Nanotechnology is the science of very small structures called nanomaterials and nanoparticles and the techniques of their production and research. The size of nanoparticles can be compared to thousandths of the thickness of a human hair. And, most interestingly, the reduction in scale is accompanied by unusual properties that are not found in macroscopic versions of the materials we make our nanomaterials from.
Nanotechnology is a fairly new field of science, brought to life by the famous physicist Richard Feynman in his famous lecture "There's plenty of room at the bottom", delivered in 1959 at the California Institute of Technology.
In recent years, the term "nanotechnology" has become a key word to guarantee that products "with nanotechnology" are state-of-the-art, high-quality products based on the latest scientific findings. The slogan "with nanotechnology" excites the minds of both consumers and marketing departments. However, it is worth knowing that nanotechnology is not just socks or glass liquids with nanosilver, widely advertised in the media (moreover, nanosilver itself has been known for over 100 years). This science can offer us much, much more, especially in such important fields as, among others, medicine and especially oncology.
The desire to save lives and make them more comfortable means that we spare no expense on medical research. By 2030, we expect that, of the various branches of nanotechnology, nanomedicine will have attracted the most funding. So let us look at how this relatively young science can change our lives and health for the better.
Personalised medicine
The use of nanoparticles as active substances carriers, such as cancer drugs, allows us to obtain a drug form that can selectively accumulate in disease-affected areas, such as tumour foci. This gives us a chance to reduce the undesirable side effects that therapy causes in the body. One of the first commercially available medications was Doxil, i.e. doxorubicin (a frequently used chemotherapeutic agent) encapsulated in biocompatible follicles called liposomes, known, among others, from cosmetics. Their structure, inspired by the natural cell membrane, makes them the most frequently used nanoparticles in preparations, which have successfully moved from the stage of scientific research to availability to patients - of 25 preparations available on the market based on nanotechnological achievements , as many as 10 are precisely based on liposomes.
Passive and active targeting
Controlled delivery can be achieved in accordance with two main concepts - passive and active targeting. Passive targeting takes advantage of the properties of tumour tissues resulting from their rapid growth - the rapidly forming structures, including blood vessels, have a slightly "looser" organisation, which allows particles smaller than 100-200nm to penetrate and accumulate more easily. This mechanism, described in 1986, was called EPR (Enhanced permeability and retention) and is the basis for the application of the already mentioned Doxil, which causes less severe side effects than doxorubicin in its traditional form.
Active targeting is a slightly more sophisticated technique and is based on the fact that disease-affected cells have a different array of specific proteins on their surface than healthy cells. These proteins can be likened to locks into which the appropriate keys will fit - specific molecules that can be deposited on the surface of the nanoparticle using various methods. By 'addressing' them in this way, the drug delivery carried by the particle will go primarily to affected cells, allowing more of the drug to be directed at the cancerous focus and thus reducing the overall side effects of treatment. This array of specific proteins on affected cells can vary between patients - so if we identify the right 'lock' in our patient's affected tissue, we can select the right key to increase the chances of successfully treating their particular case.
Combining diagnosis and therapy - theranostics
Theranostics is a special approach in personalised medicine, combining diagnostics and therapy - hence the origin of the name. Using one preparation, we are able to simultaneously diagnose (e.g. locate cancerous foci in the body or assess the stage of the disease) and treat. One of the best-known examples of theranostic activity is the use of iodine radioisotopes in the diagnosis and treatment of thyroid cancer. However, thanks to nanotechnology, we are able to take theranostics to the further level of sophistication. We have learned to build medical nanoparticles from components with different functions like LEGO bricks. In a single nanocarrier subunits detectable with known diagnostic methods such as magnetic resonance imaging or computed tomography can be combined; at the same time, we can combine the carrier with a drug or even an appropriate molecular anchor that will lead the whole structure to our tumour focus. And although the implementation of such a task is not a trivial matter, the fact that we have such a possibility is a significant achievement and numerous teams of scientists around the world do not spare time and resources for the development of theranostic systems.
Summary
Nanotechnology can offer us much more than we can see on shop shelves today. Progress in this field is driven by the unlimited imagination of scientists and the ever-evolving methods of making and testing nanomaterials. The US National Cancer Institute predicts that the coming years will bring us significant advances in the early detection, diagnosis and targeted cancer therapy- owing to the discoveries and applications of nanotechnology.
