Media release

From: ARC Centre of Excellence in Synthetic Biology (CoESB)

Detecting acute heart failure in the future could be as simple as testing a  saliva sample.

Australian scientists have developed a biosensor that can rapidly detect the heart failure biomarker S100A7 in saliva,  offering a simple, non-invasive way to identify the disease.

The breakthrough, published in Biosensors and Bioelectronics: X, (https://doi.org/10.1016/j.biosx.2025.100700) could make heart failure screening more accessible, especially in remote and under-resourced communities.

Heart failure affects 64 million people worldwide but current diagnostic methods face significant limitations. Blood tests, clinical evaluations and imaging technologies are often expensive and can be geographically inaccessible, leading to delayed diagnoses when treatment options become limited.

“Early symptoms are often subtle and non-specific, meaning patients typically receive treatment only in advanced disease stages,” says first author Dr Roxane Mutschler, of the ARC Centre of Excellence in Synthetic Biology at Queensland University of Technology (QUT).

The biomarker S100A7 was discovered by Professor Chamindie Punyadeera’s team at Griffith University. Instead of using the body’s natural antibodies to detect problems, the researchers used a technique called mRNA display to custom-build their own protein detectors from scratch. They created millions of different versions and let them compete to see which ones best latched onto the heart failure marker. The winning designs were then produced in bacteria, like brewing beer, but for proteins. This synthetic biology approach is faster and cheaper than traditional methods, and the same technique can be used to detect different diseases by simply changing the target biomarker.

Co author Dr Zhengling Cui, also of QUT, says the COVID-19 pandemic has increased interest in exploring non-invasive and easily accessible biofluids for heart failure diagnostics. Saliva is increasingly being utilised to detect systemic diseases, including cancer and cardiovascular conditions, as it mirrors what’s happening in the system.

Healthy people typically have lower levels of S100A7 in their saliva, while heart failure patients have roughly twice as much. The test can detect this difference reliably.

When the team tested saliva from 31 heart failure patients, their biosensor matched results from standard medical tests 81 percent of the time. Even more importantly, it was better at correctly identifying people who didn’t have heart failure (82 percent accuracy vs 52 percent for standard tests).

Dr Mutschler says the test to diagnose or detect a variety of conditions at the point of care will alleviate the pressure on centralised testing laboratories or hospitals.

‘This work contributes to the development of personalised healthcare by aiding people to detect signs and symptoms before the onset of a condition and to easily monitor its progression.’

The study was small so researchers need to conduct wider testing before it can be used in clinics. They’re also working on improving it to handle an even wider range of protein levels.

But the early results are promising.

This same approach could work for other diseases too. The researchers say they can swap out the detection piece to look for different warning signs in the body.

‘It's like changing the attachment on a power tool, says Dr Mutschler. ‘The basic system stays the same but you can adapt it to detect different health problems.”

The research was a collaboration between QUT, CSIRO, Griffith University and several Queensland hospitals, funded by the National Health and Medical Research Council (APP2002576) and the Australian Research Council.