How are nanobots defined? What makes them different from nanoparticles or even proteins?

Thank you for this question! Finally someone who might understand that “nanobot” is basically a popular buzzword that has little to no real meaning!

I guess people have idea of nanobots as small robots moving individual molecules/atoms. This idea has been popularized by some sci-fi books, movies, shows.

The idea of “nanobot” is based on the fact that we have seen molecular devices being used in cells (how some things are operated in unicellulars, like “flagelum”). We realized that some molecules offer “moves” conformation upon charge redistribution, upon illumination… So that we know that we can make moving parts on molecular level.

But of course sci-fi authors took this idea and forgot about details. Like quantum mechanics, like thermodynamics…

So…

Nanoparticle is a small piece of “normal” material. An atom/molecule has some properties. That average if you have huge quantity of that material. (An silicon atom has different properties then silicon chunk.) Sure, you must now get the idea that if you have two atoms, they will behave similar to one. Three atoms might start to show more differences… And there must be some “grey” area where you have no more behaviour typical for individual atoms, but you have not yet the behaviour of huge chunk. That is the realm of nanoparticles.

Thanks to this they allow us to have materials and properties based on those effects that emerge only at the boundary of molecules and bulk.

A protein… is basically a nanobot. If we ever produce nanobots they will be quite similar in a lot of things to how proteins, RNA, DNA things work. The similarity will be about the same as knives are similar to claws or teeth. One is natural thing, the other is man made, but for the same purpose. but both need to deal with the same problems.

For more details visit @ https://www.quora.com/How-are-nanobots-defined-What-makes-them-different-from-nanoparticles-or-even-proteins 

What are the sources of nanoparticles?

For clear understanding, the term “nano” is one billionth of one. So any material with dimension of 1cm, reduced into a billion equal parts in any dimension, then one part is 1 nanometer (nm). Particles ranging from 1 nm to 100nm are considered as nano materials.

By sources, do you mean where can we find nano materials! The answer would be “Entire universe” because our universe is nothing but chemically composed matter/antimatter. Atoms of every element are less than the nm range.

How do we make them ?

There are many number of methods and techniques to make nanomaterials. Divided into two basic techniques namely Physical and Chemical techniques attributed to the methods they use in exfoilation or growth of nano materials.

There is also other approaches to make nano materials; Top-down and Bottom-up approaches.

As the name suggests, in Top-down approach, bigger particles are reduced into nano particles by the usage of physical and chemical techniques and Bottom-up approaches makes use of nanomaterials to make bigger materials using chemical and physical techniques.

The application area of nanomaterials are unlimited ranging from electronics, optics, mechanics, communications, biological, medical, pharmaceutical, physical training, energy, storage, battery, water purification, DNA science, etc. This potential for nanomaterials is achieved due to their peculiar change in physical and chemical properties in due to but not only their change in size and surface area.

Reference:https://www.quora.com/What-are-the-sources-of-nanoparticles

What is a nano carbon?

Natural carbon can exist in two very different types and is know to everyone: graphite and diamond. Three additional forms of carbon that were discovered between 1985 and 2004 have caused the current excitement among researchers about carbon nanomaterials – fullerenes, nanotubes, and graphene. 

See here for details:  https://www.quora.com/What-is-a-nano-carbon

What makes carbon nano tube gives such strength?

Carbon nano tubes are considered as one of the strongest material when mixed with a matrix material like epoxy and polymer to form nano composites. Their structural strength or load bearing capacity is even multiple times higher than structural steel if properly fabricated. The most important property which nanocomposites possess is their very high strength to weight ratio. Strength to weight ratio is a very important parameter in composite technology to rate composite on the basis of their structural properties. Also, depends on the stacking sequence, carbon nano tubes gives excellent structural properties in different-different arrangement of its layers in composites like unidirectional arrangement, bi-directional arrangement, skew arrangement etc.

 

Reference: https://www.quora.com/What-makes-carbon-nano-tube-gives-such-strength

What is the difference between nanomaterials and nanoparticles? What is a carbon nanotube considered as?

All nanoparticles are nanomaterials, but not all nanomaterials are nanoparticles.

Nanoparticles are particles within a nanometer size range. Typically this is in the 10 - 999nm range, with things at the lower end being large molecules or macromolecules (such as many proteins) and at the larger end becoming microparticles (1000 - 100,000 nanometers, or 1 - 100 micrometers / um).

Nanomaterials can have broad definitions. For instance, if you have knowledge of the packing structure of different atoms comprising some form of a metal alloy, you are gaining insight into the structure of the metal at the nanomaterials level.

Another example of nanomaterials that are not nanoparticles is transistors and most of your computer’s hardware. Each transistor is on the order of ~10 nanometers, but it is not a nanoparticle (someone may argue this point :) ).

Nanoparticles can be biological, such as those used for gene or drug delivery applications in FDA/clinical applications, or non-biological such as the titanium and zinc nanoparticles in some sunblocks. They can be made of metals, proteins, genes, ceramics, or any range of materials that are normally found in the world. However, they are constrained to being in a particle format within certain size ranges as opposed to being a more solid matrix with some form of nanostructure (nanomaterials).

You can, also, include nanoparticles within solid matrixes such as ceramics and buildings to modulate their properties.

Carbon nanotubes *can* be used to make nanoparticles. Nanoparticles can be spherical, oblong, tube-like, or any shape you can imagine. However, carbon nanotubes are very, very thin. Depending on whether they are single-, double- or multi-walled, their thickness can range from 2 - 9.5nm (Single, Double, MultiWall Carbon Nanotube Properties & Applications). An aggregate of carbon nanotubes or a 9.5nm x 50nm carbon nanotube would be considered a nanoparticle.

Reference: https://www.quora.com/What-is-the-difference-between-nanomaterials-and-nanoparticles-What-is-a-carbon-nanotube-considered-as

How are carbon nano tubes helpful in defense field?

Carbon nano tubes due to its excellent multi-directional properties basically related to mechanical and electrical engineering make it very popular for some of the most advanced technological applications in the field of aircrafts and defense industry.

In a typical aircraft, there may be thousands of complex parts and all of them need to work efficiently during the operation. So, it is very cumbersome process to inspect each and every thing before each flight as preflight inspection schedule. But, anyhow pilots have to do this. Here come the use of Carbon nano tube. Transparent carbon nano tubes are a way better solution in this regard.

Aircraft wings are also one of the complex parts to inspect because it has several moving parts which results in more number of joints and more possibility to be faulty frequently. So, proper inspection of them is also a vital factor. So, here also transparent carbon nano tubes are best solution not only for transparency but also for good material and structural properties needed for an aircraft wing.

Reference: https://www.quora.com/How-are-carbon-nano-tubes-helpful-in-defense-field

How are nanoparticles used in nanomedicine removed from the body?

Nanoparticles in medicine usually accumulate in one organ of the body or another except the brain(due to the blood-brain barrier). Even if the particles are encapsulated in a biocompatible polymer such as PEG, the only parameter affected is the blood stability time of the nanoparticles.

The most common organ of deposition is the liver and spleen, although the heart and lung tissue are major contenders also. Particles if size range 500-1000 nm tend to accumulate in the lungs and kidneys and the specific reaction to such particles depends on the metal composition and the encapsulating polymer. 

Particles of lower size range(10-200 nm) accumulate preferentially in the liver and spleen. Even if the accumulated particles are benign, saturation causes necrosis of tissue. I recently read about distribution of gold nanorods in mice. Saturation of nanorods in the liver caused necrosis of liver tissue after dosage of 0.3 micrograms over a period of four weeks.

While particles of higher size range are evacuated after a week of ingestion, the smaller particles are permanently trapped in the body tissue.

Reference: https://www.quora.com/How-are-nanoparticles-used-in-nanomedicine-removed-from-the-body

Which nanomaterial is used to prevent the WBC from taking gold nanoparticles as an antigen?

Gold nanoparticles are typically smaller than several hundred nanometers in size, comparable to large biological molecules such as enzymes, receptors, and antibodies. With the size of about one hundred to ten thousand times smaller than human cells, these nanoparticles can offer unprecedented interactions with biomolecules both on the surface of and inside the cells. Therefore silver nanoparticles can be used as they are antimicrobial in function thereby the white blood cells are prevented from taking au nanoparticles as an antigen.

Reference:https://www.quora.com/Which-nanomaterial-is-used-to-prevent-the-WBC-from-taking-gold-nanoparticles-as-an-antigen

Why are metal nanoparticles used more than polymer nanoparticles in biological (green) nanoparticles?

There are lots of reason for choosing metal over polymer nanoparticles. some of them are:-

1. Shape and size of metal nanoparticles can be easily controlled and synthesized
2. Some metal being inherently magnetic in nature can be used for targeted and controlled drug delivery application
3. Most of the metal intrinsically photoactive can be used in for photoactivated degradation of some specific cell which is not possible in a pure polymer
4. polymer has a large molecular weight and controlling for an application is difficult when compared to metal NPs.

Reference: https://www.quora.com/Why-are-metal-nanoparticles-used-more-than-polymer-nanoparticles-in-biological-green-nanoparticles