Download - Nano Biotechnology Final Ppt
What is Nanobiotechnology?
Nanobiotechnology usually refers to the useof nanotechnology for biological purpose.
An area of scientific technology that appliesthe tools and processes of Nanotech to builddevices for studying bio systems.‐
Nanobiotechnology incorporatesbiotechnology on the nano scale.‐
SCIENCE OF ULTRA SMALL
Generally nanotechnology deals with structuressized between 1 to 100 nanometre.
It involves developing or modifying materials ordevices within that size.
Nanomaterials are commonly defined asmaterials with an average grain size less than 100nanometres.
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Why Do Properties Change?
Three important ways in which nanoscale materialsmay differ from macroscale materials :
1 Gravitational forces become negligible andelectromagnetic forces begin to dominate .
2. Greater surface to volume ratios
3. Random molecular motion.
Note: By patterning matter on the nano scale, it ispossible to vary fundamental properties ofmaterials without changing the chemicalComposition:
NANOPARTICLE
Nano particle usually forms the core of nano‐ ‐biomaterial.
It can be used as a convenient surface formolecular assembly, and may be composed ofinorganic or polymeric materials.
Nanoparticles are of great scientific interestas they are effectively forming a bridgebetween bulk materials and atomic andmolecular structures.
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Hybrid NanoparticlesThey are composed of two or more kinds of materials in
nanoscale (1nm=10-9m), that are visible only with an electron
microscope and prepared for a specific function.
One example is lipid polymer hybrid Nanoparticles where
the positive attributes of both liposome's and polymeric
Nanoparticles are combined into a single delivery system.
Sometimes they are nanostructures—in which tiny magnetic
particles are stuck to other particles to form complexes that
resemble dumb bells or flowers shaped.
Nanoscale devices smaller than
50 nm can easily enter most cells, and
20 nm can move out of blood vessels ,as they circulate through the
body.
They can be in the form of
Nanospheres - matrix systems in which drugs are
dispersed throughout the particle,
Nanocapsules - drug is confined in an aqueous or oily
cavity surrounded by a single polymeric membrane.
Other example:
Gold and iron oxide hybrid nanoparticles (HNPs)
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NANOPARTICLE HYBRID(Lipid polymer hybrid Nanoparticles)
This type of nanoparticles is typicallycomprised of three distinct functionalcomponents:
1. A hydrophobic polymeric core where
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poorly water soluble‐ drugs areincorporated with high loading yields.
2. A lipid layer surrounding the core thatacts as a molecular fence to promoted t ti i id th l i
3. A hydrophilic polymer layer outside thelipid shell to enhance nanoparticlestability and systemic circulation lifetime.
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ADVANTAGE OF USING NANOPARTICLE HYBRID
Nanoparticles with a size range of 10 150 nm are highly‐beneficial and favourable for systemic drug delivery.
The morphology and the core shell structure of the hybridnanoparticles can be measured by electron microscopy.
Steric repulsive force in hybrid nanoparticles is provided byPEG molecules on the nanoparticle surface.
Both PEG chain length and lipid/lipid PEG molar ratio havesignificant impact on nanoparticle stability.
The lipid shell is expected to prevent small drugmolecules from freely diffusing out of the polymer core,thereby improving drug loading yield.
It also reduce water penetration rate into the polymercore, thereby decreasing the rate of polymer degradationand slowing down drug release from the particles.
A shell around the core particle enable a controlledrelease of drug or may protect from a toxic impact.
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Hybrid nanoparticles offer numerousadvantages:
a) Drug delivery platform including simple fabricationprocess,
b) Tunable size and surface,c) High loading capacity of poorly water soluble drugs,‐d) Sustained and controllable release profile of the drugs,e) High in vitro stability, andf) Excellent in vivo properties.g) Targeted drug delivery.h) Deliver two or more drugs simultaneously for
combination therapy to generate synergistic effects.
Some other examples of Hybrid nanopartiles:1.“Nano-flowers” , so named because of their petal-like arrangement ofodd-shaped iron oxide particles around a core of spherical shaped goldparticles.
2 “Nano-olives”• Spherical nanoparticles, with basically the same shape, and composed
of an inner core of one material and an outer core of another,• Composed of iron, platinum, and oxygen — have slightly different
internal compositions that are impossible to detect under a microscope.
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Nano-flower Nano-olives
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3.Gold-nanoparticle−CaCO3hybrid material (AuNP−CaCO3)
Gold nanoparticles (AuNPs) were assembled on the surface of porous
calcium carbonate microspheres(CaCO3) in a neutral aqueous
solution through electrostatic interaction.
Characteristics
a. Size at nano scale 1-100nm range,
b. Encapsulation efficiency,
c. Surface charge, and
d. Release characteristics.
Special formulations like albumin-based,
carbohydrate-enhanced, or fatty acid targeting
have also been used.
AuNP−CaCO3
Gold –
Material key to fight cancer in smart therapies.
Is biocompatible, inert and relatively easy to weak chemically.
By changing the size and shape of the gold particle, it can be tuned to
respond to different wavelengths of energy.
Cells can take up gold nanoparticles without cytotoxic effects.
Advantage that when are exposed to infrared light, they melt and
release drug payloads attached to their surfaces.
Iron oxide –
Is basically rust
Allow to track the progress of cancer treatments using magnetic
resonance imaging by taking advantage of the particles' magnetic
properties.
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Nanotechnology in medicine
Nanotechnology in Medicine has these thrust areas:
1. Drug Delivery2 Therapy techniques 3. Diagnostic and Imaging Techniques4. Anti Microbial Techniques‐
Nanotechnology in medicine The use of nanotechnology in medicine offers some exciting
possibilities. Some techniques are only imagined, while others are atvarious stages of testing, or actually being used today.
Nanotechnology in medicine involves applications of nanoparticles
currently under development, as well as longer range research thatinvolves the use of manufactured nano-robots to make repairs at thecellular level (sometimes referred to as nanomedicine).
Nanotechnology is already being used as the basis for new, more
effective drug delivery systems and is in early stage development asscaffolding in nerve regeneration research.
In Cancer area also there is a hope that investments in this branch of
nanomedicine could lead to breakthroughs in terms of detecting,diagnosing, and treating various forms of cancer.
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How nano particles delivery can become specific?
In various approaches, nanoparticles systems are linked
with materials that respond to stimuli such as temperature,
pH, light, electromagnetic waves, enzymatic activity or
other biological markers as Stimuli-responsive materials
They have been created by using biological, physical and
chemical properties of materials for heat-activated, light-
activated or pH-activated delivery.
What are the problems in using nano particles?
Hybrid particles are especially challenging because the methods that are
used to make them often leave impurities that are not easily detected or
removed.
Impurities can change the properties of a sample, for example, by
making them toxic, so it is a big challenge to find ways to remove such
impurities.
Other challenges - specifically to use within biological systems.
Smaller nanoparticles may be cleared by body too rapidly that it can’t
be effective in detection or imaging.
Larger nanoparticles may accumulate in vital organs, creating a toxicity
problem.
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Smart Drug Delivery (Targeted drug delivery)
Is a method of delivering medication to a patient in a manner that helps to
concentrate the medication in the tissues of interest while reducing the relative
concentration in the remaining tissues.
It aims to deliver the active therapeutic ingredients to the disease site in stable
compartments as an encapsulated nanoparticle system , by facing challenges as
Stabilization Extended Circulation Targeting
The goal of a targeted drug delivery system is
More specific drug targeting and delivery, Greater safety and biocompatibility, No higher dose than needed, Reduction in toxicity while maintaining therapeutic effects Prolong and a protected drug interaction with the diseased tissue.
Traditional drug delivery systems involves:
Oral ingestion or intravascular injection of drug,
Drug is distributed throughout the body through the systemic blood
circulation,
Only a small portion of the medication reaches the organ to be
affected and
Absorption of the drug across a biological membrane takes place.
Therapeutic drug administration :
At high concentration
Repeated amounts when the distribution is non-selective
Prolonged period of time to a targeted diseased area within the body
Drawback - Side-effects
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There are different types of drug delivery vehicles, such as
polymeric micelles, liposome, nano-particle drug carriers ,dendrimers
etc.
An ideal drug delivery vehicle must be
a. Non-toxic,b. Biocompatible,c. Non-immunogenic andd. Biodegradable.
Nanoparticles have properties such as
a. Large surface area,b. High drug loading efficiency andc. Potential combination with other organic/inorganic
materials.
Nanoparticles can be designed by attaching to polyethylene glycol (PEG)
or other types of polymers to provide a hydrophilic environment, thereby
shielding them from immune recognition .
Surface functionalization of nanoparticles with PEG resulted in efficient
internalization in endosomes and cytosol, and localized in the nuclear
region.
Nanodevices are suitable to serve as customized, targeted drug delivery
vehicles to carry of chemotherapeutic agents into malignant cells while
sparing healthy cells, greatly reducing or eliminating the side effects that
accompany many current cancer therapies.
Its an excellent candidate for imaging guided therapy, in medical
applications .
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Nanoparticle-based delivery systems offer the following
Advantages
Site-specific delivery of drugs, peptides, and genes ,
Improved in vitro and in vivo stability
Reduction in the frequency of the dosages ,
More uniform effect of the drug,
Reduction of drug side effects, and
Reduced fluctuation in circulating drug levels.
Disadvantage
High cost which makes productivity more difficult and
Reduced ability to adjust the dosages.
'Smart' nanoparticles used in cancer
A gold hybrid nanoparticle that, identify, target and kill specific cancer cells
while leaving healthy cells alone.
Shaped something like a dumbbell -- made of gold sandwiched between two
pieces of iron oxide
They then attached antibodies that target a molecule found only in cancer
cells to the particles. Once bound, the nanoparticles are engulfed by the cancer
cells.
To kill the cells the researchers use a near-infrared laser which is a
wavelength that doesn't harm normal tissue at the levels used, but the radiation
is absorbed by the gold in the nanoparticles. This causes the cancer cells to
heat up and die. This is a so-called “smart' therapy”.
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Nanotechnology in Medicine Application: Therapy
Techniques
Buckyballs may be used to trap free radicals generated during an allergicreaction and block the inflammation.
Nanoshells may be used to concentrate the heat from infrared light todestroy cancer cells with minimal damage to surrounding healthy cells
Nanoparticles, when activated by x-rays, that generate electrons thatcause the destruction of cancer cells to which they have attachedthemselves. This is intended to be used in place of radiation therapy with
h l d t h lth ti
Aluminosilicate nanoparticles can more quickly reduce bleeding intrauma patients by absorbing water, causing blood in a wound to clotquickly.
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Nanotechnology in Medicine Application: Diagnosticand Imaging Techniques
Quantum Dots (qdots) may be used in the future for locating cancer tumors in
patients and in the near term for performing diagnostic tests in samples,
although at this time the use "in vivo" (in a living creature) is limited to
experiments with lab animals. Concerns about the toxicity of the material that
quantum dots are made from is one of the reasons restricting the use of
quantum dots in human patients. However, work is being done with quantum
dots composed of silicon, which is believed to be less toxic than the cadmium
contained in many quantum dots.
Iron oxide nanoparticles can used to improve MRI images of cancer tumors. The
nanoparticle is coated with a peptide that binds to a cancer tumor, once the
nanoparticles are attached to the tumor the magnetic property of the iron oxide
enhances the images from the Magnetic Resonance Imagining scan.
Application of nanoparticles of biological origin in
their natural or in a modified form as antibacterials.
The first example involves an additional application of electrospun
thenanofiber mats; however in this case they were spun from thepolysaccharide chitosan.
Polymers with intrinsic bacteriostatic and/or bactericidal activity and, in
particular, polysaccharides are considered as promising for wound healing‐
and dressing applications.‐
The natural polysaccharide chitosan was reported to possess
advantageous biological properties, such as hemostatic activity, nontoxicity,
biodegradability, intrinsic antibacterial properties and the ability to affect
macrophage function, which contributes to faster wound healing
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