nanomaterials, Anti-microbial agents, types, uses and disadvantages

2. TABLE OF CONTENTS
1. Introduction to nanoparticles
2. Types of nanoparticles
3. Characterization of nanomaterials
4. Mode of Action
5. Test used to determine the antimicrobial
properties
6. Antimicrobial activity of nanoparticles
7. Antiviral and antifungal studies on
nanoparticles
8. Applications of nanoparticles
9. Advantages of nanoparticles
10.Disadvantages of nanoparticles
11. In MnP curation

3. MULTIPLE DRUG RESISTANCE (M D R)

4. NOVEL DRUG DELIVERY SYSTEM (N D D S)
• Approaches, formulations, technologies and systems for transporting a pharmaceutical compound in the
bodyasneededto safelyachieveitsdesiredtherapeuticeffect

5. INTRODUCTION TO NANOPARTICLES
• NanoderivedfromtheGreekword“nanos”,meaningdwarfor extremelysmall
• A nanometeris a billionthof a meteror 10¯⁹m
• Solidcolloidalparticlesrangingfrom1 – 1000nmin size
• Small,truncatedtriangularnanoparticleswithlargersurfaceto volumeratios-strongest biocidalaction

6. Matrix type structure in
which the drug is dispersed
Membrane wall structure and
an inner core containing the
drug
TYPES OF NANOPARTICLES
Nanotubes

7. 1. CHEMICAL
• Precipitation
• Sol-gel method
• Solvothermal synthesis
2. PHYSICAL
• Laser ablation
• Ultrasonication
3. BIOLOGICAL
• Plant extracts
• Bacteria
• Fungi
PREPARATION OF NANOPARTICLES

8. EXAMPLES OF NANOMATERIALS
 Silver nanoparticles
 Gold nanoparticles
 Magnesium oxide nanoparticles
 Copper oxide nanoparticles
 Aluminium nanoparticles
 Titanium dioxide nanoparticles
 Zinc oxide nanoparticles

9. CHARACTERIZATION OF NANOMATERIALS
 Spectrophotometry: to check the concentration of
nanoparticles in the solution
 X-ray diffraction experiments: shape characteristics
 Field emission scanning electron microscopy: morphological
analysis
 Transmission electron microscopy: particle size distribution

10. ANTIBACTERIAL ACTIVITY
OF NANOPARTICLES
1. Directly interacts with the microbial cells by
a. Interrupting trans-membrane electron transfer
b. Disrupting or penetrating the cell envelope
c. Oxidizing cell components
2. By producing secondary products
a. Reactive oxygen species
b. Dissolved heavy metal ions

11. Cell membrane
disruption
Protein
Cell membrane
DNA damage
Ag(I)
Zn(II)
Release of heavy
metal ions
Mitochondria
damage
Interrupted transmembrane
electron transport
Reactive oxygen
species (ROS)
ROS production
MODE OF ACTION OF NANOPARTICLES (NPs) AGAINST BACTERIA
Oxidized cellular
component

12. MODE OF ACTION OF NANOPARTICLES ON
GRAM POSITIVE BACTERIA

13. MODE OF ACTION OF NANOPARTICLES ON
GRAM NEGATIVE BACTERIA

14. TEST USED TO DETERMINE THE
ANTIMICROBIAL PROPERTIES
AGAR DISK DIFFUSION METHOD
• Culture both gram positive and negative bacteria on LB agar medium
• Pour liquid Mueller Hinton agar (pH 7.3 ± 0.2 at 25 °C) onto disposable sterilized Petri dishes
• Allow to solidify; dry surfaces of solidified agar plates in incubator
• Place the microbial culture over the surface of agar plates
• Spread uniformly using sterilized glass rod
• Dry the plate surface
• Apply nanoparticle loaded disks to the surface of the seeded agar plates using sterile forceps
• Incubate for 24 hrs at 37 °C
• Measure the zone of inhibition

15. ANTIVIRAL STUDIES OF NANOPARTICLES
• Undeveloped area
• Metal NPs- as anti-viral systems taking advantage of the core material and/or the ligands shell
• Ag nanoparticles - against HIV-1 at non-cytotoxic concentrations
• exert anti-HIV activity at an early stage of viral replication
• prevent CD4-dependent virion binding, fusion, and infectivity-act as an virucidal agent
against both cell-free virus and cell-associated virus

16. ANTIFUNGAL ACTIVITY OF METAL NANOPARTICLES
• Limited studies on the antifungal activity of metal nanoparticles
• Nano-Ag exhibit potent activity against clinical isolates and ATCC strains of Trichophyton
mentagrophytes and Candida species
• Antifungal activity of nano-Ag-effects on the mycelia
• Application in biostabilization of footwear materials

17. APPLICATIONS OF NANOPARTICLES
• Broad spectrum antimicrobial activity - bandages, catheters
and other materials to prevent infection (healing of wounds
and burns)
• Household products such as bedding, washers, water
purification systems, tooth paste, shampoo, fabrics, deodorants
• Titanium dioxide nanoparticle - cosmetics, filters that exhibit
strong germicidal properties and remove odors, and in
conjunction with silver as an antimicrobial agent

18. • Titanium dioxide- self cleaning and self-disinfecting
material for surface coatings in many applications and in
food industries for disinfecting equipments
• Photo catalytic activity - waste water treatment
• Zinc oxide (ZnO) and copper oxide nanomaterials-
antimicrobial property- medical and skin coating
• ZnO nanoparticles- wallpapers in hospitals as
antimicrobials

19. ADVANTAGES OF NANOPARTICLES
• Unlike other antibiotics, NPs do not alter the resistance of the microorganisms since they are
more specific
• Nanoparticle drug carrier : higher stabilities
• Particle size and surface characteristics easily manipulated to achieve both active and passive
drug targeting after parenteral administration
• Biodegradable, non-toxic and stored for longer periods
• Used for controlled delivery of drugs

20. DISADVANTAGES OF NANOPARTICLES
• Highsystemicexposureto locallyadministereddrugs
• Nanotoxicity(lung,kidney, liver,brain,germcell, etc)
• Requireshighlysophisticatedtechnologyforthe formulation
• Requiresskillformanufacturing,storageandadministration