Early detection of micro blood clots: Tracing the blood
Dübendorf, 31.03.2026 — By the time micrometer-sized blood clots are detected, it may already be too late. Empa researcher Peter Nirmalraj and his team are investigating the occurrence and composition of these tiny blood clots, aiming to assess medication efficacy and individual patient risk more accurately.
A stroke is life-threatening. When a blood clot impairs the oxygen supply to the brain, every second counts. Various factors increase the risk of thrombosis. These include diabetes, obesity and Long COVID, a condition that occurs after a coronavirus infection. This increases the risk of complications in blood clotting. Up to 30% of coronavirus patients are affected by Long COVID after their recovery, which can have devastating effects on their health. How microclots in the blood of Long COVID patients affect cardiovascular and neurological risks is not yet fully understood.
Empa researcher Peter Nirmalraj and his team want to work up a comprehensive understanding of blood clots in patients with stroke, COVID complications or rare types of dementia such as vascular dementia, which is caused by strokes. Together with Susanne Wegener from the University of Zürich, the researchers utilize various imaging and measurement methods to precisely characterize blood clots of stroke patients based on their composition, shape and size. Furthermore, they investigate how various clots react to different treatment methods.
To allow everyone to benefit from the collected data and findings, the team wants to provide the model on an open source platform. This enables earlier detection of blood clotting complications and more accurate prediction of individual stroke risk. The project can be carried out thanks to the generous donations from the Peter Bockhoff foundation, the Theodor Naegeli Foundation, the Immanuel und Ilse Straub Foundation, as well as two other Foundations.
Further information
Dr. Peter Nirmalraj
Transport at Nanoscale Interfaces Laboratory
Phone +41 58 765 43 35
peter.nirmalraj@empa.ch