Food Science and Animal Nutrition

1. ASPECTS OF NANOTECHNOLOGY IN FOOD
SCIENCE AND ANIMAL NUTRITION
Dr Rai Dhirendra Prasad
Bihar Veterinary College, Patna,
India
Dr Saurabh Raidhirendra
Prasad
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2. 2
PART I
Science at Nanoscale

3. “The design, characterization, production, and application of structures,
devices, and systems by controlling shape and size at the nanometer”

4. Nanotechnology in Ancient Period
 Ras-Ratnakar: • The first relationship between human life
and nano-scale was developed in Ayurveda, which is about
5000 years old the Indian system of medicine. Ayurveda
described the formation of metallic nanoparticles about 5000
years ago
 Alchemist- • History claims that nanoparticles have been
around us for a long time. Presumably, the use of nanoparticles
was reported in 1570 as aurum potable (potable gold) and Luna
potable (potable silver) which alchemists used as elixirs.
 Dr Samuel Hahnemann- Organon of medicines
 Lycurgus Cup: 4th century AD
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5. History
The idea of nanotechnology
was born in December 29, 1959
when physicist “Richard Feynman”
gave a lecture exploring the idea
of building things at the atomic
and molecular scale. He is regarded as
Father of Nanotechnology and given the
Famous statement “There is plenty of
Room at the bottom”
He imagined the entire Encyclopedia
Britannica written on the head of a pin.

6. Nanomaterilas:
 • The Greek word nano identifies a material whose size has been
reduced to 10-9 m, which is 1000 times smaller than one micron.
 • Structures on a nano scale are considered at the borderline of the
smallest of human-made devices and the largest molecule of a living
system.
 Definition given by The Royal Society and The Royal Academy of
Engineering is “nanotechnology is the design, characterization,
production, and application of structures, devices, and systems by
controlling shape and size at the nano-meter scale

7. Historical Evidences
• History claims that nanoparticles have been
around us for a long time.
• one of the oldest application of nanoparticles
that we come across in literature is the use of
gold Nano particles for staining glasses, a
famous example of which is Lycurgus cup that
dates back to 4th century AD
• The Lycurgus cup contains nanomaterials of
gold and silver and looks jade green in natural
light and on impressive red color when a
bright light is shines through it.
• This is made up of glass that changes color
when light is shone through it.

8. Nanoparticles
 "A particle with the size of the order of 1-nm to 100nm in
any dimension and at least any one property different
from that of bulk".
 During the synthesis of nanoparticles, size of nanoparticles
depends on the steochiometric ratio of metal ion to capping
ligands concentration.
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9. Classification of Nanomaterials
 (a) Classification based upon the origin of nanoparticles: The
nanomaterials can be classified in different ways. One of the ways to
classify nanomaterials is based on their origin.

10. (b) Based upon Dimension
 (1) Zero Dimensional Nanomaterials: In this type of nanomaterial all the
three dimensions lie within the nano range i.e. 1nm to 100nm. Eg molecules, clusters,
fullerenes, rings, metal carbides, powders, grains, etc
 (2) One Dimensional Nanomaterials: In this type of nanomaterial out of three
dimensions two dimensions lie within the nano range i.e. 1nm to 100nm and one
dimension is not within the nano range. Eg. Nanotubes, nanorods, nanowires, fibers,
filaments, whiskers, spirals, belts, springs, columns, needles, etc
 (3) Two Dimensional Nanomaterials: In this type of nanomaterial out of three
dimensions one dimension lies within the nano range i.e. 1nm to 100nm and two-
dimension are not within the nano range. Eg. Layers, nano wells, nanofilms,
nanocoatings
 (4) Three Dimensional Nanomaterials: In this type of nanomaterial all the three
dimensions lie outside the nano range i.e. 1nm to 100nm. In a true sense, these are not
nanomaterials. Eg bulk powders, bulk nanomaterials, dispersion of nanoparticles,
bundles of nanowires and nanotubes as well as multinanolayers.

11. (1) Organic Nanomaterials and (2) Inorganic
Nanomaterials
 Organic Nanomaterials: The organic nanoparticle includes dendrimers,
chitosans, liposomes, micelles, etc. The organic nanoparticles can be used as
drug delivery vehicles. Casein, the milk protein is safe can be used as drug
carrier. It is an alternative for albuminbecause it is inexpensive and has better
amphiphilicity, good dispersibility, and rapid reconstruction in an aqueous
solution.
 Inorganic Nanomaterials: Inorganic nanomaterials have been widely used in
various fields due to their excellent mechanical properties, optical properties,
magnetic properties, electrical properties, catalytic properties, thermal
properties, and sensitivity properties. According to different sources, inorganic
nanomaterials can be classified into two main categories (1) Non- metallic
nanomaterials eg silica-based nanomaterials, and (2) Metallic nanomaterials eg
silver, gold nanomaterials, etc.

12. Nano-composites
 These are a class of nanomaterials wherein one or more phases at nano-
sized dimensions (zero dimension, one dimension, two-dimension) are
embedded in ceramic, metal, or polymer materials. These can be made by
inorganic or organic components at the molecular level to obtain new
properties.

13. Carbon based nanoparticles
 The carbon-based nanomaterials include fullerene, single-walled carbon
nanotubes, and multiple-walled carbon nanotubes. These are a novel class
of nanomaterials that are widely used in biomedical fields including the
delivery of therapeutics, and biomedical applications. Owing to
exceptional structural, mechanical, electronic, and optical properties
carbon nanotubes are regarded as new-generation nanoprobes.

14. Ceramic Nanoparticles
 These are inorganic solids made up of oxides, carbides, carbonates, and
phosphates. These nanoparticles have high heat resistance and chemical
inertness. These nanomaterials can be successfully applied in various ways
such as photo-catalyst, photo-degradation of dyes, drug delivery, and
imaging.

15. Metal Nanoparticles
 Metal nanoparticles are generally synthesized through a bottom-up
approach using precursors of metals. Normally salts of metals are used for
the synthesis of metallic nanomaterials. The metallic nanoparticles are
having high absorption capacity. Therefore, such nanoparticles are widely
used as a catalyst in organic transformation reactions. Apart from catalytic
applications, these nanoparticles have applications in research areas,
detection and imaging of biomolecules, and in the environment and
bioanalytical applications.

16. Semiconductor Nanoparticles
 Semiconductor nanoparticles have properties like those of metals and also
like non-metals. Thus they have intermediate properties. These particles
have a wide bandgap, which on tuning shows different types of properties.
They are widely used as a photo-catalyst, in electronic industries, photo-
optics, and water splitting applications.

17. Polymer Nanoparticles
 Polymeric nanoparticles are organic-based nanoparticles. Depending
upon the method of preparations, these have structures like nano-
capsules or nano-spheres. A nano-sphere particle has a matrix-like
structure whereas nano-capsules particles have core-shell morphology.
The polymeric nanomaterials can protect drugs and control their release
of the drug. They have a wide range of applications in drug delivery and
diagnostics.

18. Food Nanotechnology
 Nano-food‟ can be defined as food that has been produced or
packaged by nanotechnology techniques.
 Nanotechnology for food-packaging aims at reducing ultraviolet
Ultra Violet light exposure or microbial growth.
 Food safety can be improved by Nano-sensors able to detect
pathogens or contaminants.
 Food materials are often considered not only a source of nutrients but
also as having to contribute to the health of consumers.

19. Food Nanotechnology
 Most of the nanoparticles used traditionally belong to the group of
colloids (i.e. emulsions, micelles, mono- and bi-layers).
 In the food industry, several novel applications of nanotechnologies
have become apparent, which include the use of nanoparticles, such as
micelles, liposomes, nano-emulsions, bio-polymeric nanoparticles, and
cubosomes, as well as the development of nano-sensors, which are aimed
at ensuring food safety.

20. Nanotechnology in Food Modulation
 Food in nano form can be better uptaken, and absorbed, and also
bioavailability is higher.
 Nanotechnologists are attracted to develop and commercialize
nano-sized ingredients, supplements, and nutraceuticals.
 Nanotechnology is having an impact on the entire food sector
starting from production, processing, transportation, safety, storage, and
delivery.
 • Nutrients and other additives preparation, structure control, and
encapsulation are applications of nanotechnology in the food industry.

21. Nanotechnology in Food Modulation
 Nano-food is developed to improve food safety, enhance nutrition, and
flavor, and cut costs.
 Bioactive compounds that can be found naturally in certain foods have
physiological benefits and might help to reduce the risk of certain
diseases, including cancer.
 By reducing particle size, nanotechnology can contribute to
improving the properties of bioactive compounds, such as delivery
properties, solubility, prolonged residence time in the gastrointestinal
tract, and efficient absorption through cells.

22. Nanotechnology and Food Science
 Preservatives
 Coloring
 Flavoring and
 Nutrients

23. Nanotechnology and Food Science
Food additives are substances added to food to improve its
 Storage properties
 Appearance
 Flavor and
 Nutritional values

24. Nanotechnology and Food Science
 Nanoceuticals:
 Carotenoids nanoparticles can be dispersed in water and can be added to fruit
drinks for
 improved bioavailability;
 Canola oil-based nano-sized micellar system is claimed to provide delivery of
materials such as vitamins, minerals, or phytochemicals;
 A wide range of nanomedical products containing nanocages or nanoclusters that
act as
 delivery vehicles, e.g., a chocolate drink claimed to be sufficiently sweet without
added sugar or sweeteners;
 . Nanosilver or nanogold is available as mineral supplements;
 To prevent the accumulation of cholesterol some of the nutraceuticals
incorporated in the carriers include lycopene, beta-carotenes, and phytosterols

25. Animal Nutrition: Welcome Nanotechnology
 The application of nanoscience and technology in animal nutrition includes the use of different
nanoparticles in the administration of medications, nutrients, probiotics, supplements, and
other substances.
 In recent years feed additives such as trace minerals in nano forms can be used.
 Application of nanomaterials is currently used for meat and food generally including the use of
NPs and nanomaterials as food ingredients which are placed directly into food or as a part of
packaging materials.
 Nano minerals are having great potential as mineral feed supplements in animals even at very
lower doses than the conventional organic and inorganic sources.
 Silver, Copper, Iron, and Manganese di-oxide are metal nano-composites added to poultry feed.
 Various researchers have described the disease-prevention properties of dietary supplements
such as polyphenols.
 The biological activity of the nanomaterials may be anti-microbial, anti-oxidants, and
prevention and management of some chronic diseases.

26. Nature of Nanomaterials Area of application in animal nutrition
Selenium It significantly decreases ruminant Ph and ammonia concentration. Increases total
VFA concentration linearly and quadratically.
The urinary excretion of purine derivatives was also significantly changed by
improving nano-Se supplementation.
Selenium has a positive effect against peroxide damage in blood components.
The selenium content increases the final weight of an individual.
Selenium nanoparticles blood, serum and tissue selenium concentration, serum
antioxidant enzyme activity.
Nano selenium shows favorable effects on fertility in male goats and shows positive
effects on testicular microstructure, testicular spermatozoa, testicular glutathione
peroxides activity, and semen quality.

27. Nanotechnology in Animal Nutrition
Nanomaterials Area of Application in Animal Nutrition
Copper Nano-copper supplements improved growth performances in piglets.
Significant improvement was observed in IgG, γ- globulin, total globulin protein level,
and SOD activity.
Silver Supplements enriched with nano-silver show anti-microbial activity.
Nano-silver is a growth promoter too.
The concentration of Clostridium perfringens and Clostridium histolyticum group was
reduced in the ilium.
Zinc The nano zinc feed supplements showed improved immune status and bio-availability
in animals.
The ZnO nanoparticles showed to inhibit mycotoxin fungus growth.

28. Properties at nanoscale
 Properties of nanoparticles: depend upon size, shape, electrostatic force
of attraction or repulsion, reaction condition, pH of the medium, time of
contact, stabilizing agent, method of preparation etc.
 The materials at nanoscale often acquires some exotic properties which
are different from that of bulk materials.
 It is observed that the materials sustain their regular physical and
chemical properties up to micrometer level
 Changes in optical, thermal, electrical, electronic, magnetic and
mechanical properties
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29. Thermal properties: Melting Point
 • The thermal properties of
the materials are the properties
that are exhibited when the
material is heated.
 Graph of melting point (Tm) vs
size of particle (D)
 Melting point of nanoparticles is
below the melting point of bulk
material
Tm= TmBulk (1-1/D)
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30. Optical Property
 • Light is the form of energy
detected by the eyes and at an
ordinary scale can be treated as
waves. Light waves are part of
electromagnetic waves.
 Size dependent optical properties of
gold nanoparticles
 This effect appears due to the
interaction of electro-magnetic
radiation with the electron cloud
present on the surface of metal
nanoparticles
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31. Surface Plasmon Resonance
 Surface Plasmon
oscillations.
 Large number of atoms
present on the surface of
nanoparticles contributes
electron cloud which
interacts with E-field of
light and thus oscillates
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32. Electronic Property
 When the size enters nano level, electron motion is
restricted to a smaller space, they don’t follow classical
theory & restricts themselves from diffusion of valence and
conduction band.
 The energy gap between valence band and conduction
bond (Kubo gap) becomes larger than thermal energy
(KBT) and hence metallic nanoparticles become
semiconductor further becomes an insulator
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33. Other Properties
 Magnetic Property: Bulk materials forms multiple magnetic domains, but
nanoparticles form only a single magnetic domain thus could be used for
super magnetism.
 Bio-compatibility:
 Electrical Properties: The metals that are good conductance behave as
semiconductor at nano-level.
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34. Property changes…
 opaque substances become transparent (copper)
 stable materials turn combustible (aluminum)
 insoluble materials become soluble (gold)
 Chemically inert becomes active (Gold)
 Insulators can show electrical conductivity
 Thermal properties eg melting point changes
 Magnetic properties changes
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35. Why different property at Nanoscale ?
• High Surface to Volume ratio (Aspect ratio) : Surface is in stretched
condition resulting in increase in surface energy.Because of this the
nanoparticle become less stable .
 Gravitational force: Due to extremely small size and low mass
gravitational force is ineffective
 Electrostatic force: The electrostatic force of attraction or repulsion
predominates.
 Size comparable to wavelength of light: thus entire different optical
properties like Surface Plasmon Resonance is exhibited.
 Dangling bonds: These are unsatisfied valences tends to quickly form
bonds
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36. Surface to Volume Ratio
 spherical particle,
 surface area = 4πr2 and volume
= 4/3 π r3
 Sp= 4πr2σ/ (4/3)πr3ρ
 Where, σ is surface area factor and ρ is
volume factor
 r→o , Sp→∞
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37. Quantum mechanics
 Nanoparticles do not obey the laws of classical mechanics or Newtonian
mechanics; instead they follow the principles of quantum mechanics.
 Exhibits interesting shape dependence due to electronic motion in
different dimensions.
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38. Example of shape dependent property
 Electronic tunneling phenomenon is observed for 0-D
nanostructures which is the key concept used for building
artificial atoms and devices like single electron transistors.
 Electron can oscillate in two distinct ways in 1-D nanostructures
under electromagnetic field, namely in longitudinal and
transverse modes. The way electrons executes its motion alters
their various properties and thus nano-rods and nano-tubes
give rise to Surface Plasmon absorption peaks due to the two
different types of electronic motion.
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39. Nanoparticles as Smart Material:
 Smart materials are the materials that respond favorably to change in
temperature, pH, conductivity, moisture or electromagnetic fields thus are
extensively used as sensors and actuators. Today smart materials are
widely used as biosensors, chemical sensors etc
 Nanoparticles can also be used as advanced engineering materials which
can withstand high temp, high impact. Such nanomaterials can be used in
smart textiles, technical textiles etc
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40. Nano-composites
 Light weight Nano composites can replace heavy metals in automobile
industry to achieve high speed in vehicles
 Nano-composites can be used as a catalyst in organic transformation
reactions.
 Nano-composites can be used in construction materials.
 Nano-composites are actively used to enhance the efficiency of solar cells,
semi-conducting materials, and also in superconductor and super
capacitors
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42. Norio Taniguchi
 The term "nanotechnology" was defined by Tokyo Science University
Professor Norio Taniguchi in a 1974 paper as follows: "'Nanotechnology'
mainly consists of the processing, separation, consolidation, and
deformation of materials by one atom or by one molecule."
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43. Stabilization of Nanoparticles
 Tendency to form agglomeration: Due to stretched surface, the
nanomaterials have high surface energy and becomes thermodynamically
unstable. Thus, they show tendency to aggloromate so as to acquire
stability.
 Stabilizing agent: usually accomplished by suitable passivating agents also
called as capping agent eg CTAB, polyvinyl alcohols, amino acids,
templates etc.
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44. Gibb’s Free Energy & Stability
 As size of the nanoparticles decreases their surface energy
increases.
 Increase in the surface energy results in increase in the Gibb’s
free energy.
 According to the law of thermodynamics, every system always
tries to attain minimum Gibb’s free energy
 Therefore it loses its nanoness and exotic properties related to
it. Hence it is very important to stabilize the nanoparticles
against the aggregation.
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45. 45
Electrostatic Stabilization

46. Potential energy vs distance between the
nanoparticles
 Particles formed are surrounded by the electronic double
layer of reactant ions on the surface of nanoparticles
 Two forces: Van der Waals forces of attraction , and
electrostatic force of repulsion due to the charged ions on
the surface.
 Stability of nanoparticles is dependent on the combined
effect of these two forces.
 Greater the thickness of the double layer, higher is the
potential energy barrier & higher is stability
46

47. 47
Different Capping agents used for Surface Modification & Stabilization

48. Surface Modification using Capping Agent
 Electron rich ligands such as amines, thiols, phosphates, carboxylates
used for capping of nanoparticles. The capping agents provides stability to
the materials at nanoscale.
 Surface modifications like reactivity, Charge on the surface, specific
gravity, nature of surface i.e. hydrophobicity induced in the nanoparticles
with the help of different capping agents.
48

49. 49
Stabilization by Steric interaction where Electrostatic Force of repulsion
are weak

50. Steric Interaction for Stabilization
 Nanoparticles dispersion in organic medium experiences
less significant electrostatic effects and stability comes from
steric interactions by adsorption of amphiphilic molecules.
 The lead group of these molecules binds with metal
nanoparticles surface while hydrocarbon chain prevents
aggregation sterically as shown in figure.
 Due to these steric interactions, the nanoparticles are
found to be stable in the form of powder even after
complete evaporation of solvent.
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51. Choice of Capping Agent
It determines:
 Stability
 Reactivity
 Size and shape
 e.g. Poly vinyl alcohol
 Stability can be determined as:
 Visualization
 Zeta Potential
 Electron microscopic study
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52. Synthesis Techniques
1) Bottom-up technique
2) Top- down technique

53. 53

54. Methodology
 Adopted method is Chemical route of synthesis and
Biosynthesis using cow urine
 We require reducing and capping agent for synthesis
 Reducing agents are electron donars such as NaBH4, LiAlH4 etc
 Natural reducing agents are anti-oxidants
 Several plants contain anti-oxidant which can act as reducing
agents
 Proteins present in plant may act as capping agent.
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55. Methodology
 Prasad et al developed biosynthesis using Indian cow urine.
 Ayurveda describes the significance of cow urine in medicine.
 The chemical composition of cow urine includes urea, albumin, minerals,
water etc
 Upon the action of enzyme urease or just by heating for particular time,
ammonia can be generated.
 Ammonia can act as reducing agent.

56. Methodology

57. PART II
Biosynthesis Of Nanoparticles

59. Method of Synthesis

60. Why green synthesis?
 To avoid production of
unwanted/harmful by-products
 For reliable and cost-effective
build-ups
 For production of nanoparticles
at large-scale
 3 R’s (Reduce, Recycle, Reuse)
 Controlled morphologies
 Bio-compatible products

61. Biosynthesis:
• Production of chemical compounds
from precursors in living organism.
• Involves enzymes and energy
sources.
• some examples; photosynthesis,
chemosynthesis, amino acid
synthesis, nucleic acid synthesis,
and ATP synthesis.
• The biosynthesis method for
production of nanoparticles have
more effective applications than
physical and chemical synthesis
method, because this method is
reliable, nontoxic, and eco-friendly.
 Nanoparticles are biosynthesized
when the microorganisms grab
target ions from their environment
and then turn the metal ions into
the element metal through enzymes
generated by the cell activities.
 It can be classified into intracellular
and extracellular synthesis
according to the location where
nanoparticles are formed.
 The organisms used for synthesis of
nanoparticles are bacteria, fungi,
yeast.

63. 1. Bacteria:
 Bacterial species have been widely
utilized for commercial
biotechnological applications such as
bioremediation, genetic engineering,
and bioleaching.
 Bacteria possess the ability to reduce
metal ions and are momentous
candidates in nanoparticles
preparation . For the preparation of
metallic and other novel
nanoparticles, a variety of bacterial
species are utilized.
 Prokaryotic bacteria and
actinomycetes have been broadly
employed for synthesizing
metal/metal oxide nanoparticles.
2. Fungi:
 Fungi-mediated biosynthesis of
metal/metal oxide nanoparticles is also a
very efficient process for the generation
of monodispersed nanoparticles with
well-defined morphologies.
 They act as better biological agents for
the preparation of metal and metal oxide
nanoparticles, due to the presence of a
variety of intracellular enzyme .
 Competent fungi can synthesize larger
amounts of nanoparticles compared to
bacteria. Moreover, fungi have many
merits over other organisms due to the
presence of enzymes/proteins/reducing
components on their cell surfaces.
 The probable mechanism for the
formation of the metallic nanoparticles
is enzymatic reduction (reductase) in
the cell wall or inside the fungal cell.

64. 3. Yeasts:
 Yeasts are single-celled
microorganisms present in
eukaryotic cells. A total of 1500 yeast
species have been identified.
 Successful synthesis of
nanoparticles/nanomaterials via
yeast has been reported by
numerous research groups.
 The biosynthesis of silver and gold
nanoparticles by a silver-tolerant
yeast strain and Saccharomyces
cerevisiae broth has been reported.
4. Plants:
• Plants have the potential to accumulate
certain amounts of heavy metals in their
diverse parts. Consequently, biosynthesis
techniques employing plant extracts have
gained increased consideration as a simple,
efficient, cost effective and feasible methods
as well as an excellent alternative means to
conventional preparation methods for
nanoparticle production.
• There are various plants that can be utilized
to reduce and stabilize the metallic
nanoparticles in “one-pot” synthesis
process.
• Many researchers have employed green
synthesis process for preparation of
metal/metal oxide nanoparticles via plant
leaf extracts to further explore their various
applications.

65. Green synthesis of silver nanoparticles
using Gongura leaf extract

66. PART III
Uses of Nanoparticles

67. Ayurveda and Unani uses of nanoparticles :
 In Sanskrit, Ayurveda means ‘ the science of life ’.
 Ayurveda is supposed to be originated from Atharvaveda.
 Ayurveda is the oldest form of Indian traditional system of
medicine. The other traditional system of Indian medicine
includes Unani and Siddha.
 Ayurveda aims at strengthening the capacity of the body and
improving immunity by using herbs, animal products and
minerals in its medicines.
 whereas Unani, which is the holistic system of medicine, is
quite common throughout the India.
 A section of Ayurveda deals with herbo-mineral preparations
called Bhasma (ash) is known as Rasa Shastra (Vedic
chemistry).

68.  The major therapeutic actions of Bhasma are their ability for
Immunomodulation and anti-aging property (Rasayana) and ability to
target drugs to the site.
 Ayurvedic preparations are claimed to be nontoxic, absorbed readily, and
biocompatible.
 Bhasma is an important Ayurvedic formulation comprising mixture of
herbs and metals.
 Bhasma are nearer to nanocrystallite materials which are solid composed
of crystallite with sizes less than 100 nm, at least in one dimension.
 Ayurvedic metallic nanocrystallite or Bhasma have unique
physicochemical properties such as biocompatibility and ease of surface
fictionalization.

69.  The nanotechnology in Ayurvedic drugs have application in:
1. molecular detection
2. targeted delivery
3. biological imaging.
 application of Nano-carriers for the delivery of Ayurvedic drugs can be a
great initiative because such carriers are capable to cross the plasma
membrane and deliver the drug in the desired concentration at the
specific site of action. Integration of Ayurveda and nanotechnology may
provide the best medicines to treat various life-threatening diseases.
 Nanoparticles are used in various sensors such as Gas sensors, Chemical
sensors, artificial tongue, humidity sensors etc

70. Attributes of Nanotechnology
 Nanoparticles are used in solar cell devices
 Nanoparticles are used in memory storage devices such as memristers
 Nanoparticles are in super-capacitors to store electrical energy
 Nanoparticles are in electrochromic materials
 Nanoparticles are used in the area of veterinary and human medicine.
Today we observe that efficiency of antibiotics against a pathogenic
bacterium gets decrease after frequent uses. It is difficult to have new
antibiotics. It has been observed that many nanoparticles especially silver
nanoparticles show high antimicrobial activities.

71. PART IV
Environmental Aspects Of
Nanoparticles

72. POSITIVE IMPACT OF NMs
Nanotechnology promises significant social, environmental, and financial benefits. Nanotechnology may
ultimately be developed to help decrease the human footprint on the environment by providing more
efficient and energy saving innovations.

73. NEGATIVE IMPACT OF NMs
As the environmental impacts of NMs cannot be clearly diagnosed and there are too many variables to
account for (e.g., NMs identification, low detection limits, and unknown environmental concentrations), it
is very difficult to reach any conclusion about the ecological effects and environmental stability of NMs.
Even a minor change in the chemical structure of NMs could radically change their properties, turning them
into toxic compounds. According to the United States Environmental Protection Agency, “the toxicity of
NMs is difficult to identify because they have unique chemical properties, high reactivity, and do not
dissolve in liquid”

74. Analysis of Materials at Nanoscale
 The nanomaterials are so small that they cannot be visualized by naked
eyes.
 The properties of materials at nanoscale depends upon size, shape,
morphology, interatomic distance, electrostatic forece of attraction or
repulsion, secondary bonds like van der waal’s interaction etc.
 It is possible to determine the properties of the materials at nanoscale
using advanced characterization techniques such as XRD, Scanning
Electron Microscopy, Transmission Electron Microscopy, Zeta Potential
etc.

75. Characterization Techniques
 . The instruments used for analysis are of two types i.e. 1) spectroscopes
and 2) microscopes.
 A. Spectroscopy: It is a branch of science that deals with the interaction
of electromagnetic radiations with the matter. Spectroscopy is the most
powerful tool available for the study of atomic and molecular structure
and is used in the analysis of a wide range of samples.
 B. Microscopic Techniques
 Microscopy is the technical field of using a microscope to view samples
and objects that cannot be seen with the unaided eye. There are three
well-known branches of microscopy; optical, electron, and scanning
probe microscopy.

76. Characterization Techniques
 Optical and electron microscopy involve the diffraction, reflection, and
refraction of electromagnetic radiation/ electron beam interacting with
the specimen and the subsequent collection of this scattered radiation or
another signal to create an image. This process may be carried out by
wide-field irradiation of the sample (e.g. Transmission Electron
Microscope) or by scanning a fine beam over the sample (e.g. Scanning
Electron Microscope).

77. Characterization Techniques

78. UV-Visible Spectroscopy
 UV-visible spectroscopy is used for the measurement of the intensity of
absorption in near-ultraviolet and visible radiation by a sample.
 Ultraviolet and visible radiation ranges in wavelength from 200 nm to 800
nm and is energetic enough to promote outer electrons in an atom to
higher energy levels.
 UV-visible spectroscopy is useful for qualitative and quantitative analysis
of the sample.
 Moreover, UV-visible spectroscopy can also be used to determine the band
gap of semiconductors.


79. XRD

80. XRD
 X-rays are invisible, highly penetrating electromagnetic radiations of much
shorter wavelengths than visible light.
 X-rays are electromagnetic radiations with a wavelength of the order of 10-10 m.
 Van Lave demonstrated in 1912 that X-rays could be diffracted by crystal. Later,
in 1935 Le Galley first constructed an X-ray powder diffractometer. They are
typically generated by bombarding a metal with high-energy electrons.
 The high-energy electrons must penetrate through the outer electron shells and
interacts with the inner shell. If more than a critical amount of energy is
transferred to an inner-shell electron, that electron is ejected i.e. it escapes the
attractive field of the nucleus, leaving the hole in the inner shell and generating
an ionized atom.

81. FT-IR Spectroscopy

82. FT-IR Spectroscopy
 Infrared spectroscopy is a common spectroscopy technique used to
identify the chemical functional groups present in the sample.
 It is an excellent tool to study the interactions and mechanisms of the
reduction of metal ions.
 Spectroscopy in the middle IR region is extremely useful for the study of
organic compounds.
 IR spectroscopy has been widely used for the identification of organic
compounds because their spectra are generally complex and provide
numerous maxima and minima that can be used for comparison purposes.

83. Microscopic Techniques

84. Scanning Electron Microscopy
 This is a type of electron microscope that produces images of a sample by
scanning it with a focused beam of electrons.
 The electrons interact with the atoms in the sample, producing various
signals that can be detected and that contain information about the
sample’s surface topography and composition.
 The electron beam scans in a raster scan pattern, and the beam’s position
is combined with the detected signal to produce an image.
 Scanning electron microscopy is extremely useful for direct observations
of the surface because they offer better resolution and depth of field than
optical microscopes. The SEM shows very detailed 3-D images at a much
higher magnification than is possible with a light microscope.

85. Transmission Electron Microscope

86. Transmission Electron Microscope
 Working Principle: TEM is a microscopic technique in which a beam of
the electron is transmitted through an ultra-thin specimen, interacting
with the specimen as it passes through.
 An image is formed from the interaction of the electrons transmitted
through the specimen; the image is magnified and focused onto the
imaging device such as a fluorescent screen.
 In TEM analysis, a thin specimen is illuminated with electrons in which
the electron intensity is uniform over the illuminated area.
 As the electrons travel through the specimen, they are either scattered by
a variety of processes or they may remain unaffected by the specimen.

87. Brief Bio-data
 Dr. Rai Dhirendra Prasad: He has completed degree in Veterinary science
and Animal Husbandry from Bihar Veterinary College, Patna, India
which is one of the oldest veterinary college of India. This is the 5th
college established in undivided India. After completion of the
educational program Dr. Prasad joined department of Animal Husbandry
government of Maharashtra where he served on various posts at different
places. He rendered his services for several years in tribal area of
Maharashtra, India. He is having high expertise in technical subjects like
animal anatomy, animal nutrition and animal biochemistry. He is having
vast direct clinical exposure where he treated various animal diseases. He
is having expertise in treating trypanosoasis. Then, he tried to study effect
of Homeopathic medicines for critical animal diseases.