New way to ‘listen’ to mini hearts could transform drug development

Diagram to show the new biomechanical-well-plate system which detects tiny pressure changes made when organoids contract in a liquid. Image credit: UNSW

Diagram to show the new biomechanical-well-plate system which detects tiny pressure changes made when organoids contract in a liquid. Image credit: UNSW

A new sensor that can more easily monitor lab-grown heart tissue aims to speed up drug testing, enable personalised treatments, and reduce reliance on animal experiments.

Engineers have developed a new way to monitor how tiny lab-grown human heart tissues beat – by effectively ‘listening’ to the ripples they create.

The research could help accelerate drug development, improve disease modelling, and reduce reliance on animal testing, offering a more human-relevant way to study how the heart works.

The team have created a wireless, non-invasive sensing platform that can biomechanically measure how strongly the miniature heart tissues, known as cardiac organoids, beat in real time.

Cardiac organoids are 3D clusters of human heart cells grown in a laboratory that are used to evaluate the safety and efficacy of new drugs prior to clinical trials as well as study disease. While they don’t replicate the full structure of a human heart, they mimic key behaviours, especially how heart muscles contract when drugs are administered.

They are increasingly seen as a powerful alternative to animal models, which often fail to fully capture how human biology works.

Current ways of monitoring whether these cardiac organoids are working properly often rely on optical imaging, essentially filming the organoids under microscopes and analysing the footage. This process is time-consuming, difficult to scale, and can disrupt the delicate environment the tissues need to survive.

Some techniques also require physically attaching or constraining the tissue, which can alter how it behaves.

The new system, known as a biomechanical-well-plate (BWP) and developed by researchers at UNSW in partnership with cardiovascular researchers from the Victor Chang Cardiac Research Institute (VCCRI), takes a very different approach.

Instead of directly measuring motion of the tissue, it detects the tiny pressure changes created when the organoid contracts while placed in a liquid — similar to how ripples spread when a stone is dropped into water.

These tiny vibrations of the liquid surface cause the surrounding air to compress and expand. A highly sensitive sensor beneath the liquid captures these pressure variations and converts them into electrical signals.

The work, published in Nature Sensors, opens in a new window, was inspired by the fish lateral line – a row of tiny sensors along a fish’s body that detects movement and pressure changes in the water, helping them sense nearby objects, predators, prey, and other fish.

The result in terms of the BWP is a continuous, real-time readout of how the tissue is biomechanically behaving, without the need for microscopes or physical attachments.

“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, opens in a new window, 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.

“However, technologically, existing platforms to study how the organoids are biomechanically performing is still very limited. You have to put the organoid on a microscope, frequently transfer between the culture environment to the microscope which can induce contamination, move the microscope from well to well, and also do a lot of post-recording data processing.

“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.”

Faster drug testing and personalised medicine

One of the most promising applications is in drug testing.

Because the system can monitor changes in real time, researchers can see exactly how a cardiac organoid responds when a drug is introduced, as well as how that response evolves over time.

This could make drug development faster and more reliable by identifying promising treatments earlier, and filtering out those that are unlikely to work in humans.

The technology could also support the growing field of personalised medicine, where treatments are tailored to individual patients using cells derived from their own body.

“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,” said Dr. Chi Cong Nguyen, opens in a new window, an Associate Lecturer at UNSW and the first author of the paper.

“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,” added Associate Professor Timothée Mouterde from The University of Tokyo, a co-corresponding author of the paper.

“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.”

Less animal testing

The research – partially funded by the NSW Non-animal Technologies network (NAT-Net) – aligns with a broader global shift toward reducing reliance on animal models.

With regulatory bodies increasingly encouraging alternative approaches, tools that make organoid research more practical and scalable are likely to play an important role. By enabling high-throughput testing, potentially across dozens or even hundreds of samples at once, the system could significantly expand the use of human-based models in early-stage research and preclinical drug development.

“New approach methodologies, including human stem-cell-derived organoids, are quickly moving from specialist research tools into mainstream drug discovery and regulatory science,” said Associate Professor Adam Hill, opens in a new window, the corresponding author from the Victor Chang Institute.

“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 earlier and develop safer and more effective therapies.

“Beyond safety, cardiac organoids also give us a way to test medicines in human heart tissue before they ever reach a patient. 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.

“It would also help clinicians to test different doses of drugs for each individual patient to optimise the best protocol for them.”

Dr Jordan Thorp, a co-author of the paper from VCCRI, added: “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.”

Despite its promise, the technology is still at an early stage, and several challenges remain before it can be widely adopted.

Scaling up the system is a key priority. While the current prototype can measure multiple samples, researchers aim to expand this to larger formats to enable more high-throughput screening.

Consistency and manufacturing are also critical. The sensors must be produced reliably and at low cost, with consistent performance across large batches – something that requires further engineering and refinement.

The research team – a cross-institutional collaboration including Scientia Associate Professor Thanh Nho Do, opens in a new window and Scientia Professor Nigel Lovell, opens in a new window (UNSW Sydney), together with Dr Syamak Farajikhah and Dr Ann-Na Cho (The University of Sydney) – also aim to boost the sensitivity of their sensors, which would allow smaller organoids to be studied where the signals are weaker and harder to detect.

Beyond cardiac research, the platform could also be adapted for other types of organoids, including neuromuscular tissue, broadening its potential impact.

The work also highlights the strong shared focus of UNSW and VCCRI in improving outcomes for people living with cardiovascular disease, via an affiliation agreement which has been in place since 1995.

Source: UNSW