Condoms from spinifex? Now that’s a fraction too much friction …

The idea of a super-thin condom made from spinifex – a spiky tussock grass commonly found growing in the desert sands of arid central Australia – sounds a tad uncomfortable at first blush.

But that’s what emerged after a group of nanotechnologists started working with Indigenous groups in north-west Queensland to combine ancient Indigenous knowledge with up-to-the-minute technology.

Now, their innovative efforts are attracting global interest, while also generating jobs for Aboriginal people in harvesting the grass that grows in extremes of temperature, a must-have sustainability tick for the warming climate to come.

About 190 kilometres north-west of Mt Isa near the small border town of Camooweal is a solar-powered harvesting plant and laboratory.

A two-day drive from the nearest capital city or university, the lab has a mass spectrometer, CO₂ extraction plant, ceramic ball-mill, high-pressure homogeniser, 80 staff and, literally, tonnes of spinifex.

Spinifex, or Triodia is an Australian tussock grass known as tjanpi (grass) in central Australia where it has several traditional uses among Aboriginal groups.

Working in partnership with Camooweal traditional owners, scientists from the University of

Queensland’s Australian Institute for Bioengineering and Nanotechnology (AIBN) have developed a method of extracting nanofibres from spinifex.

They are proposing to process the native spinifex grass into commercial applications, including super-strong roads and tyres, and as an additive in latex products such as ultra-thin condoms and surgical gloves.

The Indjalandji-Dhidhanu people are traditional owners of Camooweal and have occupied the lands around the tiny town for an extended period.

Their people are steeped in harvesting practices of the spinifex and signed a collaborative research agreement with AIBN in 2014.

Indjalandji-Dhidhanu man and director of the Dugalunji Aboriginal Corporation, Colin Saltmere, says spinifex is a sacred material to Indigenous people.

“But also a material we use all the time,” Saltmere says.

“We’ve used it for building shelters, making beds, and as a glue in making instruments like spears and boomerangs. And we know that the oils and the waxes can be used to treat wounds and in other medicines.

“In Aboriginal culture, a product like that becomes a sacred thing. It belongs to country, and to us that’s what ‘sacred’ means.”

Led by AIBN’s Professor Darren Martin with Dr Nasim Amiralian and Dr Pratheep Annamalai, the early research found that the nanofibres from spinifex improved the physical properties of latex.

And that means making condoms “as thin as a human hair without any loss in strength”, might just be possible.

“The nanofibres that we can extract are long, thin and stretchy,” says Martin. “Only a few nanometres wide but thousands of nanometres in length.

“As a materials scientist, this is exactly what we look for when we want to reinforce flexible materials.

“We can make a stronger and thinner membrane that is supple and flexible, which is the holy grail for natural rubber.”

The latex formulation was tested in 2015 with promising results.

AIBN director Dr Alan Rowan now says spinifex can survive in temperatures up to 60°C and puts down roots to 30 metres below ground to find water.

“The grass produces a resin (that) can form a very strong bond when used as glue and which, once melted and solidified again, forms a polymer that resembles Bakelite,” he says.

Traditional knowledge is used only via agreement with the knowledge custodians, a requirement of the United Nations Convention on Biological Diversity.

The Myuma Group are a forerunner in such agreements, having helped reform the Queensland Biodiscovery Act in 2020.

“For thousands of years, spinifex was a building block for the Aboriginal societies in the desert,” says Saltmere, also an adjunct researcher at UQ.

“Now it will continue to play a role in advancing local Aboriginal communities through business and employment opportunities.”