Scientists are developing nano-submarines for drug delivery

Treating diseases on cellular level is extremely difficult because of the microscopic scale. It is especially true for cancer, which is why contemporary therapies are affecting a lot of the surrounding tissue. However, chemical and biomedical engineers from the UNSW Sydney proved that it is possible to design effective miniscule self-propelled submarines that could deliver medicine directly to affected organs.

Scientists have tried developing microscopic nanorobots before, but they all relied on external manipulation to get to the target site. This new technology allows creating particles that navigate themselves by taking advantage of variations in biological environments – they respond to changes in biological pH environments to self-adjust their buoyancy. This is what makes them similar to submarines – they have ballast gas (gas bubbles kept in the motors of these nanorobots) that can be retained or released according to surrounding pH levels. This should allow these particles to flow directly to the target site.

This is quite a significant achievement. Current nanomotors can adjust themselves in a 2-dimensional manner (left or right) and usually require external manipulation such as light, electro-impulses or magnetic fields. This new approach would allow nanorobots to adjust their buoyancy and move in a 3-dimensional space. Scientists say that this could result in a revolutionary way to deliver drugs. For example, cancer medicine for gastrointestinal tract could be taken orally and would release nanorobots once it reaches the gastrointestinal fluid. Robots would travel up or down, depending on where the target site is. Then they would be absorbed by the cells and would start doing their job.

But what are those nanorobots? Scientists say that these tiny submarines are actually composite metal-organic frameworks (MOF)-based micro-motor systems containing a bioactive enzyme (catalase, CAT) as the engine for gas bubble generation. Although scientists are mostly talking about cancer treatment, the same technology could be applied in other areas, where nanorobts could be useful. This is why now scientists are planning to prove the versatility of this technique in other types of nanoparticles. The ultimate goal is creating a technology, which would allow delivering drugs very precisely and efficiently.

Someday this could revolutionize cancer treatment. Nanorobots could be released into the body and travel independently to the target site. Here they could be absorbed by the cells and could initiate their activity. This would allow for a safer and more precise treatment, which would not damage the surrounding tissue so much.

Source: UNSW