Progress in medicine has been realized through revolutions. The x-ray, antibiotics, monoclonal antibodies and, more recently, immunotherapy, deep learning, and robotics are all examples that have dramatically shaped medicine and provided better ways for clinicians to diagnose and treat diseases. For instance, in robot-assisted laparoscopy, the da Vinci Surgical System, introduced in the early 21^st century, has become a major tool in head and neck surgery. The use of other robots in medicine has risen tremendously over the past several years, and the field is continuously developing and branching into more areas.

The transition from macroscopic robots to nanorobots is among the next revolutions in medicine. It will soon be possible for them to perform surgical interventions, at the molecular level, in regions of the body that are otherwise inaccessible to surgeons. Alternatively, they will be able to reach and target distant pathologies for advanced diagnosis. We also envision them shuttling medications directly into a localized tumor. Altogether, performing tasks on the nanoscale will pave the way for many interesting applications.

Nanorobots will have to overcome several hurdles to operate on the nanoscale. To apply a mechanical force, they need energy. Contrary to our expectations, nanorobots, because they are miniscule (1 nm), can not store energy for their work. Thus, energy must be supplied externally. This can be achieved through electromagnetism, chemical reactions, or light. The resulting energy should be sufficient to operate the mechanical motor of the nanorobot to perform its mechanical task promptly and efficiently.

Another, hurdle that must be overcome is the human body’s defense. As external elements, nanorobots might induce an immune response and become toxic. Thus, the nanorobots must be non-toxic (at least at the concentration that is required for their operation).

Lastly, nanorobots should be programmed to target a specific distant pathology to ensure that they do not operate on healthy cells (or, in the case of a diagnosis, do not reach non-pathological tissues).