Review of Literatures on Noble Metal Nanoparticles: Properties …shodhganga.inflibnet.ac.in/bitstream/10603/39151/7/07_chapter 2.pdf · Noble Metal Nanoparticles: Properties and

Review of Literatures on

Noble Metal Nanoparticles:

Properties and Applications

Chapter 2

“Prepare for the unknown by studying how others in the past have coped with

the unforeseeable and the unpredictable.”

-George S. Patton

Chapter 2 Review of Literatures

Center for Interdisciplinary Research, D. Y. Patil University, Kolhapur 26

“Nanotechnology in medicine is going to have a major impact on the survival of the human race.” -Bernard Marcus

2.1. Introduction

The Unique optical property of the noble metal nanoparticles has made

them a potential candidate in the nanotechnology field. Zijlstra et al. have

demonstrated a DVD disk having storage capacity of 10 terabytes,

approximately 2000 movies of convectional size [1]. This is possible because

of the superior optical properties of randomly oriented gold nanorods

embedded in the disk. As the metal nanoparticles show size and shape

dependant optical properties, Zijlstra and coworkers used optical spectrum and

different polarization directions to store data. The enhancement in the optical

and photothermal properties of noble metal nanoparticles e.g., AgNPs, gold

nanoparticles, Pb nanoparticles etc., arises from resonant oscillation of their

free electrons in the presence of light, also known as localized surface plasmon

resonance (LSPR). The plasmon resonance can either radiate light (Mie

scattering), a process that finds great utility in optical and imaging fields, or be

rapidly converted to heat (absorption); the latter mechanism of dissipation has

opened up applications in several new areas.

So here, this chapter is divided into following parts. Some historical

evidences of use of AgNPs along with other noble metal nanoparticles are

given at first. The overview of various properties of AgNPs is described

further. Finally, we highlight some recent applications based on properties of

AgNPs.

2.2. Historical Perspective

In ancient time, silver was considered more precious than gold and

symbol of purity. Hippocrates proclaimed that silver contained medicinal

properties and could cure multiple maladies 10. Since silver was publicized to

have antiseptic properties, Phoenicians used silver vials for food storage to help

prevent spoilage. Ravelin (1869) and von Nageli (1893) had done pioneering

work in the study of anti-bacterial properties of silver [2]. Based on silver a



number of products commercialized throughout the 20th

century like Katadyn,

Movidyn, Argyrol, Alagon, Tetrasil, etc. [3]. Prior to the wide spread use of

antibiotics, during World War I silver compounds were used to help prevent

infection.

History tells about the use of these noble metals in stained glass to

produce the beautiful colors of drink cups, such as the Lycurgus cup [4], or

ancient windows, for example, in the Altenberg dome near Cologne in

Germany [5]. The early alchemist tried to produce portable gold, ‘‘the elixir of

life’’ as they considered gold as indestructible and have enormous medicinal

importance [6]. The German bacteriologist Robert Koch discovered in 1890

that low concentrations of potassium gold cyanide, K[Au(CN)2] had

antimicrobial activity against the tubercle bacillus. From thereafter gold is

introduced in modern medicine [7]. During the Vedic period (1000BC-600BC)

in ancient India, the use of gold, in the form of swarna bhasma (meaning, gold

ash), is suggested for medicinal purposes started [8].

In1856, Faraday had hypothesized that the color of ruby glass and its

aqueous solutions of gold (mixed with either SO3 or phosphorus), is due to

finely divided gold particles [9]. Stoke had different opinion about the

existence of a purple gold oxide, apparently prompted Faraday’s famous

electrical discharge method for preparing aqueous gold colloids [10]. It is

noteworthy that Faraday did not have a quantitative theoretical framework, but

seems to have based his postulate on an intuitive understanding of highly

reflective metals and scattering processes.

Gustav Mie’s 1908 paper represents the first rigorous theoretical

treatment of the optical properties of spherical metal particles [11, 12]. Mie’s

theory yielded extinction coefficients for nanoscopic gold particles which

compared well with the experimental spectra of gold sols and unlike Maxwell-

Garnett theory, was applicable to spheres of any size. Mie scattering theory is

applied today to a variety of systems, including nonmetal particles. His basic

approach has also been adapted to other shapes, such as cylinders [13] and

ellipsoids [14].



In 1727, a German professor, John Herman Schulze first revealed that

on exposure to light silver salts turned into black. Silver salts then after were

further explored and were for many years the critical component of

photographic plate. Platinum was discovered on the alluvial sands of the Pinto

River in Columbia and confirmed as new metal by Italian-French scientist

Julius Caesar Scaliger who concluded that the metal was not silver and in fact a

new element [15]. In 1845, Michel Peyrone synthesized cisplatin (platinum-

containing anti-cancer drugs) [16] and Alfred Werner, in 1893, elucidated the

structure of cisplatin whereas Rosenberg studied the antitumor activity of

cisplatin. After successful studies and trials, in 1978 the US by the Food and

Drug Administration approved the use of cisplatin as anticancer drug.

2.3. Properties of Noble Metal Nanoparticles

2.3.1. Optical Properties

Metal nanoparticles exhibit unique shape and size-dependent optical

properties. In particular, the extinction spectra of noble metal nanoparticles are

dominated by localized surface plasmon resonance (LSPR). These resonances

are attributed to a coherent excitation of the conduction band electrons, excited

by means of an electromagnetic field. In the presence of the oscillating

electromagnetic field of the light, the free electrons of the metal nanoparticle

undergo a collective coherent oscillation with respect to the positive metallic

lattice. The general case of an interaction between an electromagnetic field and

a spherical metal nanoparticle is schematically depicted in figure 2.1. The field

in the nanoparticle is in homogeneous and its optical response is rather

complex [17].



Figure 2.1 Schematic of plasmon oscillation for a sphere, showing the

displacement of the conduction electron charge cloud relative to

the nuclei [15]

Large number of atoms present on the surface of nanoparticles

contributes electron cloud on the surface of nanoparticles. As shown in the

figure 2.1, the movement of these free electrons under the influence of the

electric field vector of the incoming light leads to a dipole excitation across the

particle. This induces positive polarization charge on cationic lattice. This

charge acts as a restoring force, and brings back electron cloud to its original

position, thus causing the oscillations of the electron cloud. In this manner a

dipolar oscillation of electrons is created (called plasma oscillation) with a

certain frequency called plasmon frequency. The surface plasmon resonance is

a collective excitation mode of the plasma localized near the surface. However,

the resonance frequency of the surface plasmon is different from an ordinary

plasma frequency. If the frequency of the excitation light field is in resonance

with the frequency of this collective oscillation, even a small exciting field

leads to a strong oscillation [18, 19].

The rigorous calculations made by Mie are traditionally referred to as

the Mie theory. The theory of light scattering by small spheres was already



developed, but it was Mie who applied it to the scattering and absorption of

metal spheres. Mie theory describes characteristic light absorption of spherical

metal nanoparticles which demonstrates that the absorption does not strongly

depend on the particle size in the size range of 3 to 10 nm. The particles start

showing size dependence of the plasmon resonance band below the size limit

of 10 nm and ultimately disappear for particles of size less than 2 nm. This is

attributed to the decreasing validity of the free electron gas model assumption

[20, 21].

The electric field intensity and the scattering and absorption cross-

sections are all strongly enhanced at the LSPR frequency [22] which for gold,

silver, and copper lies in the visible region [22, 23]. Since copper is easily

oxidized, gold and silver nanostructures are most attractive for optical

applications. The ability to integrate metal nanoparticles into biological

systems has had greatest impact in biology and biomedicine. Due to the

plasmonic properties of gold and silver nanostructures, they are being utilized

for biodiagnostics, biophysical studies, and medical therapy.

2.3.2. Catalytic properties

Metal nanoparticles like silver, palladium and gold have attracted a great

interest in scientific research and industrial applications, due to their unique

large surface-to-volume ratios. Catalytic activity of usually work on the surface

of metals, the metal nanoparticles have been considered as promising materials

for catalysis, which have much larger surface area per unit volume or weight of

metal than the bulk metal. The size of the nanoparticle is one of the most

important factors in the catalytic activity. As surface-to-volume ration increases

the catalytic activity of the metal nanoparticles increases which ultimately

increases with decrease in the size of the nanoparticles. Pd and Ag

nanoparticles can be used for the hydrogenation of oxygen-containing olefins

and epoxidation of ethylene with oxygen, respectively [24]. Thus, metal

nanoparticles have been demonstrated for homogeneous and heterogeneous

catalytic activity. The catalytic activity is also shape dependent phenomenon as



the shape of the nanoparticle changes the surface-to-volume ration also changes

which causes the exchange of electrons. The hydration of acrylonitrile was

catalyzed by Cu-Pd bimetallic nanoparticles [25] and like that plenty of

bimetallic have been studied for the catalytic activity.

2.3.3. Electronic properties

Metal nanoparticles show different electronic properties below certain

size limit. There will be change in electronic distribution in metal which may

transform some metal into semiconductor at nanometer scale. For example,

gold nanoparticles act as quantum dot below certain size range [26]. Coulomb

blockade is important and interesting effect that occurs when nanoparticles

embedded between metal-insulator-metal junctions show charging of

differential capacitance or charging at low temperature even at zero bias. This

effect is a result of extremely small capacitance of the metal nanoparticles [27].

2.3.4. Melting point

Many physical properties of materials, especially the melting point,

change as the physical size of the material approaches from the micro to

nanoscale [28]. Changes in melting point occur due to a much larger surface-

to-volume ratio of nanoscale material than bulk materials, altering

thermodynamic and thermal properties. The melting temperature also decreases

as the metal particle size decreases. The melting point is also marginally

depending on shape of the metal nanoparticles. The melting point decrease with

the large surface-to-volume ratio. The surface areas of nanoparticles in

different shape will be different even in the identical volume, and the area

difference is large especially in small particle size.



2.4. Applications of Noble Metal Nanoparticles

Figure 2.2. The schematic of the various applications of noble metal

nanoparticles in the therapeutics, imaging, diagnosis

Metal nanoparticles due to the varies physical, chemical and biological

properties also size and shape dependent phenomenon have potential

application in vast area like antimicrobial agents, therapeutic, imaging,

diagnostic, catalysis, environmental decontamination etc., (figure 2.2). The

following section will briefly cover the various metal nanoparticles used in

various applications.

2.4.1. Antimicrobial properties

Among noble metal nanoparticles, silver, copper and gold have been

studied extensively for antimicrobial activity against pathogenic

microorganisms [29]. High surface areas to volume ratios with unique

physicochemical properties of noble metal nanoparticles are contributing

effective antimicrobial activities [30]. Lots of burden on the economy for the

developing countries is rising due to the production cost of traditional

antibiotics [31]. Also, microorganisms are developing resistance against these

antibiotics. So continues development in the traditional antibiotic is required

desperately. The biological synthesis method of metal and metal oxide



nanoparticles have been explored since few years. So the production cost of

these materials is too less than chemical antibiotics. It is also demonstrated that

the rate of acquiring resistance to the nanoparticles is slower as compared to

conventional antibiotics [32]. Antimicrobial mechanisms of nanomaterials

include: 1) photocatalytic production of reactive oxygen species (ROS) that

damage cellular and viral components, 2) damaging the bacterial cell

wall/membrane, 3) disruption of energy transduction, and 4) inhibition of

enzyme activity and DNA synthesis [30, 33-35]. Figure 2.3 shows the brief

mechanisms of antimicrobial activity of metal nanoparticles.

Figure 2.3. Schematics of antimicrobial mechanisms of AgNPs [39]

The antibacterial property of silver has been used since antiquity. Silver

in the forms of metallic silver, silver sulfadiazine, and silver nitrate has been

used for burn wound treatment and disinfection of catheters, dental

instruments, and bacterial infection control [36]. Using after discovery of

antibiotics in the 1940s silver become out of favor to treat bacterial infections

[37]. The clinical use of silver is now under extensive research as antibiotics-

resistant bacteria are emerging and showing less or no response to conventional

antibiotics [38]. AgNPs among other metallic NPs have proven to be the most



lethal against viruses, bacteria, and other eukaryotic microorganisms [39]. The

respiratory chain and cell division are affected by AgNPs which finally lead to

cell death [40]. The antimicrobial activity of AgNPs is oppositely allied to size

and shape [41]. Amalgamation of AgNPs with antibiotics such as penicillin G,

erythromycin, amoxicillin, and vancomycin, resulted in improved and

synergistic antimicrobial effects against Gram-positive and Gram-negative

bacteria [42, 43]. AgNPs have been used in fabrics, textiles, surgical masks and

medical devices, gels and lotions [44]. Irreversible pigmentation in the skin

(argyria) and eyes (argyrosis) with also other toxic effects like irritations, organ

damage, and blood count change are the possible adverse effects due to

prolonged exposure of Ag+ ions [45]. On the other hand, metallic silver appears

to have a minimal risk to health and AgNPs are recommended to be non-toxic

in some studies [46], but concentration-dependent adverse effects of AgNPs on

the mitochondrial activity are also report. So AgNPs to be used as the sole

antimicrobial agent against diseases is required to undergo thorough study of

effects to mammalian and other animal cells.

Near-infrared (NIR) light-absorbing AuNPs, nanoshells, nanorods, and

nanocages have been demonstrated to kill bacterial growth via irradiation with

focused laser pulses of suitable wavelengths [47]. AuNPs have strong attraction

towards negatively charged cell membrane of microorganisms which is the

main cause of the antimicrobial activity of the AuNPs [48], which was also

supported by the observation that cationic particles were found to be slightly

toxic while anionic particles were not. AuNPs conjugated with antimicrobial

agents and antibodies have been investigated to obtain selective antimicrobial

effects. For example, Au NPs conjugated with anti-proteinA antibodies for the

selective killing of S. aureus, which target the bacterial cell surface, was

reported [49]. Laser induced hyperthermia caused formation of the bubble

which is used for the selective killing of the bacteria [50]. Effective inhibition

of antibiotic resistant microorganisms with the conjugation of antibiotic is

demonstrated [51]. Therefore, AuNPs can be promising adjuvants for antibiotic



therapy in treating serious bacterial infections with minimal adverse effects as

AuNPs have been demonstrated to be less toxic to mammalian cells.

2.4.2. In therapeutics

Versatile noble metal nanoparticles are agents with a variety of

biomedical applications and sensitive diagnostic assays [50], radiotherapy

enhancement, and thermal ablation [51, 52], as well as gene delivery and drug

[53, 54]. In addition, noble metals NPs have been projected as non toxic

carriers for drug and gene-delivery applications [55]. Theranostic application is

the major advantage of noble metal nanoparticles where they are being

explored to use as simultaneous diagnostic as well as therapeutics purpose.

It is necessary to use designed and engineered NPs especially in therapy

that can be targeted to tissues of interest, also can produce specific, desired

effects. The function of AgNPs as antibacterial agents has been well

established. Anti-viral properties of biologically formed AgNPs are more

effective than chemically synthesized AgNPs [56]. Vero cells co-incubated

with AgNPs were reported to prevent plaque formation after being infected

with the Monkey pox virus [57] Metallic nanoparticles have also been

described as a possible HIV preventative therapeutic [58]. Metallic

nanoparticles have also been effective antiviral agents against herpes simplex

virus, influenza, and respiratory syncytial viruses [59]. The potential

therapeutic application of noble metal nanoparticles represents an attractive

platform for cancer therapy in a wide variety of targets and clinical settings. It

is shown that ‘‘naked’’ gold nanoparticles inhibited the activity of heparin-

binding proteins, such as VEGF1and bFGF in vitro and VEGF induced

angiogenesis in vivo [60]. Dalton’s lymphoma ascites (DLA) cell lines co-

incubated with AgNPs displayed a dose dependent toxicity through activation

of caspase-3 and inhibition of cellular proliferation. Furthermore, tumor

bearing mice injected with AgNPs demonstrated a reduction of ascites

production (65%) and tumor progression compared to the sham treated mice

[61] which have been shown to have applications in cancer treatment. Human



colon carcinoma cells (HT29) showed a dose and time dependent response

when exposed to platinum nanoparticles (Pt-NP) [62].

Gold nanoparticles have shown potential as intracellular delivery

vehicles for antisense oligonucleotides [63] and for therapeutic siRNA by

providing protection against RNAses and ease of functionalization for selective

targeting [64] have emerged as a powerful and useful tools to block gene

function and for sequence-specific posttranscriptional gene silencing, playing

an important role in down regulation of specific gene expression in cancer

cells. Metallic nanoparticles may offer an advantage in radiotherapy area by

utilizing their excellent optical properties, surface resonance, and wavelength

tunability. For example X-ray irradiation, gold nanoparticles can induce

cellular apoptosis through the generation of radicals which can be used as

therapy without harming the surrounding healthy cells [65]. The surface size of

AgNPs enhances the thermal sensitivity of glioma cells. Pioneering work by

Pitsillides illustrated that the surface plasmon resonance (SPR) of nanoparticles

is easily exploited for photo-dynamic therapy (PDT) anti-cancer therapy [66].

El-Sayed group demonstrated that AuNPs are effective PDT agents and could

‘‘seek and destroy’’ cancerous cells [67].

The metallic nanoparticles have been demonstrated promising as PDT

and hyperthermic agents for the treatment of cancer. Rapid heating of metallic

nanoparticles occurs on the application of magnetic field. The gold particles by

the oscillating magnetic field produce electric currents [68]. The heat

generation occurs due to eddy which dissipates into the surrounding from

nanoparticles, causing thermal ablation [69]. Figure 2.4 is demonstrating the

treatment of cancer using metallic nanoparticles by inducing hyperthermia with

the aid of radiotherapy. The toxicity of metallic nanoparticles to the normal

tissue or cells is the major concern of the use of metallic nanoparticles for the

use of cancer hyperthermia.



Figure 2.4. Therapeutic application of noble metal nanoparticles by the

induction of hyperthermia with the assists of radiotherapy [64]

2.4.3. In diagnostics and imaging

Due to the strongly enhanced LSPR, noble metal nanoparticles scatter

light very strongly at the LSPR frequency, making them very promising for

optical imaging and labeling of biological systems [49]. While scattering and

absorption are competing processes, the relative contribution of scattering

increases rapidly with increase in the nanostructure volume. Dark-field

microscopy shows (right) HSC cancer cells clearly defined by the strong LSPR

scattering from (top) gold nanospheres and (bottom) gold nanorods bound

specifically to the cancer cell surface, whereas (left) HaCat healthy cells have

(top) gold nanospheres and (bottom) gold nanorods randomly dispersed

without specific binding (figure 2.5). The scattering color (LSPR frequency) of

the nanospheres and nanorods can be clearly distinguished. While the

scattering from a 10-nm gold nanoparticle is negligible, an 80-nm gold

nanoparticle offers scattering 5 orders of magnitude larger than the typical



emission from a dye. Such highly enhanced cross-sections offer sensitive and

highly contrasted imaging allowing use of the much simpler but powerful dark-

field microscopy [64].

Figure 2.5. Molecular-specific imaging of cancer using metal nanoparticle /

anti-EGFR conjugates [21]

The noble metal nanoparticles can be used for the simultaneous actuation and

tracking in vivo along with their therapeutic capabilities. Most noble metal

nanoparticles for in vivo imaging and therapy have been designed to strongly

absorb in the near infrared (NIR) so as to be used as effective contrast agents

whereas at NIR biological components minimum light absorption [46]. The use

of PEG-coated AuNPs for in vivo computed tomography CT contrast agent was

shown to increase image contrast, which allows to reduce the radiation dosage

needed, allow to overcome the limitations of conventional contrast agents (e.g.,

iodine-based compounds), such as short imaging times due to rapid renal

clearance, renal toxicity, and vascular permeation [46]. In photoacoustic



imaging (PAI) and photoacoustic tomography (PAT), Au-nanocages enhanced

the contrast between blood and the surrounding tissues by up to 81%, allowing

a more detailed image of vascular structures at greater depths [69].

2.4.4. In catalysis and environmental decontamination

Noble metals and bimetallic nanoparticles have shown their potential

use for the environmental application in conversion of hazardous chemical

compound to less toxic or non-toxic one. Liu et al. reported

hydrodechlorination of monochlorobenzene in the presence of colloidal

platinum nanoparticles stabilized on polyvinylpyrrolidone (PVP) [70].

Silver/gold (Ag/Au) bimetallic nanoparticles have also been reported as being

effective for dehalogenation processes. Using an underpotential deposition-

redox placement technique, Zhou used Ag/Au bimetallic nanoparticles as the

cathode in the electrochemical reduction of benzyl chloride [70].

Platinum/palladium (Pt/Pd) bimetallic nanoparticles, iron/silver (Fe-Ag) and

gold/platinum (Au-Pt) are increasingly being investigated for dehalogenation

and it is expected that with optimization of reaction conditions [70].

A number of contaminants such as lead and pesticides are affecting

water supplies globally due to their widespread use; pollutants of geochemical

origin such as arsenic and fluoride are currently found in selected countries. It

is quite evident that pesticides contain highly toxic recalcitrant groups and

hence are extremely difficult to break through normal synthetic routes of

degradation. A useful example of size-dependent catalysis has been

demonstrated through AgNPs-catalyzed reduction of nitrophenol to

aminophenol [66]. Contaminants such as pesticides are removed through

homogeneous or heterogeneous chemistry. A remarkable example is the

catalytic oxidation of CO with supported gold nanoparticles [71]. One of the

interesting application areas of noble metal nanoparticles in drinking water

purification is the sequestration of heavy metals. The first studies of the

interaction of metal ions with noble metal nanoparticles were in the early 1990s

[71]. Noble metal nanoparticles have extensively studied for the detection of



heavy metals and pesticides in the drinking water [72]. In addition, the biggest

class of contaminants affecting drinking water is microorganisms. Every year,

1.8 million people die from diarrheal diseases (including cholera); 90% are

children under five, mostly in developing countries. Worldwide, 1 billion

people lack access to safe drinking water, 2.4 billion to adequate sanitation.

Improved water supply reduces diarrhea morbidity by 6% to 25%; improved

sanitation reduces it by 32%. As discussed earlier, the antimicrobial activity of

the AgNPs has been top priority of the researcher which is now also being used

for the decontamination of water from pathogenic species [72].

2.5. Summary

The present chapter deals with some historical and theoretical

background of the noble metal nanoparticles. Due to their unique size and

shape dependent optical properties, metal nanoparticles have potential

applications in medicine and environmental field. This chapter gives some

glimpse of the properties, and applications of the noble metal nanoparticles in

various fields including health care and environmental decontamination.



References

1 P. Zijlstra, J.W.M. Chong, and M. Gu, Nature 459 (2009) 410.

2 As quoted in. A.B.G. Lansdown, in: U.-C. Hipler, P. Elsner (Eds.),

Biofunctional textiles and the Skin, vol. 33, Karger Publishers, 2006

3 G.A. Krause, US Patent No. 2046467, 7 Jul. 1936

4 The British Museum, The Art of Glass, The Lycurgus Cup,

http://www.britishmuseum.org/explore/onlinetours/museuman/exhibitio

n/theartofglass/thelycurguscup.aspx(accessed October 2009)

5 Gesamtansicht des Westfensters, http://www.altenberg-

dom.delbilder/53542596a00e70f3a/o000.html(accessed October 2009)

6 G. Kauffman, Gold Bull 18 (1985) 69.

7 R. Koch, On bacteriological research, August Hirsch Forest, Berlin,

1890.

8 C.L. Brown, G. Bushell, M.W. Whitehouse, D.S. Agrawal, S.G. Tupe,

K.M. Paknikar, and E.R.T. Tiekink, Gold Bull 40 (2007) 245.

9 L. P. Willimas, ed. The Selected Correspondence of Michael Faraday.

London: Cam-bridge University Press, 1971.

10 M. Faraday, Philos Trans 147 (1857) 145.

11 U. Kreibig, and M. Vollmer, Optical Properties of Small Metal Clusters.

Berlin: Springer, 1995.

12 G. Mie, Ann Phys 25 (1908) 377.

13 H. C. van de Hulst, Light Scattering by Small Particles. New York:

Dover, 1981.

14 S. Asano, and M. Sato, Appl Optics 19 (1980) 962.

15 I. Wood, Platinum, Benchmark Books, New York, 2004.

16 S. Trzaska, C&EN News 83 (2005) 3.

17 E. Dulkeith, T. Niedereichholz, T. A. Klar, J. Feldmann, G. von Plessen,

D. I. Gittins, K. S. Mayya, and F. Caruso, Phys Rev B 70 (2004)

205424.

18 P. K. Jain, X. Huang, I. H. El-Sayed, and M. A. El-Sayed, Acc Chem

Res 41 (2008) 1578.

19 S. A. Maier, Pasmonics, Fundamentals and Applications. New York:

Springer, 2007.

20 F. Hubenthal, Science 82 (2007) 378.

21 S. Park, M. Pelton, M. Liu, P. Guyot-Sionnest, and N. F. Scherer, J Phys

Chem C111 (2007) 116.



22 S. Eustis, and M. A. El-Sayed, Chem Soc Rev 35 (2006) 209.

23 U. Kreibig, and M. Vollmer, Optical Properties of Metal Clusters;

Springer: Berlin, 1995.

24 N. Toshima, Y. Shiraishi, and T. Teranishi, J Mol Catal A Chem177

(2001) 139.

25 Y. Wang, and N. Toshima, J Phys Chem B101 (1997) 5301.

26 G. Schon, and U. J. Simon, Colloid Polymer Sci, 273 (1995) 101.

27 R. P. Andres, T. Bein, M. dorogi, S. Feng, J. Jendorson, C. P. Kubiak,

W. Mahoney, R. G. Osifchin, and R. Reifenverger, Science 272 (1996)

1323.

28 T. Castro, R. Reifenberger, E. Choi, and R. P. Andres, Phys rev B

Condens matter 13 (1990) 8548.

29 H. H. Huang, X. P. Ni, G. L. Loy, C. H. Chew, K. L. Tan, F. C. Loh, J.

F. Deng, and G. Q. Xu, Langmuir 12 (1996) 909.

30 E. Weir, A. Lawlor, A. Whelan, and F. Regan, Analyst 133 (2008) 835.

31 H. C. Neu, Science 257 (1992) 1064.

32 M. Mühling, A. Bradford, J.W. Readman, P.J. Somerfield, and R.D.

Handy, Mar Environ Res 68 (2009) 278.

33 Q. Li, S. Mahendra, D.Y. Lyon, L. Brunet, M.V. Liga, D. Li, and P.J.

Alvarez, Water Res 42 (2008) 4591.

34 J.S. Kim, E. Kuk, K.N. Yu, J.H. Kim, S.J. Park, H.J. Lee, S.H. Kim,

Y.K. Park, Y.H. Park, C.Y. Hwang, Y.K. Kim, Y.S. Lee, D.H. Jeong,

and M.H. Cho, Nanomedicine 3 (2007) 95.

35 E.I. Rabea, M.E. Badawy, C.V. Stevens, G. Smagghe, W. Steurbaut,

Biomacromole 4 (2003) 1457.

36 D.L. Becker, S.C. Wilson, in: P.N. Cheremisinoff, F. Ellebush (Eds.),

Carbon Adsorption Handbook, Ann Harbor Science Publishers,

Michigan, 1980.

37 J.A. Bumpus, M. Tien, D. Wright, and S.D. Aust, Science 228 (1985)

1434.

38 M. Kumar, M. Grzelakowski, J. Zilles, M. Clark, and W. Meier, PNAS

104 (2007) 20719.

39 V.K. Sharma, R.A. Yngard, and Y. Liu, Adv Colloid Interface Sci 145

(2008) 83.

40 H.J. Klasen, Burns 26 (2000) 117.

41 S. Pal, Y.K. Tak, and J.M. Song, Appl Environ Microbiol 27 (2007)

1712.

42 A.R. Shahverdi, A. Fakhimi, H.R. Shahverdi, and S. Minaian,



Nanomedicine 3 (2007) 168.

43 A.M. Fayaz, K. Balaji, M. Girilal, R. Yadav, M. Tech, P.T.

Kalaichelvan, and R. Venketesan, Nanomedicine 6 (2010) 103.

44 M. Rai, A. Yadav, and A. Gade, Biotechnl Adv 27 (2009) 76.

45 N.R. Panyala, E.M. Peña-Méndez, J. Havel, J Appl Biomed 6(2008)

117.

46 G. Oberdörster, E. Oberdörster, and J. Oberdörster, Environ Health

Perspect 113 (2005) 823.

47 B.S. Sekhon, and S.R. Kamboj, Nanomedicine 6 (2010) 612.

48 H.J. Johnston, G. Hutchison, F.M. Christensen, S. Peters, S. Hankin, and

V. Stone, Crit Rev Toxicol 40 (2010) 328.

49 V. P. Zharov, K. E. Mercer, E. N. Galitovskaya, and M. S. Smeltzer,

Biophys J 15 (2006) 619.

50 X. Huang, I. H. El-Sayed, W. Qian, and M. A. El-Sayed, J Am Chem

Soc 128 (2006) 2115.

51 D. P. O’Neal, L. R. Hirsch, N. J. Halas, J. D. Payne, and J. L. West,

Cancer Lett 209 (2004) 171.

52 P. K. Jain, I. H. El-Sayed, and M. A.El-Sayed, Nano Today 2 (2007) 18.

53 P. K. Jain, K. S. Lee, I. H. El-Sayed, and M. A. El-Sayed, J Phys Chem

B 110 (2006) 7238.

54 K. L. Kelly, E. Coronado, L. L. Zhao, and G. C. Schatz, J Phys Chem B

107 (2003) 668.

55 P. K. Jain, X. Huang, I. H. El-Sayed, and M. A. El-Sayed, M.

Plasmonics 2 (2007) 107.

56 B. De Gusseme, L. Sintubin, L. Baert, E. Thibo, T. Hennebel, G.

Vermeulen, M. Uyttendaele, W. Verstraete, and N. Boon, Appl Environ

Microbiol 76 (2009) 1082.

57 J. Rogers, C. Parkinson, Y. Choi, J. Speshock, and S. Hussain,

Nanoscale Res Lett 3 (2008) 129.

58 M.-C. Bowman, T. E. Ballard, C. J. Ackerson, D. L. Feldheim, D. M.

Margolis, and C. Melander, J Am Chem Soc, 130 (2008) 6896.

59 R. Mallipeddi, and L. C. Rohan, Expert Opin Drug Delivery, 7 (2010)

37.

60 P. Mukherjee, R. Bhattacharya, P. Wang, L. Wang, S. Basu, J. A. Nagy,

A. Atala, D. Mukhopadhyay, and S. Soker, Clin Cancer Res, 11 (2005)

3530.

61 M. I. Sriram, S. B. M. Kanth, K. Kalishwaralal, and S. Gurunathan, Int J

Nanomedicine 5 (2010) 753.

62 J. Pelka, H. Gehrke, M. Esselen, M. Tu¨rk,M.Crone,S.Bra¨se, T. Muller,



H. Blank, W. Send, V. Zibat, P. Brenner, R. Schneider, D. Gerthsen, and

D. Marko, Chem Res Toxicol 22 (2009) 649.

63 N. L. Rosi, D. A. Giljohann, C. S. Thaxton, A. K. R. Lytton-Jean, M. S.

Han, and C. A. Mirkin, Science 312 (2006) 1027.

64 P. Mukherjee, R. Bhattacharya, N. Bone, Y. K. Lee, C. R. Patra et al., J

Nanobiotechnol, 5 (2007) 4.

65 H. S. Cho, Phys Med Biol 50 (2005) N163.

66 C. Pitsillides, E. Joe, X. Wei, R. Anderson, and C. Lin, Biophys J, 84

(2003) 4023.

67 X. Huang, I. H. El-Sayed, W. Qian, and M. A. El-Sayed, J Am Chem

Soc 128 (2006) 2115.

68 R. R. Arvizo, S. Bhattacharyya, R. A. Kudgus, K. Giri, R. Bhattacharya,

and P. Mukherjee, Chem Soc Rev 41 (2012) 2943.

69 M. A. El-Sayed, Acc Chem Res 34 (2001) 257.

70 Y. Wang, X. Xie, X. Wang, G. Ku, K. L. Gill, D. Patrick O'Neal, G.

Stoica, and L.V. Wang, Nano Lett 4 (2004) 1689.

71 H. Changseok, P.Miguel, N. Mallikarjuna Nadagouda, S. O. Obare, P.

Falaras, S.M. Patrick Dunlop, J. Anthony Byrne, H. Choi, and D. D.

Dionysiou, Chapter 5, The Royal Society of Chemistry 2013.

72 T. Pradeep, and Anshup, Thin Solid Films 517 (2009) 6441.

Documents

Review of Literatures on Noble Metal Nanoparticles: Properties …shodhganga.inflibnet.ac.in/bitstream/10603/39151/7/07_chapter 2.pdf · Noble Metal Nanoparticles: Properties and