Nanotechnology and Nanomedicine — Welcome To The Future
Nanotechnology and Nanomedicine — Welcome To The Future
Nanomedicine is a branch of medicine that applies the knowledge and tools of nanotechnology to the prevention and treatment of diseases. And what is nanotechnology? When we say something is “nano” we mean very small. Very very small. The size of a nanometer is one-billionth of a meter, which is about 100,000 times smaller than the width of a human hair. Making new things at this incredibly small scale is called nanotechnology, and it is one of the most exciting and fast-moving areas of science today.1
Some nanomaterials are naturally occurring. You can find them everywhere: in volcano ash, ocean spray, fine sand, and dust. Naturally occurring nanostructures are also present in plants and animals. For example, nanostructures in insects’ eyes ensure an anti-reflection and water-repelling effect so that they can fly safely.
Nowadays, scientists can create nanostructures themselves. By rearranging the atoms of an object, they can make new nanomaterials with new properties (for example, stronger, lighter, or different in color). Properties also change in relation to their size, and this is the magic of the technology.
Nanotechnology in the Food Industry
In the food industry, researchers are working with nanotechnologies to create new products that may benefit health and diet. For instance, nanosilver has antibacterial properties that can be useful in food contact material such as cutting boards. In food supplements, nanosized carriers increase the absorption of nutrients. Nanosensors can be incorporated into the packaging to monitor food quality and shelf life from manufacturers to consumers. Nanomaterials can also make the food tastier or healthier. Carving up a grain of salt into nanosized grains increases its surface area significantly, and this means that your food needs far less salt to be equally tasty. Of course, the health authorities need to be sure that food nanotechnologies do not cause any harm to consumers, which is why nanoengineered food requires strict safety assessments.2
Nanotechnology for Drug Delivery
Scientists are able to put drugs in spheres that are small enough that you could put about 1000 of them side by side into a cross section of your hair. The fact that we can now see and work with these tiny particles means a lot for the future of medicine. These spheres are called nanoparticles (NPs), and they can be administered systemically and circulate in the body to deliver a drug. This is actually nothing new. A drug delivery system like this, called Doxo, was first approved in 1994 as a liposomal formulation of a drug called Doxorubicin.
However, the 2.0 version of these drug delivery systems has homing molecules that allow a much more targeted delivery. They go inside the body, circulate under the radar of the immune system, find diseased tissues, and release the drug inside diseased cells. It is a “search and destroy” mechanism. Think about it as a commando of nanorobots (or nanobots) going around the body to find what needs to be destroyed. A targeted system like this drastically reduces the side effects of drugs. More than 99% of a drug usually ends up where it is not needed. Targeted nanoparticles can instead deliver a much higher payload to the diseased site.
Nanobots can be easily regarded as nanomedicine’s most important breakthrough. Around the world, researchers are developing specialized nanobots to perform a wide variety of surgeries using an external magnetic field to direct the bots. For example, nanobots can be used for tissue biopsies: Structures resembling unfolded cubes made from elastic polymers can grab tissue samples by folding up and holding them inside the cube. Another useful application of nanobots is to clear blocked arteries: Corkscrew-shaped chains of iron oxide beads are injected into the bloodstream, and they drill through arterial blockages, breaking up atherosclerotic plaques.
However, the application where nanobots, specifically DNA origami nanostructures, are most promising is cancer treatment. In 2006, it was first demonstrated that a single protein could be incorporated into a DNA tetrahedron, opening up a plethora of potential applications in drug delivery.3,4
DNA nanostructures have the great advantage of being biocompatible and biodegradable. They possess abilities to enhance efficacy of chemotherapy, reduce adverse side effects, and even circumvent drug resistance. Several studies have reported that DNA origami nanostructures of various sizes and shapes showed no significant cytotoxicity either in vitro or in vivo. These so-called DNA origami nanobots flow in the bloodstream and are equipped to recognize cancer cells proteins. When they find the cancer cells, they can, for example, release a blood-clotting enzyme inside the tumor. Within a few hours, the blood supply to the tumor is cut off, leading to tissue death.
Smart Pills and Smart Bandages
Ingestible capsules containing sensors, cameras, and more are already changing the face of medicine. The FDA approved the first PillCam in 2001, and it has been used in millions of procedures ever since. Drug dose tracking pills contain sensors that relay data through a patch worn by the patient. An app tracks drug dosage over time, and logs can be shared with doctors and healthcare professionals, improving treatment adherence and patient outcome. Smart sensor capsules developed by MIT scientists can lodge in the stomach for about a month, tracking vital signs for diagnosis and treatment monitoring. Preloaded compartments of smart sensor capsules can be customized to release medications, having great utility for those diseases with a strict medication regimen.
Smart bandages are also being studied. These are bioabsorbable bandages made from hydrogels that can be left in place until they dissolve. What’s interesting is that these special bandages can embed nanofibers containing clotting agents or growth hormones to speed up healing or a sensor to detect infections and release antibiotics as needed.5
Nanomedicine and COVID-19
Nanotechnology-based products are also of great interest for the current COVID-19 pandemic. They can be used to prevent transmission by integrating nanomaterials into cleaning products and personal protective equipment through lipid nanocarrier-based mRNA vaccines like the ones developed by Pzifer. Moreover, nanomaterials can also be used to enhance the selectivity and specificity of various techniques used to diagnose COVID-19. Finally, nanomedicines could be used to modulate the immune system to promote immune responses against SARS-CoV-2 infection.6
Challenges for the Future of Nanotechnology and Nanomedicine
As with every novel and revolutionizing technology, nanomedicine comes with its challenges, especially with regards to its widespread clinical application. First of all, more research is needed to find out the long-term implications and impact of nanotechnologies. Some questions that need to be addressed are the environmental impact of nanotech manufacturing, whether nanotech accumulates in living tissues and organs, and whether they can be affordably manufactured at a large scale.
Another aspect regards nanotech regulations. In 2019, the FDA proposed new guidelines for smart pills. These will require pills to be tested as either a drug or a device but not both; some think that this could hinder progress for combination products.
Finally, public support is another key player, as with any developing technology, its public perception has direct implications on future policies and has to be taken into account by academia and industry alike. The good news is that a 2020 study found that the majority of the respondents had a positive or neutral attitude towards nanotechnology and that the attitude towards nanotechnology was not affected by age or education. 7
1. Soares, S., Sousa, J., Pais, A., & Vitorino, C. (2018). Nanomedicine: Principles, properties, and regulatory issues. Frontiers in Chemistry, 6, 360. doi: 10.3389/fchem.2018.00360
2.Sekhon, B. S. (2010). Food nanotechnology — an overview. Nanotechnology Science and Applications, 3, 1–15.
3. Erben, C. M., Goodman, R. P., & Turberfield, A. J. (2006). Single-molecule protein encapsulation in a rigid DNA cage. Angewandte Chemie, 45(44): 7414–7417. https://doi.org/10.1002/anie.200603392
4. Udomprasert, A. & Kangsamaksin, T. (2017). DNA origami applications in cancer therapy. Cancer Science, 108(8): 1535–1543. doi: 10.1111/cas.13290
5. Derakhshandeh, H., Kashaf, S. S., Aghabaglou, F. Ghanavati, I. O., & Tamayol, A. (2018). Smart bandages: The future of wound care. Trends in Biotechnology, 36(12): 1259–1274. https://doi.org/10.1016/j.tibtech.2018.07.007
6. Singh, P., Singh, D., Sa, P., Mohapatra, P., Khuntia, A., & Sahoo, S. K. (2021). Insights from nonotechnology in COVID-19: Prevention, detection, therapy and immunomodulation. Future Medicine 16(14). https://doi.org/10.2217/nnm-2021-0004
7. Joubert, I. A., Geppert, M., Ess, S., Nestelbacher, R., Gadermaier, G., Duschl, A., Bathke, A. C., & Himly, M. (2020). Public perception and knowledge on nanotechnology: A study based on a citizen science approach. NanoImpact, 17. https://doi.org/10.1016/j.impact.2019.100201