Nano-reactor created to produce hydrogen biofuel

A virus has been modified to split water into its two elements by a team of US scientists.

Due to the protection provided by the capsid the ‘nano-reactor’ is 150 times more effective than the enzyme, nitrogen-iron (NIFe) - hydrogenase, catalysing alone.

Trevor Douglas, from Indiana University, said: “Essentially, we've taken a virus's ability to self-assemble myriad genetic building blocks and incorporated a very fragile and sensitive enzyme with the remarkable property of taking in protons and spitting out hydrogen gas.

“The end result is a virus-like particle that behaves the same as a highly sophisticated material that catalyses the production of hydrogen."

Hydrogenase is created from two genes from E. coli, hyaA and hyaB. The capsid was taken from bacteriophage P22. P22-Hyd, the name of the nano-reactor – is produced through a simple fermentation process at room temperature. The reaction is reversible meaning the enzyme can be used either as a hydrogen production catalyst or as a fuel cell catalyst.

Professor Douglas said: “This material is comparable to platinum, except it's truly renewable. You don't need to mine it; you can create it at room temperature on a massive scale using fermentation technology and it is biodegradable. It's a very green process to make a very high-end sustainable material.”

NIFe-hydrogenase was selected by researchers as it could ‘easily integrate’ into biomaterials and tolerate exposure to oxygen. It also retains the ability to catalyse at room temperature and have a higher chemical resistance – both do not hold true for unmodified NiFe-hydrogenase.

The next step is to find ways to achieve a catalytic reaction in P22-Hyd from solar power rather than inside a laboratory, with the aim of incorporating it into solar panels.

The research was published in Nature Chemistry.