Researchers at the Helmholtz Zentrum Muenchen and Technische Universitaet Muenchen (TUM) have developed a heart model called Langendorff heart to demonstrate the impact of artificial nanoparticles on the heart rhythm and heart rate.
By using the heart model, a separated rodent heart filled with nutrient solution as substitute for blood, the researchers were able to find the mechanism behind the influence of nanoparticles on the heart rate. To perform the experiment, they improved the experimental setup of Langendorff to reflow the nutrient solution once again into the heart, allowing them to refine substances discharged by the heart and study the reaction between the nanoparticles and the heart.
The researchers tested titanium dioxide and carbon block nanoparticles, spark-generated carbon, silicon dioxide, various Aerosil silicas and polystyrene by using the heart model. During the tests, they observed that silicon dioxide, titanium dioxide, spark-generated carbon and carbon black increased the heart rate by up to 15% with modified ECG values that did not stabilize, even after the exposure to nanoparticles was stopped. However, polystyrene and Aerosil silicas did not affect the function of the heart. The smaller size and larger surfaces of nanoparticles offer them special properties.
The new heart model could be effective in medical research where the use of artificial nanoparticles as drug delivery agents is continuously increasing. However, the impact of these nanoparticles on the human body is not clear. The Langendorff heart can be used a test organ to identify the nanoparticles that have no negative effect on the heart. According to Andreas Stampfl, one of the researchers, the heart model features the sinus node and an impulse generator, which makes it to work outside the body for many hours. Moreover, the modifications in the heart function can be clearly detected utilizing the ECG chart and the heart rate.