Described as “hearts on a chip,” the engineered heart tissues are produced through 3D bioprinting with a bio-ink developed in Savoji’s laboratory using patient-harvested stem cells, enabling personalized human heart models to be created.
An initial version of the technology was publicized two years ago, in a study in Applied Materials Today.
The new study marks a major step forward: the direct integration of ultra-soft, biocompatible and fluorescent mechanical sensors within the heart tissue itself. These sensors allow for unprecedented precision in measuring the contractile forces generated at both the cellular level and across the entire tissue, using non-destructive optical methods.
Unlike existing “heart-on-a-chip” platforms—often limited in their ability to capture localized forces within dynamic 3D tissues—this approach delivers high-resolution, real-time, mechanical data. It therefore more accurately reflects the complexity of the human myocardium, the muscle responsible for cardiac contraction.
The researchers also measured calcium activity within the tissues, visualizing in real time the calcium waves that trigger each heartbeat. They further demonstrated that their “hearts on a chip” respond to drugs just like real cardiac tissues, confirming the model’s sensitivity for pharmacological screening.