New Sensor 'Listens' to Mini-Hearts, Poised to Transform Cardiac Drug Development

A team of engineers and cardiovascular researchers has developed a wireless, non-invasive sensing platform that monitors how miniature lab-grown human heart tissues beat—by effectively "listening" to the ripples they create in a liquid medium. The work, published in Nature Sensors, could accelerate drug development, improve cardiac safety testing, and reduce reliance on animal models.

The new system, known as a biomechanical-well-plate (BWP), was developed by researchers at UNSW Sydney in partnership with the Victor Chang Cardiac Research Institute (VCCRI). Instead of directly measuring tissue motion with microscopes, the BWP detects tiny pressure changes generated when a cardiac organoid contracts while submerged in liquid—similar to how ripples spread when a stone is dropped into water. A highly sensitive silicon-based sensor beneath the liquid captures these pressure variations and converts them into electrical signals, providing a continuous, real-time readout of tissue behaviour.

Addressing a technological bottleneck

Current methods for monitoring cardiac organoids rely heavily on optical imaging, which requires filming tissues under microscopes and performing extensive post-recording data processing. This process is time-consuming, difficult to scale, and can disrupt the delicate culture environment. Some techniques also require physically attaching or constraining the tissue, which can alter its natural behaviour.

"The problem that we want to address is to develop a new tool that supports biological study on human organoids that overcome existing limitation in animal models," said Scientia Associate Professor Hoang-Phuong Phan, the corresponding author from UNSW. "The advantage of these organoids over animal models is the organoid can be cultured from human cells, so physiologically they are more relevant in drug testing. They are also much cheaper, and they can be cultured in a large quantity of sample."

Phan added: "What we have developed is a very simple tool that allows us to directly quantify the mechanic and physiological behaviour of the organoids without using microscope."

How the technology works

The BWP was inspired by the fish lateral line—a row of tiny sensors along a fish's body that detects movement and pressure changes in water, helping them sense nearby objects, predators, and prey.

"What we do is to place the organoid in a chamber filled with liquid and then we measure the contractions through the pressure propagated inside the liquid medium," explained Dr. Chi Cong Nguyen, an Associate Lecturer at UNSW and the first author of the paper.

Associate Professor Timothée Mouterde from The University of Tokyo, a co-corresponding author, elaborated: "It's relatively similar to phenomenon as how ripples are created on a pond when you throw in a stone. When the organoid contracts we get a very small deformation at the liquid surface and we are able to measure that using a highly sensitive silicon-based sensor."

"From those readings, which happen in real-time, we can calculate the dynamic response of the organoid, how it is developing and how it is responding to any drugs that are being administered in testing. All of that information is reflected in the vibration signal that we can capture with very precise sensors," Mouterde said.

Implications for drug development and personalised medicine

Because the system monitors changes in real time, researchers can observe exactly how a cardiac organoid responds when a drug is introduced and how that response evolves. This could make drug development faster and more reliable by identifying promising treatments earlier and filtering out compounds unlikely to work in humans.

Dr Jordan Thorp, a co-author from VCCRI, highlighted the inefficiency of current preclinical models: "We know that a very large percentage of drugs (about 90%) in development that have been tested on animals then fail in clinical trials. By using human organoids we can bypass that step and go straight to checking if the drugs are suitable for people, saving significant time and money."

The technology could also support personalised medicine. "We can even take stem cells from an individual patient and effectively grow a mini-replica of their own heart to test how they would react to certain drugs, because we know that different patients can react to the same drug in different ways," said Associate Professor Adam Hill, the corresponding author from the Victor Chang Institute. "It would also help clinicians to test different doses of drugs for each individual patient to optimise the best protocol for them."

Reducing reliance on animal testing

The research, partially funded by the NSW Non-animal Technologies network (NAT-Net), aligns with a broader global shift toward reducing animal models. Regulatory bodies are increasingly encouraging alternative approaches, and tools that make organoid research more practical and scalable are expected to play an important role.

"New approach methodologies, including human stem-cell-derived organoids, are quickly moving from specialist research tools into mainstream drug discovery and regulatory science," Hill said. "In cardiac safety testing, the momentum is particularly strong. However, there is a clear need for robust, scalable sensors that can measure organoid contraction in a reproducible, high-throughput way. Technologies like this one will help us identify cardiotoxic drugs (search)Search drug earlier and develop safer and more effective therapies."

Challenges and future directions

Despite its promise, the technology remains at an early stage. Scaling up the system is a key priority—while the current prototype can measure multiple samples, researchers aim to expand to larger formats for high-throughput screening. Sensor consistency and manufacturing at low cost with reliable performance across large batches also require further engineering.

The research team—a cross-institutional collaboration including Scientia Associate Professor Thanh Nho Do and Scientia Professor Nigel Lovell (UNSW Sydney), together with Dr Syamak Farajikhah and Dr Ann-Na Cho (The University of Sydney)—also aims to boost sensor sensitivity, which would allow smaller organoids with weaker signals to be studied. Beyond cardiac research, the platform could be adapted for other organoid types, including neuromuscular tissue.

The work underscores the longstanding collaboration between UNSW and VCCRI, linked by an affiliation agreement in place since 1995, focused on improving outcomes for people living with cardiovascular disease (search)Search disease.