Nanobots, tiny nano-sized robots and vehicles that can navigate through blood vessels to reach the site of a disease could be used to deliver drugs to tumours that are otherwise difficult to treat.

Once injected or swallowed, most drugs rely upon the movement of body fluids to find their way around the body. It means that some types of disease can be difficult to treat effectively in this way.

One aggressive type of brain tumour known as glioblastoma, for example, kills hundreds of thousands of people a year. But because it produces finger-like projections into a patient’s brain tissue that damage the blood vessels around them, it is hard for drugs to reach the tumour site.