3. 1. INTRODUCTION TO NANOMEDICINE
The field of ‘Nanomedicine’ is the science and technology of
diagnosing, treating and preventing disease and traumatic injury, of
relieving pain, and of preserving and improving human health,
using molecular tools and molecular knowledge of the human body
The emerging discipline of nanomedicine brings nanotechnology
and medicine together in order to develop novel therapies and
improve existing treatments.
In nanomedicine, atoms and molecules are manipulated to produce
nanostructures of the same size as biomolecules for interaction with
human cells.
4. 2. BACKGROUND
The prefix “nano” derives from the Greek word for dwarf. One nano-meter (nm)
is equal to one-billionth of a meter, or about the width of 6 carbon atoms or 10
water molecules
A human hair is approximately 80,000 nm wide, and a red blood cell is
approximately 7000 nm wide.
Atoms are smaller than 1 nm, whereas many molecules including some proteins
range between 1 nm and larger.
The term “nanotechnology” was first coined in 1974 by Norio Taniguchi, a
researcher at the University of Tokyo.
5. 3. METHODOLOGY
Current applications of nanotechnology involve drugs, drug delivery, gene therapy cell therapy, and cancer diagnosis and
therapy
Two examples of nanodrugs that seek to disrupt malignant processes are cyclic peptides and molecular nano-generators.
1. Cyclic peptides
Cyclic peptides contain altered specific amino acids that allow them to insert themselves into a foreign bacterial
membrane and self-assemble into a nanostructure.
The nanostructure disrupts the bacteria's cellular functioning, killing it in the process.
6. 2. Molecular nanogenerator
A molecular nanogenerator is a cage of molecules surrounding a single radioactive atom.
An antibody is attached to the nanogenerator to direct it to cancer cells.
When the nanogenerator reaches a cancer cell the radioactive atom inserts itself into the cell and breaks down to
release radiation, which kills the cell
7. 4. APPLICATIONS
1. Quantum dots (Q dots):
Q dots are tiny crystal particles which grow when stimulated by ultraviolet radiation and used to detect cancer and
identify the location of cancer cells in the body
Mechanism:
Wavelength or colour of the emitted visible light from the Q dots depends on
the particle size.
Scientists can design quantum dots that bind to sequences of DNA that are
associated with the disease
When the quantum dots are stimulated with light, they emit their unique bar
codes, or labels, making the critical, cancer-associated DNA sequences visible.
They can be used in the body, eliminating the need for biopsy
8. 2. Nanoparticles
Nanoparticles attach to cells affected by various diseases and allow a lab to identify disease
Nanoparticles also deliver chemotherapy drugs directly to cancer cells to minimize damage to healthy cells.
Nanoparticles used in medicine as:
Contrast agents for medical imaging
Therapeutics for treating cancer
In vivo and In vitro biomedical research and applications.
Diagnostic devices,
Analytical tools,
Physical therapy applications, and drug delivery vehicles.
9. Mechanism:
The Nanoparticles such as nano shells are placed in the bloodstream of a patient with a cancerous tumour, and
because of the leaky characteristics of a tumour’s blood vessels, the nanoparticles accumulate in the tumour and
frame it.
Subsequent exposure to a near-infrared laser generates heat and bursts the cancer cells’ walls.
The light is harmless, and because the heating is localized, it affects only cells immediately adjacent to the nano
shells, and destroys cancerous cells without harming healthy surrounding tissue.
The nano shells eventually are eliminated safely from the body
10. Nanoparticulate technology can prove to be very useful in cancer therapy
It can be used for effective and targeted drug delivery by overcoming the many biological, biophysical and
biomedical barriers that the body experiences during standard intervention such as the administration of drugs or
contrast agents .
Some nanoscale delivery devices, such as dendrimers (spherical, branched polymers), Nano shells, ceramic
nanoparticles, and cross-linked liposomes can be targeted to cancer cells
11. 3. Nanotubes
Nanotubes are carbon rods about half the diameter of a molecule of DNA, help to identify DNA changes associated
with cancer.
Nanotubes also used in broken bones to provide a structure for new bone material to grow
Nanotubes have the following features:
Can detect the presence of altered genes and pinpoint the exact
location of those changes.
Seek out specific mutations in the DNA and bind to them.
Trace physical shape of DNA
Pinpoint mutated region
Creates a map showing DNA molecules, including the tags
identifying important mutations
These techniques will be important in predicting disease.
12. 5. ADVANTAGES:
• Drug delivery at the exact
location
• Lesser side effects, high
efficacy
• Molecular targeting by nano
engineered devices
• Detection/ Diagnosis of
diseases relatively easy and
fast
• No surgery required
• Diseases can be easily cured
6. DISADVANTAGES:
• Not practical yet.
• High cost.
• Implementation difficulties
• Nanotoxicity
13. 7. CONCLUSION:
Although realization of the full potential of nanomedicine may be years or decades
away, recent advances in nanotechnology-related drug delivery, diagnosis, and drug
development are beginning to change the landscape medicine.
The possibilities are endless, but will take time to develop. Nano therapies could, in
the long term, be much more economical, effective and safe and could greatly
reduce the cost of current medical procedures
.
So, Nanomedicine is the future medicine.