New liquid-metal for cancer treatment

Researchers in the US are working on, developing  a biodegradable liquid metal which can be used as a drug delivery technique to target and kill cancer cells.

Zhen Gu, a biomedical engineer in a joint program at North Carolina’s State University and University at Chapel Hill said that, “The advance here is that we have a drug-delivery technique that may enhance the effectiveness of the drugs being delivered, can help doctors locate tumors, can be produced in bulk, and appears to be wholly biodegradable with very low toxicity and one of the advantages of this technique is that these liquid metal drug carriers – or ‘nano-terminators’ – are very easy to make.”

In order to develop the nano-terminators, the researchers inject liquid metal (a gallium indium alloy) into a solution with molecules known as polymeric ligands. By using the ultrasound waves, the liquid metal bursts into nanoscale droplets which measure about 100 nanometres in diameter. The ligands then attach to the surface of the droplets and form a skin like cover that prevents the alloy from merging back together.

When the anti-cancer drug which is known as doxorubicin is introduced to this solution, the ligands on the nanodroplet soak it up, thus creating drug-laden vessels which can be separated from the solution and introduced into the patient’s bloodstream.

An additional type of ligand that attaches to the nanodroplets can effectively search and target cancer cells, by making receptors on the surface of the cells latch onto and absorb the nanodroplets – which ends up releasing the doxorubicin inside the cancer cell.

When it gets inside the cancer cell, the liquid metal then reacts with the cell’s acidity and releases gallium ions, which actually boosts the performance of the doxorubicin while degrading the metal.

“Based on in vitro tests, we believe the liquid metal degrades completely in a matter of days into a form that the body can successfully absorb or filter out, without notable toxic effects,” said one of the team, Yue Lu.

The findings, published in Nature Communications, by the researchers, detail how the nano-terminators in the liquid metal were more effective than doxorubicin alone at inhibiting the growth of ovarian cancer cells in testing on a small mouse model. The team plans to continue their research, first with a larger animal study, before hopefully moving on to clinical trials with people.

Gu said that, “This was a proof-of-concept study, but very encouraging, Like the fictional Terminator, this carrier is transformable: smashed from bulk material, fused inside cancer cells and eventually degraded and cleared.”