Microscopic swimming devices could deliver drugs to targeted places in the human body

A new method of guiding microscopic swimming devices could be used to deliver medication to a targeted location inside the body, according to new research.

The study by engineers at the University of Sheffield reveals that tiny spherical bead-like devices can be guided by physical structures while swimming inside fluids.

This opens up a wealth of future possibilities, such as using structures in the body to guide drug delivery, or cracks in rocks to direct environmental clean-up and exploration, according to the researchers.

Dr Stephen Ebbens, Department of Chemical and Biological Engineering at Sheffield, said: “When you’re dealing with objects on such a small scale, we found that although our method of moving the devices using a coating and chemical reaction worked very effectively, it was difficult to control its direction, due to other molecules in the fluid jostling it.

“We’ve been working on ways to overcome this and control the movement of the devices along a path using physical structures to direct them.

“We are now working on applications for using these devices in the body, in the shorter term focusing on using them for medical diagnosis.”

The devices are a similar size to cells and bacteria, around a hundredth of the average diameter of a strand of human hair.

They are given a catalytic coating on one side, which creates a chemical reaction when fuel molecules are added, causing the device to move automatically on a pre-determined route, using natural structures as a guide.

Researchers say they could be used to find proteins indicating cardiac problems or to look for circulating tumour cells that can indicate the spread of cancer.

In addition to medical applications, these devices could be used in other fields, such as to locate indicators of contamination in environmental samples or to deliver neutralising chemicals to areas affected by oil spills, by using crevices in rocks as the structural guide.

The research which was published in Nature Communications was a collaborative project led by Dr Stephen Ebbens with Dr Jon Howse and Dr Andrew Campbell from the University of Sheffield; Professor Ramin Golestanian, University of Oxford; Professor Ayusman Sen, Professor Darrell Velegol, Sambeeta Das and Astha Garg, Penn State University. The UK research team were funded by the EPSRC.