Nowadays we always hear the word nanotechnology or nanotechnology. However, not everyone is familiar with nanotechnology, but in today's world, our daily lives are largely dependent on nanotechnology. It may seem strange to many, but it is true. When I came to the United States in 2010 to study nanotechnology, I had no idea. Even today, nanotechnology is a myth to most people in Bangladesh. In fact, it is not at all. Examples of nanotechnology are at our fingertips. Believe me, I'm not exaggerating. Our mobile phones are actually the contribution of nanotechnology. How? I'm explaining.
If we go back to about 70 years ago today, the invention of the 'transistor' is the beginning of electronics nanotechnology. Transistor means but not radio (many people in Bangladesh used to know radio as transistor). Transistors are just one of the key components of making a radio. One transistor, discovered in 1948, was about the size of a fist. That means its length was a few centimeters. Similarly, the first computer, Iniac, required about 16 square meters of space. But radio, television, phone, calculator and many other things can be operated with a single mobile phone today. Modern mobile phones or smartphones (such as the iPhone) are used to make 2 billion or two hundred million tiny transistors. These are so small that they cannot be seen even with a conventional optical microscope. These are seen through specially made electron-microscopy instruments. The length of each of these transistors is 20 nanometers. One nanometer means one billionth of a meter or one billionth of a billion.
The fact that we are able to work on such a small scale, which has made our modern life more sophisticated, is the contribution of nanotechnology. And substances that have become equal to or greater than the nanometer-scale of our known material (centimeter-scale or its larger volume, such as transistors) are called nanomaterials or nanomaterials. Since these are tiny particles, they are also called nanoparticles.
We understand that nanoparticles are much smaller অনেক the equivalent of atoms. How small is that small? Suppose you are standing just outside the earth trying to see a football lying somewhere on the surface. Again, standing on a football, trying to find the first discovered nanoparticle Fullerene — these two things are the same.

The evolution of the mobile phoneThe evolution of the mobile phoneBecause, the ratio of the diameter of a fullerin and a football is equal to the ratio of the diameter of a football and the earth. This spherical fullerene is made up of 60 carbon atoms, meaning it is a molecule with a diameter of 0.6 nanometers. A water molecule, which is a combination of oxygen and two hydrogen atoms. Its diameter is 0.25 nanometers. But we are saying that fullerene is not a molecule but a nanocan. But why? This is because fullerene is not a liquid, but a tiny solid or particle. There are several such particles, which are made from carbon. Such as Carbon Nanotube and Graphene. Nano particles are also made from different metals. Such as gold, silver, platinum etc.
Now the question is why are we so concerned about nanoparticles? These particles show much different uses than the common substances we know. For example, carbon nanotubes are harder than iron. Under normal circumstances, we mean pencil lead, which is not the case at all. It is even thought that one day a ladder from the earth to the moon could be made with carbon nanotubes. But that day is still far away. Again, many consider it a fantasy. What is happening now is no less. Cyclists take part in the 2006 Tour-of-France (World Cup of Bicycle Racing) with light yet durable bicycles made of these carbon nanotubes.
We do not use gold for any purpose, except for ornaments. If we think about why gold is so expensive, we will see that the main reason is that gold is a very inert substance. It does not change with time or weather. They do not react with any chemicals. The funny thing is that the color of the nano gold is not golden, but a little purple. In addition, with the change in their size in the range of 1-100 nanometers, the color also starts to change. Nano gold reacts for the same reason, in many cases they act as influencers in the reaction. Because of these properties, nano gold is often used in the treatment of cancer. They act like tiny missiles. If they can be properly made and inserted into the body, they can go into the blood vessels, tissues and cells of the body to find tumors. We then see that tumor through MRI or CT scan. Then they can destroy nano gold.