Carbon nanotubes are allotropes of carbon with numerous outstanding properties. In simple words, they are the strongest and stiffest materials known, and thus have many potential applications in various technology/science fields. As for their ideal structure, they can be thought of as hexagonal networks of carbon atoms, rolled up to form seamless cylinders. The bond between the carbon atoms is covalent sp2, which is the reason why they are so strong and stiff. Other than strength, carbon nanotubes have electrical, thermal and many more useful properties. These numerous characteristics make them very desirable in many fields — nanotechnology, electronics, optics, architecture and the medical field.
Combining carbon nanotubes with biological systems can significantly improve medical science — especially diagnostics and disease treatment. Nothing has been fully developed and finalized yet, but we see progress every day.
As an example, we’ll take anti-cancer treatment. When a patient goes through regular chemotherapy, he loses hair and has some other side effects for one reason — because chemotherapy doesn’t destroy “bad” cells only. Along with those tumor cells, it destroys healthy cells too. That’s why scientists are working so hard to avoid that. And carbon nanotubes could make that possible. Scientists from Stanford University have discovered that nanotubes, when exposed to infrared light, tend to heat up to 160°F (70°C) in just 120 seconds. If they are placed inside the cancer cells, they simply destroy them. Testings also showed that infrared has no effects on cell where no nanotubes are placed. This could lead to development of a cancer-killer.
Gene therapy could also be improved by using carbon nanotubes. Let’s say that a damaged or missing gene could be replaced with another one from outside. But that’s complicated — because DNA can’t pass through the cell membrane. What is needed is a transporter, and modified carbon nanotubes play their role here.
Another application of carbon nanotubes in medicine is for sensing the molecules or species. Many studies on the electrochemical reactivity of carbon nanotubes showed that carbon nanotubes can enhance the biomolecules and promote the electron transfer in proteins. It has been found that carbon nanotubes promote electron transfer in heme containing proteins. In heme containing proteins carbon nanotubes are able to access the heme centre of biomolecules that is generally not sensed by the glass electrodes.
Carbon nanotubes can also be used as blood vessels in order to deliver drugs to their target. When the drug delivery is done that way, the drug dosage can be lowered (and it’s cheaper for the pharmaceutical companies). There are two methods, both equally effective — a) the drug can be attached to the side or behind, b) or the drug can actually be placed inside the nanotube.
Carbon nanotubes have many potential applications, but lack of technology for mass production and the costs of the production is what is holding them back. However, considering all the progress they could bring to various fields — especially medicine, we can say that their time is yet to come.