Green Synthesis And Characterization Of Silver Nano Particles
From Leaf Aqueous Extract Of Aloe vera (L.) Burm. And Its Anti
Microbial Activity
Dr. S. Ananthalakshmi1, R.Kavitha2 ,S.Kalaivani2 , J. Emili
Saranya2
1. Research Advisor, 2. Research Scholar, Department of
Chemistry,
Urumu Dhanalakshmi College, Tiruchirappalli-19, Tamilnadu,
India.
[email protected] , [email protected].
ABSTRACT
Silver nano particles were synthesized using extract of Aloe
vera (L.) Burm. which has been proven active against
micro-organisms. Characterization was done by using Ultra-Visible
(UV- Vis) spectrophotometer, Scanning Electron Microscopy (SEM),
FT-IR and antimicrobial activity. SEM showed the formation of
silver nano particles with an average size of 400 nm. It can be
concluded that the gel of Aloe vera (L.) Burm can be good source
for synthesis of nano particles of better antimicrobial activity
against microorganisms. The important outcome found in the study is
the development of value added products front medicinal plant Aloe
vera (L.) Burm for biomedical and nano particles based
industries.
KEYWORDS: Silver Nano Particles, Green Synthesis, Aloe vera (L.)
Burm, Anti microbial Activity.
INTRODUCTION
Nanotechnology can be termed as the fabrication,
characterization, exploration and application of nanosized (1-100
nm) materials for the development of science. It deals with the
study of extremely minute structures and the prefix “nano” is a
Greek word which means “dwarf or miniature”. Nanotechnology
provides the ability to engineer the properties of materials by
controlling their size, and this has been driven research towards a
multitude of potential uses for nanomaterials. Nanotechnology has
been spread to number of areas including biomedical services,
cosmetics, drug gene delivery, environmental health, food, health
care, catalysis, mechanics, non linear optical devices, optics,
photo-electrochemical application, single electron transistors, and
space industries.
The Nanoparticles (NPs) received a particular attention for
their positive impact in improving many sectors of economy,
including consumer products, pharmaceutics, cosmetics,
transportation, energy and agriculture etc., and are being
increasingly produced for a wide range of new applications within
industry are emerging rapidly. A very interesting application of
NPs in the scope of life sciences is their use as ‘smart’ delivery
system. Metal NPs are of great scientific interest as they bridge
the gap between the bulk and atomic structures. NPs have unique
physicochemical properties, like., high surface area, high
reactivity, tunable pore size and particle morphology. Recent
advances in nanotechnology include the incorporation of metallic
NPs into diverse industrial, medical, and household products.
Silver is of great choice in the field of biological systems,
living organisms and medicine among the various noble metals.
Silver has been not only proven as an effective tool for retarding
and preventing the bacterial infections but also they are found to
exhibit wound healing activity. Colloidal silver nanoparticles
(AgNPs) exhibits distinct properties such as catalytic,
antibacterial, good conductivity and chemical stability. The
investigations on AgNPs have attained significance due to their use
in opto-electronics systems. Anti-microbial activity and
silver-embedded fabrics used in sporting equipment. However, still
there is a need for economical, commercially viable as well as
environmentally clean route of synthesis for AgNPs.
A number of physical and chemical approaches are explored for
the preparation of nanoparticles. Physical method involves laser
ablation and evaporation condensation methods whereas in chemical
method utilizes chemical reductants (NaBH4, ethanol, ethylene
glycol etc.), aerosol technique, electrochemical or sonochemical
deposition, photochemical reduction and laser irradiation
technique. Although in the chemical synthesis of NPs, generation of
hazardous by products is highlighted as the environmental
contaminants as well as involvement of certain chemicals is
expensive and may lead to the presence of noxious chemical species
tangled on the surface of NPs, which may have adversarial effect on
environment.
Recent developments in plant tissue culture techniques in
fabrication of NPs have shown promising results to improve the
productivity to many folds. As plants potentially eliminate the
environmental issues by making the NPs more biocompatible, it is
necessary to increase the efficiency of the locally available and
unexplored plants resources for the green synthesis of AgNPs and
clarifies the possible mechanism involved in synthesis, is still
infancy. The silver nanoparticles have wide spread antimicrobial
resistance in biological process [1-11].
Chemicals used for nanoparticles synthesis and stabilization are
toxic and lead to non-eco-friendly by products. Thus, there is an
increasing demand for green nanotechnology [12]. Many biological
approaches for both extracellular and intracellular nanoparticles
synthesis have been reported till date using microorganisms
including bacteria, fungi and plant materials [13, 14].
In the recent days, silver nanoparticle have been synthesized
from the naturally occurring sources and their products like green
tea (Camellia sinensis), Neem (Azadirachtaindica), leguminous shrub
(Sesbaniadrummondii), various leaf broth, natural rubber, starch,
lemongrass leaves extract Aloe vera plant extract etc., [15].
Aloe vera is a shrubby, perennial succulent plant of Liliaceae
family having turgid leaves joined at the stem in a rosette
pattern. Plant is also characterized by stemless large, thick,
fleshy leaves having a sharp apex and a spiny margin [16]. Aloe
vera has been shown to have anti-inflammatory, immuno stimulatory
and cell growth stimulatory activities [17-19]. Activity against a
variety of infectious agents in terms of anti-viral, anti-fungal
and anti-bacterial has been also reported [20-22]. Since early
times, Aloe vera gel has been used for the treatment of several
skin cuts and burn abnormalities too [23].
Nano crystalline silver particles have found tremendous
applications in the field of biomedical and this was the main route
to carried out our present study. Antimicrobial properties of
silver nanoparticles caused the use of the nano metal in different
field of medicine, various industry, and health. Hence we aimed to;
Synthesize silver nanoparticles, characterize them by the UV
visible spectrum, FT-IR, Scanning Electron Microscopy techniques
and to study the antimicrobial activity of the synthesised
compounds. Due to the development of new material for biomedical
and nanoparticles based industries, plant mediated synthesis of
silver nanoparticles have more advantageous and shows best
antimicrobial activities, we aimed to study anti-microbial
activities of the synthesized Silver nanoparticles using Aloe Vera
(L.) Burm. extract.
METHODS AND MATERIALS
Preparation of Aloe vera (L.) Burm. extract
The collected Aloe vera (L.) Burm. plant was washed thoroughly
with running tap water for 5 minutes to remove dust and then it was
washed with deionized water. Aloe vera (L.) Burm. gel was pulped
out from the Aloe vera (L.) Burm. plant and washed for 5 minutes
with deionized water. These gel was crushed properly and filtrated
using filter paper (pore size 25. M). The filtered Aloe vera (L.)
Burm. extract was collected and stored for the preparation of
silver nanoparticles.
Preparation of silver nanoparticles
Aloe vera (L.) Burm. extract and silver nitrate solution in a
specified quantitative were used to prepare silver nanoparticles
and the colour was noted. Initially 5ml of Aloe vera (L.) Burm.
extract was taken in a 50 ml beaker and 10 ml of 0.1N silver
nitrate solution was slowly added with constant stirring using
mechanical stirrer and we’re heated approximately to 90 ˚C for 45
minutes. The brownish black solution formed were collected and
cooled for 20 minutes. Under the solution there was the formation
of brownish black precipitate obtained which was a silver
nanoparticles and the solution was decayed slowly and the residue
were kept to dry without disturbing.
The supernatant liquid was centrifuged at 10000 rpm for 30
minutes to isolate the silver nanoparticles from plant materials
and other compound present in the solution. The residue was
collected, washed three times with deionized water and dried and
the residues were used for the further analysis. The Table (I and
II) indicates the different ml used to prepare the silver
nanoparticles.
Table – I Equal quantity of Aloe vera (L.) Burm. and 0.1N AgNO3
solution studied.
0.1N AgNO3 (ml)
Aloe vera (L.) Burm. extract (ml)
10
10
15
10
20
10
Table – II Variable quantity of Aloe vera (L.) Burm. and 0.1N
AgNO3 solution studied.
0.1N AgNO3 (ml)
Aloe vera (L.) Burm. extract (ml)
10
5
10
10
10
15
Fig. 1. Photograph of the plant Aloe vera (L.) Burm.
The above same procedure was followed for the preparation of
silver nanoparticles for different ratio mixtures and the colour of
the solution were noted. The dried silver nanoparticles were
characterized by UV, FT-IR and SEM. UV-Visible spectrometry was
used to identify, characterize and analyse the silver absorption.
Scanning electron microscopy (SEM) was used to find out the surface
and morphological characterisation at nanometer of Synthesised Ag
nanoparticles. Fourier transformed Infrared spectroscopy (FT-IR)
was used to identify the organic functional group and determined
which of them are attached to Ag nanoparticle’s surface. And
finally the antimicrobial activities of silver nanoparticles was
studied.
MICRO ORGANISMS AND CULTURE MEDIA
Bacterial cultures such as, Staphylococcus aureus, Bacillus
subtilis, E.coli, Psudomonas ,A.niger and Candida albicans were
obtained from Eumic Analytical Lab and Research Institute,
Tiruchirappalli. Bacterial strains were maintained on Nutrient agar
slants (Hi media) at 4˚C.
INOCULUM PREPARATION
Bacterial cultures were subcultured in liquid medium (Nutrient
broth) at 37˚C for 8hrs and further used for the test (105-106
CFU/ml). These suspensions were prepared immediately before the
test was carried out.
PREPARATION OF CULTURE MEDIA
NUTRIENT AGAR MEDIUM
Nutrient agar medium is one of the most commonly used medium for
several routine bacteriological purposes:
Ingredients Grams/Litre
Peptone:5gm
Beef extract:3gm
Agar:15gm
Sodium chloride:5gm
Yeast extract:1.5gm
pH:7.0
After adding all the ingredients into the distilled water it was
boiled and dissolved the medium completely and sterilized by
autoclaving at 15 psi pressure (121˚C) for 15 minutes.
NUTRIENT BROTH
The nutrient broth was prepared by the same composition without
agar. After adding all the ingredients into the distilled water it
was boiled to dissolve the medium completely and sterilized by
autoclaving at 15 psi pressure (121˚C) for 15 minutes.
PREPARATION OF PLANT MATERIAL
Leaves, of the plant materials taken for this study were shade
dried individually at room temperature and then powdered by using
electric, blender. About 10gm of fresh plant materials (Leaves)
were extracted with 100ml of distilled water 90:10. They were kept
for seven days at room temperature (31˚C) for complete extraction.
After seven days the extracts were filtered through What man no.1
filter paper. This extract was collected and kept in
refrigerator.
ASSAY OF ANTIMICROBIAL ACTIVITY
MICROBIAL INOCULUM PREPARATION
The nutrient broth were prepared, then identified bacterial
colonies were inoculated into the broth culture were used for
antimicrobial activity.
KIRBY BAUER AGAR WELL DIFFUSION ASSAY
The nutrient agar medium was prepared and sterilized by
autoclaving at 121˚C 15 psi pressure for 15 minutes then
aseptically poured the medium into the sterile petriplates and
allowed to solidify the Bacterial broth culture was swabbed on each
petriplates using a sterile buds. Then wells were made by well
cutter. The organic solvent extracts of leaves were added to each
well aseptically.
This procedure was repeated for each Petri plates then the
petriplates were incubated at 37˚C for 24 hrs. After incubation the
plates were observed for the zone of inhibition.
RESULTS AND DISCUSSION
The present investigation entitled “Green synthesis of silver
nanoparticles using Aloe vera (L.) Burm. extract and its
characterization and antimicrobial activity” was conducted to study
the green synthesis of AgNPs by reduction of aqueous silver ions
using selected plant extract and the effect of different reaction
conditions were studied. The outcomes during the course of
investigation have been portrayed in different Tables and Figures
and are described Effect of different physical appearance on the
green synthesis of silver nanoparticles
Initially Aloe vera (L.) Burm. plant were screened for the green
synthesis of AgNPs. The synthesis of silver nanoparticles was
monitored by colour change of the plant extract after the bio
reduction of silver nitrate. The formation of silver nanoparticles
was confirmed by changing in the solution colour from pale yellow
to dark brown.
Fig.2 Pale yellow colour of the Aloe vera (L.) Burm. extract
Fig.3 50 ml beaker shows the colour of the Aloe vera (L.) Burm
extract after mixed with 0.1N silver nitrate solution and heated
standard flask shows the colour of 0.1N silver nitrate
solution.
Fig.4 Colour of the solution after mixing of 0.1N silver nitrate
solution and Aloevera (L.) Burm. extract before heating and stirrin
g
Fig.5. Dark brownish colour solution of silver nanoparticles
obtained after the heating along with mechanical stirrer
Fig.6. Silver nanoparticles after dried
UV-VISIBLE spectrum of silver nitrate solution in Aloe vera (L.)
Burm. extract
UV-VISIBLE spectrum of reaction medium confirmed the presence of
Ag nanoparticles. The characteristic absorption peaks of 0.1N
silver nitrate solution in Aloe vera (L.) Burm. recorded which
indicates the absorption of silver.
To confirm the formation and stability of synthesis nanoparticle
were assayed by UV-Viable spectrophotometer, Fig.7 shows the
UV-Visible spectra of AgNO3 (10-3M). As shown in figure 7, UV
–vis spectra showed that in the range of low amounts of the extract
the absorption spectra exhibit a gradual increase of the absorbance
accompanied with a shift in the λmax of SPR band absorption peak
from 250 to 280 nm. Further increasing the concentration of plant
extract with constant amount of AgNO3, the λmax was shifted to
longer wavelengths. The inset UV-vis spectrum was related
to the Ag ions before the bio-reduction event, in which an
absorption band appeared at 300 nm. The appearance of the band at
410 nm, along with absence of 300 nm absorption band indicate of
the successful synthesis of AgNPs under experimental conditions.
Such a characteristic Surface Plasmoon Resanance (SPR) peak for
AgNPs has been reported to predominantly appear in the range of
300-500 nm.
In fig 7 the absorption peak of 300 nm shows the presence of
metal Ag. In fig 8 there is no any absorption peak noted in the UV-
visible spectrum of Aloe vera (L.) Burm. which indicates the
absence of any metal atom in the extract.
But, in the fig 9 of UV-visible spectrum of Aloe vera (L.) Burm.
and AgNO3 solution, the absorption peak is shifted to 410 nm with a
broad absorption peak confirms the formation of nanoparticle in the
Aloe vera (L.) Burm. AgNO3 solutions.
Fig.7. UV-Visible spectrum of 0.1N silver nitrate solution
Fig.8.. UV-Visible spectrum of Aloe vera (L.) Burm.
Fig.9. UV-VISIBLE spectrum of silver nitrate solution in Aloe
vera (L.) Burm.
FT-IR ANALYSIS
FT-IR spectrum was used to identify the possible functional
group of biomolecules in the plant extract that might be
responsible for the bio-reduction and coating of AgNPs. FT-IR
measurements were carried out to identify the biomolecules for
capping and efficient stabilization of the metal nanoparticles
synthesized.
The FT-IR spectrum of silver nanoparticles (Figure 10) showed
the band between 3417cm-1corresponds to O-H group in the
biomolecules. The IR bands at 2926 and 2855.21 cm-1 due to C-H
stretching vibration modes in hydrocarbon chains. In the case of
AgNPs, a large shift in the absorbance peak with decreased band
intensity was observed at 1384.63cm-1.
The spectra also illustrate prominent shift in the wave numbers
corresponding to amide (1652.5 – 1600 cm-1), and the peak at
1628.33 cm-1 indicates the presence of free amino group which may
be interacted with AgNPs surface maintain the stability of
nanoparticles. The FT-IR Spectrum in Figure.10 indicates the
capping of the nanoparticles with the extract constituents.
Fig.10. FT-IR of green synthesized silver Nano particle.
SEM analysis
SEM image shows the morphological character, size and surface of
the AgNPs synthesized by the extract of Aloe vera (L.) Burm. under
optimized physical conditions. SEM microscopy which revealed that
the AgNPs are around 200 nm in size with the mixture of many shapes
i.e. triangle, rhombus, and spherical are clearly observed and
spherical are predominant. SEM determination showed the formation
of AgNPs, which were well dispersed and the aggregation of the
particles could be seen. The corresponding SEM micrographs being
obtained at an accelerating voltage of 10 kv at various
magnifications. At such magnification, the green synthesized silver
nanoparticles showed rough areas on which micro pores and macro
pores were clearly identifiable. In the image, the particle sizes
range from 89.06 nm to 89.22 nm is obtained. The Figures (11 &
12) show that the particles are highly crystalline in nature.
Fig.11 Fig.12
Fig.11 & 12. SEM image of AgNP under different magnification
and obtained from the extract of Aloe vera (L.) Burm.
Antimicrobial activities of silver nanoparticles
The green synthesized silver nanoparticles are tested for its
antimicrobial activity towards the micro organism. Silver
nanoparticles were divided and prepared in four different
concentration of 25µl, 50µl, 75µl, 100µl and these are correlated
with the controlled medium. The synthesized silver nanoparticles is
active against the gram positive bacteria, gram negative bacteria
and fungal which is listed in Table III.
Antimicrobial activity assay of the synthesized AgNps,
nanoparticles was studied against the growth of Gram Positive
bacteria (Bacillus subtiles and Staphylococcus aureus), Gram
negative bacteria (E. coli , and Pseudomonas aeruginosa)
and Fungi (Candida albicansand A.niger) using the standard agar
well diffusion technique. The results are illustrated in Fig.13 -18
and Table III.
The mean zone of inhibition produced by the AgNPs against tested
bacterial and fungal strains ranged from 7 mm to 16 mm under the
control of Gentamicin antibiotic disc. The organisms used are very
sensitive to standard antibiotic Gentamicin and have registered the
zone of inhibition 15, 25, 20, 15, 15 and 15 mm respectively (Table
-III and figures 13-18). The green synthesized silver nanoparticles
has produced zone inhibition range from16-23 (mm/ml) against
Bacillus subtilis, 18 -24 (mm/ml) against Staphylococcus aureus, 20
– 28 (mm/ml) against E.coli 18 -24 (mm/ml) against Pseudomonas, 22
– 30 (mm/ml) Candida albicans, 22- 32 (mm/ml) against A.niger.
The zone of inhibition values show that antimicrobial activity
of the green synthesised silver nanoparticles is in a dose
dependent manner. This may be due to the presence of antimicrobial
compound in the nano particles. Thus, this result shows that Silver
nanoparticles could also be useful as the antibiotics.
Table III Antimicrobial evaluation data of the Silver
nanoparticles.
SAMPLE
DMSO Extract 100 µl added and Zone of inhibition (mm/ml)
25 µl
50 µl
75 µl
100 µl
Control
Bacillus subtilis
16
18
20
23
15
Staphylococcus aureus
18
20
22
24
25
E.coli
20
22
25
28
20
Pseudomonas
18
20
21
24
15
Candida albicans
22
24
27
30
15
A.niger
22
24
28
32
15
CONTROL: Gentamicin antibiotic disc
The above characterization of green synthesized silver
nanoparticles has shows the antimicrobial activities which can be
applicable in the field of biomedical and nanotechnology
industries. The following images show the antimicrobial activities
towards the microorganisms.
Fig.13. Zone inhibition of the green synthesized silver
nanoparticles against Bacillus subtilis
Fig.14. Zone inhibition of the green synthesized silver
nanoparticles against Staphylococcus aureus
Fig.15. Zone inhibition of the green synthesized silver
nanoparticles against E.coli.
Fig.15. Zone inhibition of the green synthesized silver
nanoparticles against E.coli.
Fig.17. Zone inhibition of the green synthesized silver
nanoparticles against Candida albicans
Fig.18. Zone inhibition of the green synthesized silver
nanoparticles against A.niger.
CONCLUSION
In the present study we focused on green synthesis of silver
nanoparticles using Aloe vera ( L.) Burm. extract. Further, these
synthesized silver nanoparticles are characterised using UV-
Visible technique. The morphology and particle size are determined
by SEM analysis. The primary confirmatory for the silver
nanoparticles was colour change in UV- Visible. Absorption spectra
of silver nanoparticles showed the peak shifted to approximately
410 nm with a broad absorption peak. SEM analysis confirms that the
particles are in the range from 89.05 nm –89.22 nm. FT-IR analysis
also been discussed. Based on the measured zone of inhibition
values it is observed that the silver nanoparticles shows the
antimicrobial activity. Therefore, the green synthesized silver
nanoparticles can be promising candidate for pharmaceutical,
biomedical and environmental applications.
REFERENCES
1. Harekrishna Bar, D.K.B., Gobindasahoo P, priyanka Sarkar,
Sankar PD., "Green synthesis of silvernanoparticles using latex of
Jatropha curcas." Colliod surface A, 2009. 39(3): p. 134-139.
2. Cassandra D, N.N., Jodi H, Linfeng G, Tan, Li, et al., "Green
synthesis of gold and silver nanoparticles from plant
extracts.".
3. Kaviya S, S.J., Viswanathan B., "Green Synthesis of silver
nanoparticles using Polyalthialongifolia Leaf extract along with
D-Sorbitol.". Journal of nanotechnology, 2011: p. 1-5.
4. Catauro M, R.M., De Gaaetano FD, Marotta A, "Sol–gel
processing of drug delivery materials and release kinetics.". J
Mater Sci Mater Med, 2005. 16(3): p. 261-265.
5. Crabtree JH, B.R., Siddiqi Ra, Huen IT, Handott LL, Fishman
A, "The efficacy of silver-ion implanted catheters in reducing
peritoneal dialysis-related infections.". Perit Dial Int, 2003.
23(4): p. 368-374.
6. Krolikowska A, K.A., Michota A, Bukowska J, "SERS studies on
the structure of thioglycolic acid monolayers on silver and gold.".
Surf Sci, 2003. 532: p. 227-232.
7. Zhao G, S.J., "Multiple parameters for the
comprehensiveevaluation of the susceptibility of Escherichia coli
to the silver ion.". Biometals, 1998. 11: p. 27.
8. Jiang H, M.S., Wong ACL, Denes FS, "Plasma enhanced
deposition of silver nanoparticles onto polymer and metal surfaces
for the generation of antimicrobial characteristics." J
ApplPolymSci, 2004. 93: p. 1411-1422.
9. Duran N, M.P., Alves OL, De Souza GIH, Esposito E,
"Mechanistic aspects of biosynthesis of silver nanoparticles by
several Fusariumoxysporum strains." Nanobiotechnol, 2005. 3: p.
8-14.
10. RO, B., "Silver ions in the treatment of local infections.".
Met Based Drugs, 1999. 6: p. 297-300.
11. Klaus T, J.R., Olsson E, Granqvist C-G, "Silverbased
crystalline nanoparticles, microbially fabricated.". Proc Natl
AcadSci USA, 1999. 96: p. 13611-13614.
12. Garima Singhal , R.B., KunalKasariya , Ashish Ranjan Sharma
, Rajendra Pal Singh, "Biosynthesis of silver nanoparticles using
Ocimum sanctum (Tulsi) leaf extract and screening its antimicrobial
activity.". J Nanopart Res, 2011. 13: p. 2981-2988.
13. Mukherjee P, A.A., Mandal DS, Senapati S, Sainkar R, Khan
MI, Parishcha R, Ajaykumar PV, Alam M, Kumar R, Sastry M,
"Fungus-mediated synthesis of silver nanoparticles and their
immobilization in the mycelial matrix: a novel biological approach
to nanoparticle synthesis.". Nano Lett, 2001. 1: p. 515-519.
14. Spring H, S.K., "Diversity of magnetotactic bacteria.". Syst
Appl Microbiol, 1995. 18(2): p. 147-153.
15. Vijayaraghavan K, K.N.S., Udaya Prakash N, Madhankumar D.,
"Biomimetic synthesis of silver nanoparticles by aqueous extract of
Syzygiumaromaticum.". Colloids Surf B Biointerfaces, 2012. 75: p.
33-35.
16. Steenkamp V, Stewart MJ (2007) Medicinal applications and
toxicological
activities of Aloe products. Pharm Biol 45: 411-420.
17. Afzal M, Ali M, Hassan RA, Sweedan N, Dhami MS (1991)
Identification of
Some Prostanoids in Aloe vera Extracts. Planta Med 57:
38-40.
18. Ramamoorthy L, Tizard IR (1998) Induction of apoptosis in a
macrophage
cell line RAW 264.7 by acemannan, a beta-(1,4)-acetylated
mannan. Mol
Pharmacol 53: 415-421.
19. Tizard ID, Busbee B, Maxwell, Mc K (1994) Effect of
acemannan, a complex
carbohydrate, on wound healing in young and aged rats. Wounds 6:
201-209.
20. Kahlon JB, Kemp MC, Yawei N, Carpenter RH, Shannon WM, et
al. (1991) Invitro evaluation of the synergistic antiviral effects
of acemannan in combination with azidothymidine and acyclovir. Mol
Biother 3: 214-223.
21. Kawai K, Beppu H, Simpo K, Chihara T, Yamamoto N, et al.
(1998) In vivo effects of Aloe arborescens Miller var. natalensis
Berger (Kidachi aloe) on experimental Tinea pedis in guinea-pig
feet. Phytother Res 12: 178-182.
22. Kumar S, Budhwar L, Yadav A, Yadav M, Yadav JP (2016)
Phytochemical screening and antibacterial activity of Aloe vera
collected from different climatic regions of India. Nat Prod J 6:
73-82.
23. Heggie S, Bryant GP, Tripcony L, Keller J, Rose P, et al.
(2002) A Phase III study on the efficacy of topical Aloe vera gel
on irradiated breast tissue. Cancer
Nurs 25: 442-451.
24. Xu Z P, Z.Q.P., Lu G Q and Yu A B, “Inorganic Nanoparticles
As Carriers For Efficient Cellular Delivery”,. Chemical Engineering
Science, 2006. 61: p. 1027-1040.
25. Klaus, T.J., R.; Olsson, E. &Granqvist, C.Gr.,
"Silver-based crystalline nanoparticles, microbially fabricated.".
Proc Natl AcadSci USA,, 1999. 96: p. 13611-13614.
26. Senapati, S., "Biosynthesis and immobilization of
nanoparticles and their applications.". University of pune, India,
2005.
27. Kruis, F.F., H. &Rellinghaus, B., "Sintering and
evaporation characteristics of gas-phase synthesis of size-selected
PbS nanoparticles.". Mater SciEng B, 2000. 69: p. 329-324.
28. Magnusson, M.D., K.; Malm, J.; Bovin, J. & Samuelson,
L., "Gold nanoparticles: production, reshaping, and thermal
charging.". J Nanoparticle Res, 1999. 1: p. 243-251.
29. Jung, J.O., H.; Noh, H.; Ji, J. & Kim, S., "Metal
nanoparticle generation using a small ceramic heater with a local
heating area.". J Aerosol Sci, 2006. 37: p. 1662-1670.
30. Mafune, F.K., J.; Takeda, Y.; Kondow, T. &Sawabe, H.,
"Formation of gold nanoparticles by laser ablation in aqueous
solution of surfactant.". J PhysChem B, 2001. 105: p.
5114-5120.
31. Mafune, F.K., J.; Takeda, Y.; Kondow, T. &Sawabe, H.,
"Structure and stability of silver nanoparticles in aqueous
solution produced by laser ablation.". J Phys Chem B 2000. 104: p.
8333-8337.
32. Kabashin, A.V.M., M., "Synthesis of colloidal nanoparticles
during femtosecond laser ablation of gold in water.". J ApplPhys,
2003. 94: p. 7941-7943.
33. Dolgaev, S.I.S., A.V.; Voronov, V.V.; Shafeev, G.A.
&Bozon-Verduraz, F.,"Nanoparticles produced by laser ablation
of solids in liquid environment.". Appl Surf Science, 2002. 186: p.
546-551.
34. Sylvestre, J.P.K., A.V.; Sacher, E.; Meunier, M. &
Luong, J.H.T., "Stabilization and size control of gold
nanoparticles during laser ablation in aqueous cyclodextrins.". J
Am ChemSoc, 2004. 126: p. 7176-7177.
35. Kim, S.Y., B.; Chun, K.; Kang, W.; Choo, J.; Gong, M.
&Joo, S., "Catalytic effect of laser ablated Ni nanoparticles
in the oxidative addition reaction for a coupling reagent of
benzylchloride and bromoacetonitrile". J MolCatal A: Chem, 2005.
226: p. 231-234.
36. Link, S.B., C.; Nikoobakht, B. & El-Sayed, M.,
"Laser-induced shape changes of colloidal gold nanorods using
femtosecond and nanosecond laser pulses". J Phys Chem B, 2000. 104:
p. 6152-6163.
37. Kawasaki, M.N., N., "1064-nm laser fragmentation of thin Au
and Ag flakes in acetone for highly productive pathway to stable
metal nanoparticles". Appl Surf Sci, 2006. 253: p. 2208-2216.
38. Tarasenko, N.B., A.; Nevar, E. &Savastenko, N.,
"Synthesis of nanosized particles during laser ablation of gold in
water". Appl Surf Sci 2006. 252: p. 4439-4444.
39. Tsuji, T.I., K.; Watanabe, N. & Tsuji, M., "Preparation
of silver nanoparticles by laser ablation in solution: influence of
laser wavelength on particle size". Appl Surf Sci, 2002. 202: p.
80-85.
40. Tsuji, T.K., T. & Tsuji, M., "Preparation of nano-Size
particle of silver with femtosecond laser ablation in water".
Applied Surface Science, 2003. 206: p. 314-320.
41. Wiley, B.S., Y.; Mayers, B. & Xi, Y., "Shape-controlled
synthesis of metal nanostructures: the case of silver.". ChemEur,
2005. 11: p. 454-463.
42. Merga, G.W., R.; Lynn, G.; Milosavljevic, B. &Meisel,
D., "Redox catalysis on “naked” silver nanoparticles". J PhysChem C
2007. 111: p. 12220-12226.
43. Evanoff, J.C., G., "Size-controlled synthesis of
nanoparticles. 2. measurement of extinction, scattering, and
absorption cross sections". J PhysChem B, 2004. 108: p.
13957-13962.
44. Oliveira, M.U., D.; Zanchet, D. &Zarbin, A., "Influence
of synthetic parameters on the size, structure, and stability of
dodecanethiol-stabilized silver nanoparticles". J Colloid Interface
Sci, 2005. 292: p. 429-435.
45. Shchukin, D.G.R., I.L. &Sukhorukov, G., "Photoinduced
reduction of silver inside microscale polyelectrolyte capsules".
ChemPhysChem, 2003. 4: p. 1101-1103.
46. Jin, R.C., Y.C.; Hao, E.; Metraux, G.S.; Schatz, G.C.
&Mirkin, C., "Controlling anisotropic nanoparticle growth
through plasmon excitation". Nature, 2003. 425: p. 487-490.
47. Yin, Y.L., Z-Y.; Zhong, Z.; Gates, B. &Venkateswaran,
S., "Synthesis and characterization of stable aqueous dispersions
of silver nanoparticles through the Tollens process". J Mater Chem,
2002. 12: p. 522-527.
48. Ahmad, A.M., P.; Senapati, S.; Mandal, D.; Khan, M.I.;
Kumar, R. &Sastry, M., "Extracellular biosynthesis of silver
nanoparticles using the fungus Fusarium oxysporum". Colloids and
Surfaces B: Biointerfaces, 2003. 28: p. 313-318.
49. Ankamwar, B.D., C.; Ahmad, A. &Sastry, M., "Biosynthesis
of gold and silver nanoparticles using Emblicaofficinalis fruit
extract, their phase transfer and transmetallation in an organic
solution". J Nanosci Nanotechnol, 2005. 5: p. 1665-1671.
50. Korbekandi, H.I., S. &Abbasi, S., "Production of
nanoparticles using organisms". Critical Reviews in Biotechnology,
2009. 29: p. 279-306.
51. Iravani, S., "Green synthesis of metal nanoparticles using
plants". Green Chem, 2011. 13: p. 2638-2650.
52. Haefeli, C., Franklin, C, Hardy, K, "Plasmid-determined
silver resistance in Pseudomonas stutzeri isolated from a silver
mine.". J. Bacteriol., 1984. 158: p. 389-392.
FTIR-Nano Powder-
NameDescription
4000 400350030002500200015001000500
100
0
10
20
30
40
50
60
70
80
90
cm-1
%T
1384.63cm-1
3417.14cm-1
1628.33cm-1 1101.48cm-1
1030.46cm-1
2926.16cm-1
1193.85cm-1 618.71cm-1
2855.21cm-1
824.29cm-1
2395.93cm-1
2426.26cm-1
910.30cm-12092.04cm-1