Transcript Silver Nanoparticles-Loaded Calcium Alginate Beads

SILVER NANOPARTICLES-LOADED
CALCIUM ALGINATE BEADS EMBEDDED
IN GELATIN SCAFFOLDS AND THEIR
RELEASE CHARACTERISTICS
Mae Fah Luang University
Presented by:
Porntipa Pankongadisak
Materials Science, School of Science
Mae Fah Luang University
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SILVER NANOPARTICLES (AgNPs)
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SILVER NANOPARTICLES (AgNPs)
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ELECTROHYDRODYNAMIC
SPRAYING (EHDA)
Negative electrode
Ground electrode
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ALGINATE
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SCAFFOLDS
Scaffolds
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GELATIN
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PROBLEMS
SOLVE THE PROBLEMS
“Embedding them in a polymer matrix
may reduce their cytotoxic effect”
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OBJECTIVES
1)
To prepare the AgNPs-loaded calcium alginate beads embedded in
gelatin scaffolds
2)
To characterize the AgNPs-loaded calcium alginate beads embedded
in gelatin scaffolds (morphology, thermal properties, mechanical
properties, water swelling and weight loss behavior and, release
characteristic of Ag+ ions)
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Part 1: Preparation of pure calcium alginate beads and
AgNPs-loaded calcium alginate beads
4%w/w AgNO3 solution
was initially prepared and
mixed with 1.5% w/v of
Na alginate.
Negative electrode
AgNO3/alginate solution
was irradiated by UV light
for 1 h.
Ground electrode
Alginate beads incorporated
with AgNPs were fabricated
by EHDA.
The wet and dry beads were observed the
morphology and size by Optical Microscope
(OM) and Scanning Electron Microscope
(SEM), respectively.
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Part 2: Preparation of AgNPs-loaded calcium alginate beads
embedded in gelatin scaffolds
5%w/v gelatin solution
was initially prepared
and added genipin as
crosslinking agent.
The solution was mixed to
obtain homogeneous solution by
magnetic stirrer for 1 h.
The dry beads were added into
the
GP-crosslinked
gelatin
solution and then poured it into
the mold to form gel.
The frozen gel was lyophilized by
freeze-dryer for over night to obtain
the porous scaffolds.
The gel was left in the room temp.
for crosslinking over night and
then it was freezed at -40 °C.
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Part 3: Characterization of AgNPs-loaded calcium
alginate beads embedded in gelatin scaffolds
Morphology
Scanning Electron Microscope (SEM)
Thermal properties
Thermogravimetric Analyzer (TGA)
Mechanical properties
Universal Testing Machine (UTM)
Water swelling and
Weight loss properties
Release characteristic
Waterswelling (%) 
M - Md
Md
M -M
i
d
 100
 100, Weightloss (%) 
M
i
Total Immersion Method in PBS at 37 °C
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Morphology
Table 1: Optical micrographs (OM), scanning electron micrographs (SEM) and
diameters of the pure calcium-alginate beads and AgNPs-loaded calciumalginate beads
Observed by
Sample
OM
Diameter (µm)
SEM
Diameter(µm)
Control
523.68 ± 17.36
149.46 ± 12.26
AgNPs
475.97 ± 16.09
143.65 ± 13.35
Adding Ag into the beads affected the size of beads to decrease.
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Morphology
Table 2: Selected SEM image of the pure calcium alginate beads embedded in gelatin
scaffolds and AgNPs-loaded calcium alginate beads embedded in gelatin scaffolds
Sample
SEM
Pore size (µm)
Pure beads embedded in
gelatin scaffolds
242.90 ± 65.72
AgNPs-loaded beads
embedded in gelatin
scaffolds
261.41 ± 85.71
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Thermal properties
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Pure beads embedded in scaffolds
AgNPs-loaded beads embedded in scaffolds
Weight loss (%)
100
80
60
40
20
0
100
200
300
400
o
Temperature ( C)
500
600
Figure 2: Thermogravimetric analysis (TGA) of the pure calcium alginate beads
embedded in gelatin scaffolds and AgNPs-loaded calcium alginate beads embedded in
gelatin scaffolds
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Mechanical stability
Table 3: Compressive modulus of the pure calcium alginate beads embedded in
gelatin scaffolds and AgNPs-loaded calcium alginate beads embedded in gelatin
scaffolds
Sample
Compressive Modulus (kPa)
Pure beads embedded in gelatin
scaffolds
3.60 ± 0.85
AgNPs-loaded beads embedded in
gelatin scaffolds
2.78 ± 1.03
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Water swelling
Pure beads embedded in scaffolds
AgNPs-loaded beads embedded in scaffolds
Water swelling (%)
1500
1000
500
0
1
5
3
Submersion time (Day)
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Figure 3: Water swelling of the pure calcium alginate beads embedded in gelatin
scaffolds and AgNPs-loaded calcium alginate beads embedded in gelatin scaffolds.
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Weight loss
40
Pure beads embedded in scaffolds
AgNPs-loaded beads embedded in scaffolds
Weight loss (%)
30
20
10
0
1
3
5
Submersion time (Day)
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Figure 4: Weight loss of the pure calcium alginate beads embedded in gelatin scaffolds and
silver nanoparticles-loaded calcium alginate beads embedded in gelatin scaffolds.
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Release characteristic
Cumulative release of silver ions
(%, based on actual amount of silver
100
80
60
40
20
0
0
1
2
3
4
5
6
7
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Submersion time (Day)
Figure 5: Cumulative release profiles of Ag+ ions from AgNPs-loaded calcium alginate
beads embedded in gelatin scaffolds in phosphate buffer solution at 37 °C.
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CONCLUSIONS
The AgNPs-loaded calcium alginate beads embedded
in gelatin scaffolds were successfully fabricated.
The incorporation of AgNPs-loaded into the calcium
alginate beads decreased the size of beads.
The morphology of the AgNPs-loaded calcium
alginate beads embedded in gelatin scaffolds showed
the interconnected pore structure .
The incorporation of AgNPs into the calcium
alginate beads embedded in gelatin scaffolds
decreased the strength of materials.
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CONCLUSIONS
The water swelling and weight loss behavior
of the scaffolds increased with an increase in
the submersion time.
The release of Ag ions from the scaffolds
gradually increased with increase in
submersion time and then reached a plateau
value at day 3, and continually increased to
reach 80% release at day 7.
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REFERENCES
1) Lee YM, Kim SS, Park MH, Song KW, Sung YK, Kang K (2000) J
Mater Sci 11:817-823
2) del Valle LJ, Roa M, Díaz A, Casas MT, Puiggalí J, Rodríguez-Galán A
(2012) J Polym Res 19:9792
3) Sharma VK, Yngard RA, Lin Y (2009) Adv Colloid Interface Sci
145:83-96
4) Yoksan R, Chirachachai S (2009) Mater Chem Phys 115:296–302
5) Ogończyk D, Siek M, Garstecki P (2011) Biomicrofluidics 5:013405
6) Knight CG (1982) J Membr Sci 12:131–132
7) Ding L, Lee T, Wang C (2005) J Control Release 102:395–413
8) Xie J, Lim LK, Phua Y, Hua J, Wang C (2006) J Colloid Interf Sci
302:103–112
9) Ciach T (2006) Int J Pharm 324:51–55
10)Cloupeau M (1994) J Aerosol Sci 25:1143-1157
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ACKNOWLEDGEMENTS
“The authors would like to acknowledge the financial support from the Research,
Development and Engineering (RD&E) fund through The National Nanotechnology
Center (NANOTEC), The National Science and Technology Development Agency
(NSTDA), Thailand (P-11-00986) to Mae Fah Luang University (MFU) and Thailand
Graduate Institute of Science and Technology (TGIST) (TG-55-99-55-048M)”
Thank You For Your Attention