PhD student Mostafa Seifan, left, and researcher Dr Aydin Berenjian, from the University of Waikato, developed a self-healing concrete.

It's like the stuff you see in sci-fi movies.

But a concrete that regenerates and heals itself, made using nanobiotechnology, was developed right here in New Zealand.

The breakthrough research was championed by Dr Aydin Berenjian​ and PhD student Mostafa Seifan​ at the University of Waikato.

SUPPLIED The crack healed itself in 28 days.

And not only are they the first in New Zealand to use this technology in this way, they're the first in the world.

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Every year, billions of tonnes of concrete are created worldwide, but all of it is vulnerable to damage, including cracks.

Berenjian and Seifan spent four years researching the problem and came up with a solution that involved fermentation.

"The process is called solid-state fermentation - when the water level is below 10 per cent - similar to what we have in sourdough or many other food products," Berenjian said.

"Many products we look at produce acids or alcohol - but here, we look at biomineralisation, the production of calicium-carbonate, like mineral salts."

The pair immobilised the bacteria inside iron nanoparticles to help the bacteria become more active and to increase tolerance of harsh environments - like concrete - which make it difficult for microbes to grow.

Anything that makes it difficult to survive, the bacteria nanoparticles can tolerate, Berenjian said.

"So take bread for example - it's a semi-solid environment, there's very low water activity, and when you get the bread on the bench for a couple of days, you will start to see mould growing.

"Those moulds are in the bread environment and they get exposed to humidity. They have the nutrients in the bread and when they feel the conditions are good, they start to grow.

"So say the same thing is happening in the concrete environment. So we put the microbes there, but there are a couple of issues - we don't have nutrients.

"But these microbes have the capability to use nutrients from the environment, so they use carbon dioxide as a source of nutrient and we have a little bit of humidity in the environment as well.

"When the cracks starts, they start to produce the product, which here is calcium carbonate. It's a very biocompactible product with many structures, not just concrete. So they start to produce calcium carbonate as part of their metabolic pathway, which heals the crack."

In one experiment, a crack in the concrete took 28 days to self-repair.

And it's not only a protocol that can be used for concrete - there are several other possibilities.

Berenjian said it can be applied to oil reservoirs to help with cracking and to stabilise soil and absorb pollution.

The next step, however, is to reduce the cost of production, as at the moment it costs about $200 a cubic metre.

"We have had a lot of interest and our work has been thoroughly reviewed and published. It has huge potential for a range of other materials, industries and uses worldwide."