A simple dictionary definition of nanomedicine would be “the medical use of nanotechnology”. This sounds fairly simple, but it hardly scratches the surface of nanomedicine, and is an understatement of the potential that nanomedicine holds. Nanomedicine can treat microbial, viral, and fungal diseases, and most importantly cancer.
Nanotechnology is useful in the treatment of cancer cases; as their nanoscale dimensions and large surface-area-to-volume ratios allow them to influence their payloads (the part that kills cancerous cells). The 1-100 nanometre size (1nm = 0.000000001m) allows the drug-containing nanomedicine to be carried directly to cancer cells, not damaging any healthy tissues, whereas traditional forms of cancer treatment may destroy healthy cells during the treatment procedure. Nanomedicine affects only cancerous cells, so has potentially fewer side effects than conventional chemotherapy. A chemotherapy patient would typically experience hair loss, nausea and more. While the use of nanoparticles as drug carriers may reduce the drug’s toxicity, it is difficult to distinguish between the toxicity of the nanoparticle and the toxicity of the drug being carried, making evaluation of the effects on the patient difficult. In essence, there are many benefits to using nanomedicine but there are also many possible drawbacks.
While nanomedicine can be traced back to the use of colloidal gold in ancient times, Metchnikoff and Ehrlich are the modern pioneers of nanomedicine for their work on phagocytosis. Nanotechnology was a term coined by Richard Feynman, an American theoretical physicist involved in the development of the American atomic bomb. His famous talk in 1959, “There’s plenty of room at the bottom” opened the eyes of many other curious scientists across the world. In his talk, he hinted at the idea of nanomedicine, speaking about “small machines permanently incorporated in the body to assist some inadequately functioning organ”. Now, just over 50 years later, this is happening in the medical world. Currently, there are more than 1600 uses for nanotechnology in the world including self-cleaning glass and sunscreen, but there are a specific few that are prevalent when it comes to nanomedicine. These include the creation of vaccines, treating tumours and cancers, medication delivery and wearable equipment.
As stated earlier, despite nanomedicine having many advantages, it also has its share of problems. The most obvious of them all is that as nanomedicine is a fairly new form of treatment, the long-term potential disadvantages are unknown. This may seem an irrational fear, but history shows many cases where something similar has taken place. From the 1930s to the late 1940s, doctors were prescribing cigarettes for patients who had complained of having infections that could be due to dust or germs entering the body. It was only in the 1950s that scientists drew the conclusion that there was a direct correlation between cigarettes consumed by smokers and patients with blackened lungs and hence stopped promoting their use. The first form of nanomedicine treatment that received clinical approval was the drug Doxil, in 1995; only just over 25 years ago. There are also unfortunate environmental impacts: the production of nanomedicine leads to air pollution and environmental toxicity (as well as organ damage for those who are nearby during the production process and aren’t equipped with the correct protection). The last disadvantage I want to mention is perhaps the most counterintuitive one. If the nanoparticles have poor solubility, after entering the body, they can cause cancer – somewhat ironically considering this is one of the main diseases they are meant to cure.
Now, let’s explore what the potential future of nanomedicine in the medical world holds. In the current moment, as discussed earlier, the most predominant use currently is in the field of cancer treatment, however, this is only the tip of the iceberg when it comes to the prospects of nanomedicine. With such rapid advancements in technology, nanotechnology in the medicinal world will also advance rapidly in the future. Proposed ideas lie around drug administration being more precise with the help of nanometres and nanotubes. This technology should be able to target specific cells in a patient who is suffering from life-threatening conditions or even be used in the manufacture of more effective PPE. Nanotechnology could be used in diagnostic nanosensors – these will constantly travel through the bloodstream, allowing for early detection of diseases by identifying specific biomarkers. There could also be theranostics, which are similar to diagnostic nanosensors except that they also work to treat as well as identify illness. Analogously to increased tensions over the environment and air quality, we will soon be able to insert biosensors into our bloodstreams and monitor for any entry of pollutants or toxins.
As we reflect on the history of nanomedicine, how it is currently being used and its future, it is clear that nanomedicine holds great promise as scientists across the world continue to pave the way for nanotechnology in the field of nanomedicine. Regardless of the countless positive aspects of nanomedicine, there are still certain downsides which hold it back from being the ultimate form of treatment.