Introducing the Ketowhistle: a non-invasive, breath-based sensor for easy, real-time ketone monitoring, revolutionising diabetes management.
A sharp jab to your fingertip brings a moment of pain. A drop of blood emerges, which can be a bit unsettling. You put the drop of blood on a strip and wait for the results. Finger prick tests are simple but could never be called pleasant.
For over 1.3 million Australians living with diabetes, this invasive prick is repeated day after day, year after year, because monitoring ketone levels is crucial in managing the disease.
People with Type 1 diabetes and Type 2 diabetes treated with sodium glucose co-transporter 2 inhibitors risk diabetic ketoacidosis (DKA) due to excessive ketone production when the body, low on insulin, breaks down fats for energy. Rapid ketone buildup makes the blood acidic and toxic.
While the standard for blood ketone monitoring, the invasive nature of the finger prick test has created a barrier to routine testing, especially in children and older individuals. Additionally, the ketone test strips have a short shelf life, are single-use and are expensive.
The Australian National University (ANU) researchers Dr Shiyu Wei, Dr Buddini Karawdeniya, Prof Lan Fu and their collaborators are developing an innovative technology that will replace this invasive testing with a new method that is as simple as breathing.
Exhaled breath contains around 1,500 trace volatile organic compounds (VOCs). Our metabolism produces specific VOCs, including ketones, whose concentrations in breath change dynamically in response to metabolic shifts.
Crucially, acetone concentrations in breath directly correlate with blood ketone levels, making it a good biomarker for DKA detection.The breath-sensing method would be swift and non-invasive. However, current lifestyle monitors on the market are inaccurate, unreliable and unsuitable for diabetic monitoring.
The Ketowhistle is a portable, self-administered, real-time acetone sensor that allows diabetics to monitor their health simply by blowing a whistle.
The Ketowhistle combines this InP/chitosan nanowire array-based sensor, a CO2 sensor, signal-processing circuitry and an OLED screen display. Even better, the sensor is self-powered, so no fiddling with tiny batteries.
The Ketowhistle provides a rapid result, high selectivity for acetone and an ultra-wide sensing dynamic range from 0.04 ppm up to >110,000 ppm, easily spanning the entire breath acetone spectrum.
Developed as part of the ANU interdisciplinary research initiative ‘Our Health in Our Hands’ (OHIOH) and the ARC Centre of Excellence for Transformative Meta-Optical Systems (TMOS), the nanowire array devices for this project were fabricated and optimised at the ANFF-ACT Node. The nanowire dimensions are crucial for the device’s high sensitivity, and ANFF staff provided valuable insights for their optimisation.
In addition, an ANFF-C Gate 1 grant has enabled a market study confirming the potential market for this device.
The Ketowhistle will prevent diabetic ketoacidosis by making it easier for patients to monitor their condition. Beyond diabetes management, it could also be used to monitor ketogenic diets in weight loss plans and nutrient status in athletes. This practical device has the potential to make a positive impact on many lives, becoming as routine in clinics and homes as thermometers.
Published 15 October 2024 in ANFF’s 2024 Casebook ‘ANFF NEXT‘
Posted 5 May 2025
