Measuring Entropy Production Rates. A Unipd Study


Researchers from the universities of Barcelona and Padua have developed a revolutionary methodology for measuring entropy production on dimensions one million times smaller than one centimeter. With affiliations from Universität Göttingen and Universidad Complutense, the Variance sum rule for entropy production study was published in the international peer-reviewed journal Science.

Despite many efforts, measuring entropy production at the nanoscale remains challenging. This study links entropy production to the flow of heat across the surface of the red blood cells that dissipates energy in the diluted fluid. Using precise calorimetry measurements, the result obtained is a million billion smaller than one calorie per second - a plate of pasta is equivalent to around 250 calories.

Operationally, the research teams detected heat flow resulting from active metabolic forces within red blood cells by observing the emerging flickering on their cell membrane. This flickering is the result of the incessant movement of molecular motors, the molecules that consume sugar to restructure cells.

"Heat is a symptom of cell health, and this finding could open up new ways to determine tissue health," explains lead researcher Professor Felix Ritort, Institute of Nanoscience and Nanotechnology, University of Barcelona. He adds, "Characterizing the entropy production in living systems is crucial for understanding the efficiency of energy conversion processes