Nanotechnology is science and engineering at the scale of atoms and molecules. It is the manipulation and use of materials and devices so tiny that nothing can be built any smaller.
How small is small?
Nanomaterials are typically between 0.1 and 100 nanometres (nm) in size – with 1 nm being equivalent to one billionth of a metre (10-9 m).
The different types of nanotechnology are classified according to how they proceed (top-down or bottom-up) and the medium in which they work (dry or wet):
- Descending (top-down):Mechanisms and structures are miniaturised at the nanometric scale — from one to 100 nanometres in size —. It is the most frequent to date, especially in electronics.
- Ascending (bottom-up):You start with a nanometric structure — a molecule, for example — and through a mounting or self-assembly process you create a larger mechanism than the one you started with.
- Dry nanotechnolgy :It is used to manufacture structures in coal, silicon, inorganic materials, metals and semiconductors that do not work with humidity.
- Wet nanotechnology:It is based on biological systems present in an aqueous environment — including genetic material, membranes, enzymes and other cellular components
Nanotechnology and nanomaterials can be applied in all kinds of industrial sectors. They are usually found in these areas:
Carbon nanotubes are close to replacing silicon as a material for making smaller, faster and more efficient microchips and devices, as well as lighter, more conductive and stronger quantum nanowires. Graphene’s properties make it an ideal candidate for the development of flexible touchscreens.
A new semiconductor developed by Kyoto University makes it possible to manufacture solar panels that double the amount of sunlight converted into electricity. Nanotechnology also lowers costs, produces stronger and lighter wind turbines, improves fuel efficiency and, thanks to the thermal insulation of some nanocomponents, can save energy.
The properties of some nanomaterials make them ideal for improving early diagnosis and treatment of neurodegenerative diseases or cancer. They are able to attack cancer cells selectively without harming other healthy cells. Some nanoparticles have also been used to enhance pharmaceutical products such as sunscreen.
Air purification with ions, wastewater purification with nanobubbles or nanofiltration systems for heavy metals are some of its environmentally-friendly applications. Nanocatalysts are also available to make chemical reactions more efficient and less polluting.
In this field, nanobiosensors could be used to detect the presence of pathogens in food or nanocomposites to improve food production by increasing mechanical and thermal resistance and decreasing oxygen transfer in packaged products
Nanotechnology makes it possible to develop smart fabrics that don’t stain or wrinkle, as well as stronger, lighter and more durable materials to make motorcycle helmets or sports equipment.
Here are the four major ways in which nanotechnology is changing the future of healthcare:
Nanomedicine applies nanotechnology in healthcare applications such as treatment and diagnostics of various diseases using nanoparticles in medical devices, as well as nanoelectronic biosensors and molecular nanotechnology. Nanomedicine is currently being used to develop smart pills and for treating cancer.
The term ‘smart pills’ refers to nano-level electronic devices that are shaped and designed like pharmaceutical pills but perform more advanced functions such as sensing, imaging, and drug delivery.
Cancer detection and treatment
A key problem with regular chemotherapy and radiation is the damage caused to the body’s healthy cells during the treatment. New nanomedicine approaches are being used in the treatment of skin cancer, which enables efficient delivery of drugs and other therapeutic treatments to specific tumor sites and target cells with low toxic side-effects.
Nanobots are micro-scale robots, which essentially serve as miniature surgeons. They can be inserted into the body to repair and replace intracellular structures. They can also replicate themselves to correct a deficiency in genetics or even eradicate diseases by replacing DNA molecules. This property is still under development.
Nanobots are currently being tested to perform eye surgery, through a microscopic needle inserted into the retina. Surgeons can direct this needle using a specialized magnetic field.
Nanobots can also be used to clear artery blockages by drilling through them. Scientists at Michigan State University and Stanford University have partnered to develop nanobots which contain carbon nanotubes, loaded with a drug that can eat away arterial plaque. This can reduce the risk of heart attacks.
Nanofibers are being used in wound dressings and surgical textiles, as well as in implants, tissue engineering, and artificial organ components.
Scientists are working on developing ‘smart bandages’, which when left on the site, will absorb itself into the tissue once the wound heals. Embedded nanofibres in these smart bandages can contain clotting agents, antibiotics, and even sensors to detect signs of infection.
4. Nanotech-based wearables
The use of cloth-based nanotechnology in healthcare is a new yet popular form of remote patient monitoring. Such wearables have embedded nanosensors in the cloth that record medical data such as heartbeat, sweat components, and blood pressure. It helps save lives by alerting the wearer and medical professionals of any adverse changes faced by the body
Carbon nanotubes (CNTs) are cylindrical molecules that consist of rolled-up sheets of single-layer carbon atoms (graphene). They can be single-walled (SWCNT) with a diameter of less than 1 nanometer (nm) or multi-walled (MWCNT), consisting of several concentrically interlinked nanotubes, with diameters reaching more than 100 nm. Their length can reach several micrometers or even millimeters.
Like their building block graphene, CNTs are chemically bonded with sp2 bonds, an extremely strong form of molecular interaction
- Used in electric wires to reduce losses
- It can replace silicon made transistors as they are small and emit less heat and it can revolutionise electronics
- Can be used in solar cell
Graphene is a one-atom-thick sheet of carbon atoms arranged in a honeycomb-like pattern. Graphene is considered to be the world’s thinnest, strongest and most conductive material – of both electricity and heat. All of these properties are exciting researchers and businesses around the world – as graphene has the potential to revolutionize entire industries – in the fields of electricity, conductivity, energy generation, batteries, sensors and more.
Graphene is the world’s strongest material, and can be used to enhance the strength of other materials. Dozens of researchers have demonstrated that adding even a trace amount of graphene to plastics, metals or other materials can make these materials much stronger – or lighter (as you can use a smaller amount of material to achieve the same strength).
Graphene is the most heat conductive found to date. As graphene is also strong and light, it means that it is a great material for making heat-spreading solutions, such as heat sinks or heat dissipation films. This could be useful in both microelectronics (for example to make LED lighting more efficient and longer lasting) and also in larger applications – for example thermal foils for mobile devices. Huawei’s latest smartphones, for example, have adopted graphene-based thermal films.
Since graphene is the world’s thinnest material, it also extremely high surface-area to volume ratio. This makes graphene a very promising material for use in batteries and supercapacitors. Graphene may enable batteries and supercapacitors (and even fuel-cells) that can store more energy – and charge faster, too.
Coatings ,sensors, electronics and more
Graphene has a lot of promise for additional applications: anti-corrosion coatings and paints, efficient and precise sensors, faster and efficient electronics, flexible displays, efficient solar panels, faster DNA sequencing, drug delivery, and more.
- Environment: Being very small these particles can create environment pollution
- Security: nano particles can be used in devices to capture videos or use as drones to launch offensive attack
- Equity: developing countries have less access to funds to create nanotechnology products
- Ethical:Using nano technology and devices in human beings can create a more powerful human being with enhanced human capabilities..should we pursue them?
- Technical barriers
Issues in India
- No single regulatory body in INDIA
- Insufficient studies on toxicological studies of nanoparticles
- Facilities required for research are less and outdates
- Nanotechnology regulatory board to regulate industrial nano products
- Nano technology institutes like Indian Institute of Nano sciences at Bangalore,Mumbai,kolkata
- Nano technology initiatives program by Department of Information technology and for nano electronic products
- Nano science and technology initiative to promote nano technology which led to Nano mission
- Nano mission:1000 crore allotted for 5 years for development of nano technology
Mission on Nano Science and Technology (Nano Mission):
- Launched in 2007.
- It is as an “umbrella capacity-building programme”.
- The Mission’s programmes will target all scientists, institutions and industry in the country.
- It will also strengthen activities in nano science and technology by promoting basic research, human resource development, research infrastructure development, international collaborations, among others.
- It will be anchored in the Department of Science and Technology and steered by a Nano Mission Council chaired by an eminent scientist.
Outcomes and significance of the mission:
- As a result of the efforts led by the Nano Mission, today, India is amongst the top five nations in the world in terms of scientific publications in nano science and technology (moving from 4th to the 3rd position).
- The Nano Mission itself has resulted in about 5000 research papers and about 900 Ph.Ds and also some useful products like nano hydrogel based eye drops, pesticide removal technology for drinking water, water filters for arsenic and fluoride removal, nanosilver based antimicrobial textile coating, etc.
The Nano Mission has thus helped establish a good eco-system in the country to pursue front-ranking basic research and also to seed and nurture application-oriented R&D, focused on useful technologies and products.