It consists of introduction about nano world and how it is different from the macroscopic world and what are the reasons. it gives information about silver nanoparticles antimicrobial property and it is various application. it consists of synthesis, characterisation of silver nanoparticles.

1. ANTIMICROBIAL
SILVER NANOPARTICLES

2. Contents
INTRODUCTION
BULKTO NANO……
WHYSILVER?........
PREPARATION
PROPERTIES
CHARACTERIZATION
APPLICATIONS

3. INTRODUCTION
TO
NANO

4.  Nanotechnology is a discrete field which has emerged as a
dynamically developing area of scientific interest in the world.
This modern research dealing with design, synthesis and manipulation
of particle structures ranging from approximately
1-100nm.
 Nanoparticles are defined as a Nano scale particle of size ranging
form 1 to 100 nm
Application of metal nanoparticles is the versatile fields like, catalyst,
electronic, magnetic, mechanic, optical optoelectronic, materials for
solar cell and fuel cell, medical, bio imaging, cosmetic, ultrafast data
communication and optical data storage, etc, is increasing their value.

5. NANO
Vs
MACRO

6. :
 Increase in surface area, where higher
number of atoms can sit which is not in
case of bulk.
 Simply properties of materials change as
a function of size of the particle.

7. At nano scale the gold losses its vibrant yellow colour.
 Light gets reflected from the surface of the gold at bulk state, the
electron clouds resonates with certain wavelength of light at nano scale.
Depending of the size of the nano particle, it absorbs light of certain
wavelength and emits light at different wavelengths
90nm  abs: ( red to yellow)
 emits ( blue-green)
30nm  abs: (blue and green)
 emits (red)
 Increased surface-to-volume ratio. The changes is the bulk
properties(mp, bp, hardness, etc) can be attributed to the enhanced
Surface-to-Volume ratio of nanoparticles.
Quantum confinement i.e., electrons are not freely movable in bulk
material rather they are confined in space. Size tunable electronic
properties of nanoparticles arise due to quantum confinement.

9.  Enhanced physico-chemical properties.
High electrical and thermal conductivity
High stability
than the other noble metals such as gold and platinum
Wide absorption of visible and far IR region of the light
Chemically stable
Enhanced catalytic activity
They exhibit a broad spectrum of high antimicrobial activity(bactericidal
and fungicidal activity) attracting the scientists and technologists to
develop nano silver-based disinfectant products.

10. SYNTHESIS

11. PHYSICAL
METHOD
CHEMICAL
METHOD
BIOLOGICAL
METHOD
ELECTROCHEMICAL,
ULTRA SONICATION,
LASER ABLATION,
IRRADIATION,
EVAPORATION,
CONDENSATION
CHEMICAL
REDUCTION,
SOL-GEL
BACTERIA,
FUNGI,
YEAST,
PLANT EXTRACTS

13. NANO RODS
NANO WIRES

14. CHARACTERISATION
 UV SPECTRUM
 SEM/TEM IMAGE
XRD ANALYSIS
FTIR SPECTRUM

17. Anti microbial property
of
Silver nanoparticles

18.  Increased in the large surface area enhanced the interaction with other
particles and increases their antimicrobial efficiency.
One gram of Ag NPs is required to give antibacterial properties to
hundred of square meters of substrate material.
All bacteria, virus, and fungi use and enzyme as a form of chemical lung
in order to metabolize oxygen.
The AgNPs cripple the enzyme and stop the take up of oxygen.
This effectively suffocates any bacteria, virus, fungi, killing it within 6
minutes and leaving surrounding tissue or material unaffected.
 Surface immobilized nanoparticles show greater efficacy than colloidal
AgNPs as well a higher concentration of silver ions in solution.
 E.coli cells treated with AgNPs in the bacteria cell wall , there is a
formation of “pits” in the cell walls eventually leading to cell death.
The antibacterial activity of AgNPs is not only size but also shape
dependant.
AgNPs undergo a shape-dependent interaction with Gram-negative
organism E.coli.

19.  The antibacterial effect of AgNPs on Gram-negative bacteria was stronger
than Gram positive bacteria.
The negative charge in the bacteria cell membrane due to presence of
carboxyl ,phosphate and amino groups.
The positive charge confers electrostatic attraction between AgNPs and
negatively charge cell membrane of the microorganisms which facilitates
AgNPs attachment onto cell membrance.
Hence, enhanced antibacterial effects can be obtained by altering the
surface charge of AgNPs to achieve stronger attractive force.
AgNPs can kill various pathogens like salmonella typhi, Bacillus subtilis, K.
pneumonia etc., and those which cannot killed by the other antimicrobial
agents.

20. DISK DIFFUSIONMETHOD
AND
ZONE OF INHIBITION

23. Textiles and clothing
Surface coating
Food preservation
Purified drinking water
Wastewater treatment
Health supplements
Household items(e.g., washing machines, deodorants
detergents

25. 23%
77%
NANOMARKET
SILVER NANOPARTICLES
OTHER MATERIALS
53%
10%
10%
6%
4%
3% 2%
12%
LIFE USE
HEALTH
CLEANING
FOOD
HOUSE HOLD EQUIPMENTS
MEDICINE
ELECTRONIC DEVICES
TOYS

26. APPLICATIONS
OF
SILVER NPs
TEXTILES
UV Blocking Textiles
Anti-stain Textiles
Medical Textiles
BIOMEDICAL
Cancer therapy
Diagnosis
Drug delivery
Cell imaging
ENVIRONMENTAL
Water disinfection
Activated Carbon
filters
Wastewater
Treatment
CATALYSIS
Fuel cell catalyst
Fuel additive catalyst
Hydrogen production
photo catalysts
HEALTH CARE
UV protection
Topical ointment &
Creams
nutraceutical
FOOD AGRICULTURE
Food packing
Interactive food
Food quality analysis
sensors

27. THANK YOU