Photonic crystals in biology

Poster Session, Tuesday, June 15
Theme A1 - B702
Preparation and characterization of silver nanoparticles by an eco-friendly approach
Reda El-Sh ishtawy 1 * Abdullah Asiri 1 and Maha Al-Otaibi 1
Department of Chemistry, Faculty of Science, King Abdul-Aziz University, Jeddah 21589, PO Box 80203, Saudi Arabia
1
Abstract-This work reports on an environmentally benign method for the preparation of AgNPs in aqueous solution using glucose as the
reducing agent in water/ micelles system, in which cetyltrimethylammonium bromide (CTAB) was used as capping agent (stabilizer).
Spectrophotometric method was used to monitor the formation of AgNPs under different conditions such as a) concentration of sodium
hydroxide, b) concentration of glucose, c) concentration of silver nitrate d) concentration of CTAB, and e) reaction time were used so as to find
out the optimum conditions for the preparation of AgNPs.
Silver nanoparticles (AgNPs) have received much more
attention in recent years due to their unique physical, optical,
electrical, magnetic, and chemical properties and their
potential application in molecular electronic field [1].
Therefore, extensive research has gone into developing
suitable preparation techniques to form AgNPs. These include
chemical reduction, microorganisms induced reduction as well
as photochemical and high energy radiation induced reduction
of silver salt solution. Among these methods, chemical
reduction is the most extensively investigated method [2-6].
Figure 1 shows the UV-vis absorption spectrum of a diluted
solution of AgNPs in which we can see a narrow absorption at
403 nm (plasmon band) indicating the presence AgNPs. The
size of the AgNPs were determined with the help of
transmission electron microscope (Fig. 2). Also, a comparative
kinetic formation of AgNPs using ultrasonic and conventional
heating conditions were made and the result obtained indicates
(Figure 3) that the rate of formation of AgNPs using ultrasonic
condition was about 1.5 times better than that obtained using
conventional heating. The result indicates the necessity of
using CTAB as capping and stabilizing agent for AgNPs.
nanoparticles. A future work is being under investigation to
explore the viability of using AgNPs in different biomedical
and photonic applications.
Figure 2. TEM image of the as-prepared silver nanoparticles.
ln(At-Af)
1
0
-1 0 2 4 6 8 10 12 14
-2
-3
-4
-5
-6
-7
-8
yUS = -0.5891x + 0.2431
R2 = 0.9943
yCH = -0.3864x - 0.0064
R2 = 0.9693
Time (min)
25 Times diluted sample Concentrated sample
Figure 3. Plots of ln(A t -A f ) versus time of AgNPs formation under
ultrasonic and conventional conditions. Prepartion condition:[Ag
NO 3 ] = 2.5 mM; [glucose] = 2.5 mM; [CTAB] = 0.5 mM; [NaOH] =
25 mM at 50 o C.
*Corresponding author: elshishtawy@hotmail.com
Figure 1. UV–vis spectrum of the as-prepared silver nanoparticles (25
times diluted sample). Prepartion condition: [Ag NO 3 ] = 2.5 mM;
[glucose] = 2.5 mM; [CTAB] = 0.5 mM; [NaOH] = 25 mM and
reaction time was 20 min at 50 o C.
In conclusion, uniform AgNPs have been successfully
prepared in glucose/CTAB micelles. CTAB displays excellent
properties in the preparation and stabilization of silver
[1] N.G.Khlebtsov, L. A. Dykman, J. Quant. Spectrosc. Radiat.
Transfer, 111, 1–35 (2010) and references cited therein.
[2] R. Janardhanan, M. Karuppaiah, N. Hebalkar, T. N. Rao,
Polyhedron, 28, 2522–2530 (2009) and references cited therein.
[3] K.K. Ghosh, S. Kolay, J. Dispersion Sci. Technol., 29, 676–681
(2008).
[4] V. K. Sharma, R. A. Yngard, Y. Lin, Adv. Colloid Interface Sci.,
145, 83–96 (2009) and references cited therein.
[5] Y. Yin, Z-Y. Li, Z. Zhong, B. Gates, Y. Xia,S. Venkateswaran, J.
Mater. Chem., 12, 522–527 (2002).
[6] N. R. Jana, L. Gearheart,C. J. Murphy, Chem. Commun., 2001,
617–618.
6th Nanoscience and Nanotechnology Conference, zmir, 2010 214