The term nanotechnology, according to the description given by the National Nanotechnology Initiative (NNI), means the manipulation and use of matter that has at least one size comparable to the atomic one, that is of the order of nanometers (10-9 meters). This definition suggests that classical physics, which dictates the rules for the macroscopic world, is no longer sufficient for a complete description of physical phenomena that occur on such a small scale, in fact the microscopic effects are no longer negligible and we move into the realm of quantum mechanics.
The applications of nanotechnology are varied and include the most diverse fields of science, from semiconductor physics to surface science, including medicine. Nanomedicine refers to the combination of molecular diagnostics, a set of techniques used for the analysis of biological markers, with nanotechnology, so that the ability to detect specific cells or tissues can be improved, greatly increasing precision and accuracy.
Thanks to the use of nanoparticles, being 100 to 10,000 times smaller than the human cell, it would be possible to operate on the same level on which a good part of biological processes take place, including those that cause cancer. Today the disease can be recognized, in most cases, only when it reaches a considerable size, but it is known that it is caused by genetic alterations at the DNA level.
In the therapeutic field, the use of nanotechnology can offer really important contributions. In fact, unlike classical therapies, it is not limited to a single therapeutic pathway, but has many possible uses, including nano-radiotherapy, gene therapy and cancer diagnostics. Precisely for the latter, special contrast agents made of nanoparticles have already been developed. Thanks to their characteristics and to the help of special platforms and technologies, they can identify the tumor with an unprecedented precision. For example, researchers at Stanford University and Memorial Sloan Kettering Cancer Center in the United States have developed nanoparticles capable of outlining the margins of brain tumors before and during surgery, offering the surgeon a privileged point of view and enabling him to recognize (and eliminate) even individual tumor cells.
Thanks to their extremely small size, nanoparticles can cross the vessel wall and reach the tumor directly, accumulating inside the cancerous mass. Even the blood-brain barrier, an obstacle to the passage of many drugs, can be crossed by some nanoparticles able to reach the central nervous system. Last but not least, new technologies have allowed to build real "nanovehicles" through which it is possible to improve the stability of some molecules and make them reach the target organ. In some cases, these therapeutic nanoparticles recognize the tumor cell and destroy it only after being activated from the outside, perhaps with light or, as in the research mentioned at the beginning, with microwaves.
Although most of the therapies have already been approved and are applied daily in clinics, the diagnostic and therapeutic approach through nanotechnology for the treatment of cancer is still largely under development. In fact, to date there is not enough knowledge about the risks that these technologies can bring, for example, some atypical behavior of nanoparticles may give rise to side effects on biological organisms. In addition, nanoparticles are so small that the body, under certain circumstances, can eliminate them so quickly that their action, as a drug or diagnostic tool, is completely useless. Finally, it is also possible that large quantities of nanoparticles accumulate in the organs giving rise to toxicity phenomena.
So, even if to date the studies are still in the experimental phase, the entire scientific community turns more and more attention and interest in this field, which could really revolutionize our world and save countless lives.
Written by Marco Succodato of the VGen Engineering Hub
