nanotechnology in drug delivery and diagnostic
Published on: Mar 3, 2016
Transcripts - nanotechnology in drug delivery and diagnostic
DRUG DELIVERY AND
Drug delivery refers to approaches, formulations, technologies,
and systems for transporting a pharmaceutical compound in the
body as needed to safely achieve its desired therapeutic effect.
For example protein and peptide drugs have to be delivered by
injection(daily life) or a nanoneedle
Diagnosis is the identification of the nature and cause of a certain
WHY NANOTECHNOLOGY IN DRUG
DELIVERY AND DIAGNOSTIC ?
• (i)Targeting, to increase the drug concentration
at desired sites of action and reduce systemic
levels of the drug and its toxic effects in healthy
• (ii)Improved solubility
• (iii)Constant rate of drug delivery, resulting in
zero-order release kinetics to maintain a constant
therapeutic dose at the site of action .
• (iv)Increased drug stability, to reduce
degradation and maximize drug action.
• (vi)Drug delivery across the blood–brain barrier
NANOMATERIALS USED IN DRUG
DELIVERY AND DAGNOSTIC
Nanotechnology on chip (biochip, protein chips)
These are surface perforated with holes
and in nano dimensions . for example,
be created by a pore-forming protein
or as a hole in synthetic materials such
as silicon or graphene.
Desai and his co workers fabricated tiny
chambers si wafer in which biological
cell can be placed .
Small molecules like oxygen, glucose
and insulin can pass through these
pores but large molecules such as Ig’s
and graft borne virus particles cannot
pass and this process is called
• A fullerene is any molecule composed entirely of
carbon, Spherical fullerenes are also called
buckyballs . Fullerenes are similar in structure to
graphite, which is composed of stacked graphene
sheets of linked hexagonal rings; but they may
also contain pentagonal rings.
• C60(type of fullerene) is commonly used in drug
delivery due to its good bio compatibility and low
• Against several diseases like parkison’s and HIV .
• ANTI VIRAL AGENTS for eg USED IN HIV
• Anti cancerous
• A nanoparticle are sub micron sized
polymeric colloidal particle with a therapeutic
agent of interest encapsulated within their
polymeric matrix or adsorbed or conjugated
on to the surface
• Highly versatile system ,overcome
physiological barriers and guide the drugs to
specific cells .control release pattern of drug
and drug level for long time.
• Anticancer drug loaded nanoparticles are
mainly concentrated in kuffer cells in liver .
• These are spherical polymeric molecules
formed through nanoscale hierarchical Self
assembly process. These are the
macromolecule, which is characterized by its
highly branched 3D structure that provides a
high degree of surface functionality and
versatility. Dendrimers have been refered to
as the “Polymers of the 21st century.
• Liposomes are spherical self-closed
structures , composed of lipid bilayers
, which enclose part of the
surrounding solvent into their interior.
• Can incorporate both hydrophobic
and hydrophilic drugs in them.
• Liposomes are used in the diagnostic
imaging by using contrast agent .
• Lipoplexes are the nanostructure(net
positive charge) which have the
cationic liposomes with polyanionic
plasmid DNA .it is used in the gene
targeting to liver .
Nanoshell is a type of
consisting of a dielectric core
which is covered by a thin
metallic shell usually gold
coated silica .
These are used for early
detection of cancer and its
treatment by embedding drug
containing tumor targeted
hydrogel polymer and injected
in the body .which when
heated with laser
(infrared)and thus release drug
at tumor site .
Nanorobotics is the emerging technology
field creating machines or robots whose
components are at or close to the scale of
a nanometer (10−9 meters).
Nanorobots can be used in the
biomedical field .
Nature already provides nanorobots in
human body for e.g .lymphocytes
,fibroblasts ,neutrophils etc
Nanorobotics will allow doctors to
perfrom direct in vivo surgery on
individual human cell.
Its exterior shape consists of diamondoid
material, to which may be attached an
artificial glycocalyx surface that minimizes
fibrinogen adsorption and bio activity
ensuring sufficient biocompatibility to
avoid immune system attack.
• Targeted drug delivery is a method of delivering
medication to a patient in a manner that increases the
concentration of the medication in some parts of the
body relative to others and reducing the side effects.
• Two approaches are –passive and active targeting
• In Passive drug targeting accumulation of drug is at
particular site due to physicochemical or
• In active drug targeting employs specific modifications
of drug/drug carrier nanoystems with active agents
having selective affinity for recognizing and interacting
with a specific cell,tissue or organ in the body .
Nanosensors with immobilized bioreceptors
probes that are selective for target analyte
molecules are nanobiosensors. they
integrated into other technologies such as
lab-on-chip or biochips /protein chips.
PEBBLE NANOSENSOR (probes encapsulated
by biological localised embedding ) Probes
Encapsulated By Biologically Localized
Embedding (PEBBLEs) are isolated nanoscale
devices for intracellular chemical analysis.
This schematic shows a generalized view of an
ideal PEBBLE with many options for
encapsulated constituents. In the examples
that follow, it will become clear how this
technology allows us to probe the nanoscale
chemical and biological world.PEBBLE sizes
can range from 20 to 200 nm in diameter.
It is used in early detection of cancer .
Optical biosensors used in diagnostic by
using surface plasmon resonance technology
• Surface plasmon resonance technology(SPR)
• It is an optical electrical phenomenon involving the
interaction of light with the electrons of the metal
• Photon of light transfer its energy to group of
electrons(plasmon)at the surface of metal
• ELECTRONIC NANOBIOSENSORS – It works by
electronically detecting the binding of a target DNA
molecule to a sensor on a microchip.
Principle of immunoassays:
• Reactions between two protein molecules can
be extremely specific.
• One type of molecule (antibody) can be
immobilised on gold sensor surface.
• The second (antigen) will bind changing the
refractive index .
• This change is detected by changed angle of
surface plasmon resonance.
Gold nanoparticles are attached onto DNA or
an antibody or other molecule instead of
flurosencent molecule which assemble on a
sensor surface only in the presence of a
These are particularly good labels for sensors
because a variety of analytical techniques
can be used to detect them, optical
absorption, fluroscence ,raman scattering,
atomic and magnetic force.
This can be use to detect microorganism and
could replace pCR and flouroscent tag.
Raman active dyes are attach on to DNA
which attach to gold nano particle. Since
raman band is narrower than the floroscence
band it allowa more dyes to detect more
targets quickly .these particles easily
prepared ,they have very low toxicity.
Submicrometer metallic barcodes with
striping patterns prepared by
sequential electrochemical deposition
of metal ions. These particles make
them useful for bioanalytical
The differential reflectivity of adjacent
stripes enables identification of the
striping patterns by conventional light
Biobarcode assays are an ultra senstive
method for detecting proteins analytes
relies on magnetic microparticle probes
with Ab that specifically bind the target
of interest and nano particle probes
that are encoded with DNA that is
unique to protein target of interest and
A quantum dot is a nanocrystal made of
semiconductor materials that glow when
excited by a light source at any wavelength
from infrared to visible to ultraviolet.
They can be specifically attached to
biological materials such as cells , proteins
and nucleic acids making them powerful
Advantages of QD technology are :-high
-availability of IR/red colours enables whole
-fluorescence is stable
-highly resistant to degradation
Major challenge is that QDs have an oily
Used for diagnose genotyping ,white blood
assays, multiplexed diagnostics
Magnetic nanoparticle are a class of nanoparticles
which can be manipulated using magnetic field. Such
particles commonly consist of magnetic elements
such as iron, nickel and cobalt and their chemical
They can be used to label specific molecule,
structures ,m/o’s .these labelled magnetic
nanoparticles get changed their magnetic field when
come in contact with the analyte and which is
detected by sensitive magnetometer .
these can be used for the detection of circulating
cancer cell in the blood and isolation of m/o’s such as
bacteria useful for curing serious infection.
Ferrofluid consists of magnetic core surrounded by
polymeric layer coated with antibodies for capturing
cells .they are colloidals when mix with the sample
containing target cells ,Ab conjugated to the magnetic
core bind the Ag associated with the target cells
For eg used for the telomerase activity in the
biological sample ,MRI
NANOTECHNOLOGIES IN DRUG
DELIVERY AND DIAGNOSTICS
AFM(ATOMIC FROCE MICROSCOPY)
SPR(SURFACE PLASMON RESONANCE )
SERRS ( SURFACE ENHANCED RESONANT
RAMAN SPECTROSCOPY )
• RESONANCE LIGHT SCATTERING TECHNOLOGY
ATOMIC FORCE MICROSCOPY
• AFM is used for diagnostic and
cytogenetics investigation of
biochemical and structural
properties of human
• AFM have been used to obtain
information from chromosomal
probes. the final resolution
allows a more precise
localization compared to
standard techniques ,and the
extraction of very small
amounts of chromosomal DNA
by scanning probe is possible.
DEVELOPED BY concentris
•These are the small beams used to screen
biological samples for the presence of
particular genetic SEQ. the surface of each
cantilever is coated with DNA that can bind
to one particular target seq
•On exposure of the sample to beams ,the
surface stress bends the beams by appx 10
nm to indicate that the beams have found
the target in the sample.the surface stress
results in minute deflections of the
cantilevers and these deflections correlated
directly to the conc of the target substance
•Used for the detection of disease by breath
analysis e.g presence of
•It requires no labels ,optical excitation
,external probes and is rapid ,highly
specific ,sensitive and portable.
APPLICATION OF NANODIAGNOSTICS
Use of nanocrystals in immunohistochemistry
Glucose monitoring in vivo by nanosensors
Detection of disease biomarkers
Detection of single nucleotide polymorphisms
Detection of disease genes
Detection of microrganisms such as bacteria
• Treatment of diseases such as cancer ,eye
problems, joints problems etc .