In a recent study, researchers have revealed that they want to use sperm cells to help deliver cancer treatment to patients. A team from the Leibniz Institute for Solid State and Material Research in Dresden, Germany have successfully used bull sperm to deliver chemotherapy (in bulls, not humans).

According to the team, when sperm was soaked with a particular drug, it could reduce the amount of cancer cells by 90% in just three days.

Engadget reported that the biggest benefit of using sperm, which is naturally mobile, is that it does not cause immune responses from cells such as bacteria. This eventually allows the chemotherapy to have an impact without killing healthy cells.

Researchers said that the sperm cells were fitted with iron "hats" to help control the medicine through magnetism. The sperm cells were able to break through the walls of the tumor and attack the cells directly, instead of bathing the tumor in chemotherapy.

This latest study comes just a few days after it was reported that tiny springs controlled by magnets could one day be used to fight cancer.

Scientists from the Chinese University of Hong Kong, led by Professor Li Zhang, are using a biodegradable substance called spirulina algae. The nanobots, which are covered in an iron coating, are controlled by magnetic fields. Experts said that the coil shape of the nanobot allows it to move easily with the help of magnetic waves.

"Rather than fabricate a functional microbot from scratch using intricate laboratory techniques and process, we set out to directly engineer smart materials in nature, which are endowed with favourable functionalities for medical applications owing to their intrinsic chemical composition," Zhang said.

He added: "For instance, because these biohybrid bots have a naturally fluorescent biological interior and magnetic iron-oxide exterior, we can track and actuate a swarm of those agents inside the body quite easily using fluorescence imaging and magnetic resonance imaging."

The nanobots are allowed to biodegrade naturally over hours or days (depending on the thickness of the iron coating). Thus, when cancer cells are exposed to the nanobots, only about 10% (of the cancer cells) manage to survive. Researchers say that it is harmless to other cells in the body that eventually makes it a viable solution for fighting cancer.