An introduction to future drug delivery system - PowerPoint Presentation

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An introduction to future drug delivery system

Maede

kohi

The prefix ‘

nano

’ comes from the Greek word ‘

nanos

’ meaning ‘a

dwarf’.Hence,’nanotechnology

’

Might well simply mean a technology to do with ‘small’ things

Nanotechnologies are the

design,characterization,production

and application of structures

The size range of interest between a few nanometers and 100 nm is one where many interesting

Things happen.

They can easily transferred through blood vessels and interact with targeted tumor-specific

Proteins both on the surface of and inside cancer cells.

Inadequate drug concentrations reaching the

tumor,and

the limited ability to monitor

therapeuti

Responses.poor

drug delivery to the target site leads to significant complications.

Nanotechnology and

nanomedicine

has exploited the possibility of designing tumor-targeted

Nanocarries

able to deliver radionuclide payloads in a selective manner to improve the efficacy

And safety of cancer imaging and therapy.

The major

nanocarries

include

nanopores,carbon

nanotube,nanoparticles,dendrimers,quantum

Duts,liposomes,and

…

.

Nanotubes:Nanotubes

are smaller then

nanopores

.

About half the diameter of a molecular of DNA also help to identify DNA changes

associiated

With cancer cells.

It helps to exactly pin point location of the

changes.mutated

regions associated with cancer are

First tagged with bulky

molecules.using

a

nano

tupe

tip,resembling

the needle on a record player

The physical shape of the DNA can be

traced.a

computer translates this information into

Topographical map.

Quantum Dotes(QD):

These are tiny crystals that glow when these are stimulated by ultraviolet light.

The latex beads filled with these crystals when stimulated by

light,emiit

the color that lights up

The sequence of interest.

serving as sort of spectral bar code.

Nanotube:

Quantum Dots:

Nanoshells(NS):These are another recent invention.NS

are miniscule beads coated with gold.

The most useful

nanoshells

are those that absorb near infrared light that can easily penetrate

Several centimeters in human

tissuses.Absorption of light by

nanoshells creates an intense heat that is lethal to cells.In laboratory cultures the heal generated by the light-absorbing nanoshells

has successfullyKilled tumor cells while leaving neighboring cells intact.

Liposomes:Liposomes are self-assembling spherical closed colloidal structures composed of lipid bilayers

That surround a central aqueous space.

Liposome based formulations of several anticancer agents have been approved for the

Treatment of metastatic breast cancer and Kaposi’s sarcoma.

Liposomes

:

Nanoshells

:

Caltilevers:

Tiny bars anchored at one end can be engineered to bind to molecules associated with cancer

It would be possible to tell whether the cancer molecules are present and hence detect early

Events in the development of cancer cells.

Dendrimer:

A number of nanoparticles that will facilitate drug delivery are being developed.It is hoped

dendrimers can be manipulated to release their contents only in the presence ofCertain trigger molecu;es

associated with cancer.following drug releases the dendrimers may

Also report

bacj

whether they are successfully killing their targets.

Nanopores

:

Nanopores

(holes)allow DNA to pass through one strand at a time hence DNA sequencing can

Be made more efficient.

The passage of DNA through a

nano

pore can be used to decipher the encoded information

Including errors in the code known to be associated with cancer.

Cantilevers:

Dendrimers

:

Nanopores

:

Fluorescent Nanoparticles:

The diagnosis and treatment of cancer have been greatly improved with the recent

Developments in nanotechnology one of the promising

nanoscale

tools for cancer diagnosis is

Fluorescent

nanoparticles(NPs) such as organic dye-dope NPs quantum dots and upconversion

NPs that enable highly sensitive optical imaging of cancer at cellular and animal level. Monoclonal antibodies and Nanobodies

:In the past decades the mainstay of systemic therapy for solid and haematology

malignancies Was chemotherapy nevertheless this modality has the drawbacks such as drug resistance andEliciting sever cytotoxicity in normal tissue.

The therapeutic monoclonal antibodies(

mAbs

) are deemed to be a class of novel agents that

Can specifically target and disrupt molecular pathways underlying

tumorigenesis.the

mAbs

are

Produced by a single clone of B-cells and are

monospecific

and homogeneous.

The recombinant antibodies have been reduced in size rebuilt into multivalent molecules

And fused with different

moities

such as

radionuclides

toxins enzymes.

Focuses on implementation of the

mAbs

and

nanobodies

fragments for cancer therapy.

Recent advances in

nanothechnology

in cancer Treatment:

3)Nanomedicine:Nanothechnology

has been extensively merging into biomedical research to develop a new

Research field

Nanomedicine

.

The effects of

gastrin messenger RNA(mRNA) down-regulation on growth of human pancreaticCancer

Gastrin expression was examined in human pancreatic cancer cell lines by reverse Transcriptase-polymerase chain reaction and peptide expression was assessed by immunocytoche

mistery Gastrin

was down-regulated using either stable transfection of an antisense gastrin

cDNA

Or 1 of 3

shRNA

(short hairpin RNA) constructs Stable

transfection

in

gastrin

antisense or

shRNAs

Into BxPC-3 cells resulted in clones with more than 90% reduction in

gastrin

mRNA

Immunofluorescence

analysis confirmed that

gastrin

peptide levels were decreased in antisense

And

shRNA

tumors.

4)

Nanomicelles

:

Emerging nanotechnology has already developed various innovative

nanomedicines

Self-assemblies of block copolymers are promising

nanomedicines

for targeted drug delivery and

Imaging stimulus-responsive targeted

nanomicelles

are designed to release drugs on based on

Stimuli such as PH temperature

redox

potential magnetism and ultrasound.

5)Carbon Nanotubes:A vast majority of applications are based on CNTs raging from miniaturized biosensors to organRegeneration Nevertheless the complexity of biological systems poses a significant challenge in

Developing CNT-based tissue

tissue

engineering applications

ali

khorramdust focuses on theRecent developments of CNT-based tissue engineering where the interaction between living

Cells cells/tissues and the nanotubes have been transformed into a variety of novel techniques.

Functional analyses of water-dispered carbon

nanohorns with antitumor activity were Performed to explore their potential as drug carrier for local cancer chemotherapy.water-

Dispered

carbon

nanohorns

were prepared by adsorption of polyethylene glycol-doxorubicin

Conjugate(PEG-DXR) onto oxidized single-well carbon

nanohorns

(

oxSWNHs

).PEG-DXR bound

Ox SWNHs were administered

intratumorally

to lung cancer-cell NCI-H460-bearing mice.

In vitro studies showed that

carboplatin

-filled CNTs inhibited growth of bladder

cacer

cells

Whereas unfilled opened CNTs barely affected cancer cell growth

6)Gold Nanoparticles:Nanotechnology has used to provide advanced biomedical research tools in diagnostic imaging

And therapy which requires targeting of

nanoparticles

(NPs) to individual cells and

subcellular

Compartments.

Results show that the cellular uptake of gold NPs is dependent on their size and surface property

The NPs were transported in vesicles of 300-500 nm diameter within the cytoplasm.the averageVelocity and diffusion coefficient of the vesicles containing NPs were 10.2(+/-1.8) microm

/hrAnd microm 2/hr respectively Analysis of the time dependent intracellular spatial distribution of

The NPs demonstrated that they reside in lysosomes within 40 minutes of incubation.7)Radioprotection by

nanoparticles

:

Radiolysis of water generates a series its radical decomposition products that inactivate

Enzymes and damage cellular lipids proteins and DNA

postirradiation

protection is another

Approach to reduce or reverse deleterious effects after exposure to ionizing radiation

Fullerenes (C60) diminished toxicity of radiation on zebra fish embryos by reducing generation

Of reactive oxygen species

fulleronols

(C60[OH]X) protected unicellular eukaryotes organisms

Against gamma radiation Cerium oxide

nanoparticles

(

nanoceria

) increased longevity of cells by

Reducing hydrogen peroxide and ultraviolet radiation induced injury

Autoregerative

reaction

Cycle Ce3+↔Ce4+ occurs on the surface of the ceria

nanoparticles:changing

oxidation state

From Ce3+ to Ce4+ might scavenge free radicals produced by radiation.

Monitoring toxicity in real time using novel impedance technique:Interaction of mammalian cells with surfaces and focus on the kinetic aspects of thisPhenomenon is of great for science Cell attachment is an important parameter to assess cancer

Cell potential for metastasis and tumor healing caused by their dynamic interaction with

Sabstrates

and drugs.

Cell-to-cell communications were studied by injecting a dye

lucifer

yellow to a single cellThrough a microelectrode: electrical characteristics of the cells were measured with the electrodeAnd transfer of the dye from the single cell to its

neighbours by cell-to-cell gap junctions wasObserved in cell monolayers. The method that applies external electrical field to sense cell

Spreading upon artificial surfaces in real time is referred to as Electric Cell-substsate

ImpedenceSensing (ECIS)Although the ECIS technique has been first described by Giaever and

Keese

Measurements using ECIS of repopulation of mechanically disrupted cells in culture have been

As well suggested as wound healing

assey

.

The ECIS technique is becoming a well-

stablished

technique to study chemical and physical

Factors and other dynamic processes.

Concentration to achieve 50% inhibition was determined in fibroblast V79 cells for free metals

And quantum dots: around 6µM for

Cd

98µM for Zn 154nM for red

CdSe

/

ZnS

240

nM

for green

Cd

/

ZnS

. For the cadmium

selenide

and telluride quantum dots toxicity could be assigned to

Release of free

cadmium.for

quantum dots and gold

nanoparticles

were not toxicity 200nM and

45µM.