reactive reaction known as inflammation. The
most prominent symptoms of inflammation are redness, discomfort, heat, and
swelling in the affected area. The complicated organic reaction of bodily
tissues to harmful stimuli, such as infections, damaged cells, or irritants, is
known as inflammation. Inflammation is required for the proper functioning of
this response. When there is damage to any portion of the body, the arterioles
that are located in the surrounding tissue will enlarge. Because of the
increased blood circulation toward the location, this causes the skin to become
red. There is a distinction between acute inflammation and chronic
inflammation. Acute inflammation might be the body's first response to noxious
stimuli once it has been exposed to them. When someone has chronic
inflammation, their body's natural inflammatory response may become
exaggerated, which can cause long-term damage to their health. The
anti-inflammatory benefits of ZnO-NPs have garnered a lot of attention ever
since the invention of nanomaterials, especially when taken into consideration
with these biological uses of zinc ions.
“Inhibition of pro-inflammatory
cytokine release, inhibition of myeloperoxidase, inhibition of inducible nitric
oxide synthase (iNOS) enzyme expression, inhibition of the NF-jb pathway, and
inhibition of mast cell degranulation are some of the mechanisms through which
ZnO NPs exert their anti-inflammatory activity. Tabular representation of the
anti-inflammatory effects of green-synthesized zinc oxide nanoparticles (ZnO
NPs)”.
In 2016, an in vivo study of the
efficacy "of ZnO-NPs for wound healing was undertaken by administering a
matrix containing EPCs topically to wounds that were present in mice. This
evaluation was done to determine whether or not ZnO-NPs are effective in
promoting wound healing. It was demonstrated through in vivo testing on a mouse
model that a GPZ scaffold that had been enriched with EPCs promoted
considerably speedier "wound" healing than any of the other groups.
This was the case regardless of whatever group they were compared to. The
ability of chitosan/poly(vinyl alcohol)/zinc oxide (CS/PVA/ZnO) beads to
promote wound healing in mice was investigated in a research that was carried
out not too long ago. In vivo testing on the skin of mice revealed that wounds
treated with CS/PVA/ZnO dressings seemed to heal more quickly and completely
than those treated with pure chitosan and CS/PVA. In addition to this, a study
was conducted to examine the effects of ZnO-NPs on the rate of proliferation of
fibroblast cells (NIH3T3) as a wound healing activity. According to the
findings, utilising ZnO nanomaterials with a larger particle size results in a
considerable rise in the rate of fibroblast cell proliferation. ZnO-NP/silica
gel (ZnO-NP/SG) dressings were utilised in another experiment, which indicated
the healing efficiency of ZnO-NP/SG dressings on mouse wounds. This was made
possible because to the extensive evidence on the healing property of
ZnO-NP/silica gel (ZnO-NP/SG) dressings. Animals whose skin was treated with
ZnO-NP/SG-30 ppm had a maximum wound reduction of 95% when compared to
untreated mice. According to these findings, ZnO-NPs increased skin mending on
the wound surface, which gives credibility to its possible application in the
future.
Table
2. Anti-inflammatory activity of ZnO nanomaterials[41].
CONCLUSION
An intriguing area of study within
nanoscience is the environmentally friendly manufacturing of metal
nanoparticles. The biosynthesis of metal nanoparticles utilising plants as the
starting material for large-scale biosynthesis is another recent topic of attention.
When compared to those generated by other creatures, the nanoparticles that are
created by plants are more stable and exhibit a greater variety in both their
structure and size. This article is a review that reports the production of ZnO
nanoparticles. Nanoparticles of zinc oxide offer a wide range of potential uses
across various industries. ZnO nanoparticles have an action that is
antibacterial, which deserves particular emphasis. The leaf of the coffee plant
was used to successfully create an environmentally friendly way of producing
ZnO nanoparticles. The biological synthesis approach that was taken was chosen
since it is gentle, rapidly biodegradable, and requires little time to prepare.
According to the findings of a number of research, it may be possible to
produce ZnONPs using an environmentally friendly synthesis method that makes
use of a wide variety of plants, fungi, bacteria, and algae. In addition, the
research that were described here suggest that regardless of their origin,
these substrates perform the functions of reducing agents, stabilisers, or
chelating chemicals. It is noteworthy to note that the final characteristics of
the produced nanoparticles are considerably affected by parameters such as
conditions of temperature, duration of reaction, pH, and concentrations, in
addition to the differences in composition observed in biological extracts.
Among these characteristics, the concentrations of both the biological extract
and the zinc supply, as well as the pH of the solution, have a significant
impact in determining the final properties of ZnONPs generated through the use
of the green method. This is supported by the research that has been
referenced.
Conflict
of interest:
Authors
declares no conflicts of interest.