What is”Nano” ?
When we talk about nano-particles we mean those particles which have dimensions that are measured in nanometres.A nanometre (symbol nm) is one billionth of a metre and so equal to 10^-9 metres; it is the typical atomic scale (for example the DNA double-helix has the diameter of 2nm).
What is Nanotechnology?
Nanotechnology is the science that works in the world of nanometres (usually with objects sized between 1 and 100 nm), so the branch of science and technology capable of operating with and manipulating single atoms or molecules. It developed in the 1980s and today we hear more and more frequently people talking about it. In a certain sense we have always coexisted with it, but now for the first time we know what it is and we are able to interact with it.
As with every branch of science, we don’t know much about nanotechnology and have just started to explore this world in depth. And as I said in the introduction, something that we don’t know well usually scares us.
Along with the extraordinary perspectives that this world is opening to us, doubts and fears, especially for health, are rising up.
And so the title of this post: can we consider nanotechnology totally safe? Are there risks for our health?
Data are to this day insufficient to answer this question correctly and to prompt laws to regulate research (of course, a company producing toothbrushes containing nanosilver particles will tell you that you don’t need to worry about it!).
Nanotech involves almost all the fields of science and its applications are countless. Some examples are branches like nanomedicine (nanovectors, cure against cancer), nanomaterials (carbon nanotubes, space lifts and hydrophobic sponges), nanoelectronics (nanotransistors and humanoid systems), nanoenergetics (nanodots solar cells), nanocosmetics (sun tanning creams and toothpaste), nanofood
(chocolate and nanoplatinum supplements).
I’d like to present you briefly some projects involving nano particles and products that we should already know very well.
The most important chemical elements in the field of nanotech are carbon, silver, gold, zinc, silicon, titanium, of course in their nano-status. Concerning this I think it’s fundamental to explain that there are enormous differences between an element in its common form and in its nano form: I’m not able to make a physical demonstration, but as far as the world of particles is concerned, the laws of Physics that are valid for the macroscopic world, don’t work at all with the nanoworld; in other words, we can’t foretell the behaviour of nanoparticles because it isn’t … common (maybe I should deal with this topic in depth in a specific post, I think there are a lot of interesting things to say about..).
Let’s start with something very simple: a common sponge, whose chemical structure has been modified by nanotechniques, becomes hydrophobic and so oleophilous. Imagine then a tiny sponge able to absorb the cholesterol present in blood, or better an enormous sponge that can absorb entire blotches of petrol in the sea and avoid environmental disasters!
Nanomedicine has reached limits that until less than ten years ago were unthinkable of. Nanovectors are sorts of nanorobots that reach the specific area of an organism that needs to be cured and are able to release the right amount of medicine. Tumoral cells are covered with magnetic nanoparticles and exposed to magnetic fields, and in this way the healthy cells around a cancer are preserved.
The industrial and energetic applications of nanotech are really interesting. Exploiting the enormous (to this day) reserves of silicon, scientists have created solar cells with silicon nano particles. These cells are incredibly small if compared with the existing solar panels and so an incredible reduction in costs, dimensions and exploitation of the environment would be possible. And imagine if car bodies would be entirely made of this material……. no more petrol, no more pollution, no more global warming!
Talking about carbon, scientists have exploited its properties, which in a particular chemical structure called “carbon nanotube” allows to create materials which are more resistant than diamond. The possibility to build the structure of a “space elevator” using carbon nanotubes is still object of studies.
Another example is the application of nanotechnology in building construction to create water-repellent varnishes, taking inspiration from the surface of the lotus leaf observed at nanometric level.
I would also like to give some examples of a possible “negative” use of the potential advantages that nanotechnology offers. Most of the cases I know about concern unfortunately cosmetics and the food sector.
Let’s start with sun tanning creams containing zinc nano particles, because in its nanostatus this element is invisible on the skin. But researches don’t assure what kind of effects these particles can have on cells and organs after having been adsorbed!
Toothpaste have been produced for about five years now with nano-silver and nano crystals of apatite, a mineral contained in our bones, to exploit the antibiotic properties of nanosilver (as well as nanogold) and the capacity of apatite to repair tooth surface (biomineralisation).
And what about nano-titanium in chocolate and sweets to avoid the formation of white coat on them?
Furthermore, first supplements containing nanoplatinum and others nanoparticles are appearing!! It’s incredible to think that someone, to make a profit, is trying to convince people to drink…. PLATINUM!!! These supplements are mostly used in the bodybuilding sector using the following advertising slogan “these powerful nanoparticles violently invade your cells, causing an uncontrollable increase in muscle resistance!”
“make it like mother nature has always made“
This is the principle that inspires (or better should inspire) researchers in their work. As I said before, we have always coexisted with forms of nanotechnology. Think of lotus leaves, of diatom shells that have made use of biomineralisation for millions of years. Or think of the gecko, and any other animals able to walk on walls, that uses nanometric hairs, exploiting Van deer Vaals forces as a glue.
My final question is, don’t you think there is, or should be, a way to “make it like mother nature has always made“, obtaining the double effect of maximizing benefits and minimizing risks? To cut costs but also the exploitation and destruction of our planet?
Research goes on, let’s see what happens.