An introduction to future drug delivery system

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.
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 successfully
Killed tumor cells while leaving neighboring cells intact.
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.
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.
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 of
Certain trigger molecu;es associated with cancer.following drug releases the dendrimers may
Also report bacj whether they are successfully killing their targets.
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.
Recent advances in nanothechnology in cancer Treatment:
1) 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.
2) 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 and
Eliciting 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.
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 pancreatic
Cancer 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.
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 organ
Regeneration Nevertheless the complexity of biological systems poses a significant challenge in
Developing CNT-based tissue tissue engineering applications ali khorramdust focuses on the
Recent 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.waterDispered 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
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 average
Velocity and diffusion coefficient of the vesicles containing NPs were 10.2(+/-1.8) microm/hr
And 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 this
Phenomenon 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 cell
Through a microelectrode: electrical characteristics of the cells were measured with the electrode
And transfer of the dye from the single cell to its neighbours by cell-to-cell gap junctions was
Observed 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 Impedence
Sensing (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

similar documents