Perfusion systems are used in biomedical research -  especially in microphysiological systems such as organ-on-a-chip models—to simulate a realistic flow of nutrient solutions, cell culture media, or blood substitutes, thereby replicating the natural conditions found in the human body.

To achieve this, the research team has developed a novel perfusion system called HemaDyne. It is a compact, mechanical pumping mechanism that operates without additional equipment such as pressure or vacuum sources. The pump uses a type of “accordion bottle” with bellows, the volume of which is adjusted by a software-controlled piston. This generates precise pressure and flow waves. It was compared with conventional perfusion systems such as syringe pumps, peristaltic pumps, or pneumatic pumps and demonstrated significantly higher flow stability as well as faster response times.

The goal is to generate realistic hemodynamic flow profiles. A hemodynamic flow profile describes the characteristic features of blood flow in a blood vessel over time, which are influenced by the heartbeat (cardiac cycle) in the body and exhibit various phases (e.g., systole and diastole).

Using HemaDyne, for example, human endothelial cells were able to be cultured in a vascular chip for up to 60 days under physiological flow conditions—far longer than usual. The cells remained functional and showed no signs of stress or inflammation. The system was also used to investigate the influence of the diastolic resting phase (the resting phase between heartbeats) on endothelial function. The researchers found that a physiological resting phase promotes the integrity and health of endothelial cells, whereas the absence of a resting phase or an excessively long resting phase leads to cell damage. They were also able to demonstrate that age-associated, pathological flow reversals (retrograde flows) lead to endothelial dysfunction—an effect that cannot be replicated in animal models.

Original publication:
Kumar, A., Pattanshetti, S., Patel, R.D. et al. Hemadyne: accordion-inspired perfusion for microphysiological systems. Nat Commun 17, 6194 (2026). https://doi.org/10.1038/s41467-026-73722-9