Inhomogeneity of ultrasound field during sonication experiments in vitro and its influence on the overall amount of ultrasound energy entering a sonication vessel

Anotace: Current sonication experiments in vitro show immense variability in experimental set-ups and equipment used. Many factors such as presence of standing waves or position of sonicated sample in ultrasound field during the experiment affect ultrasound field parameters the sonicated samples actually experience. The main goal of this work was to quantify influence of position of sonicated sample on maximum acoustic intensity and overall amount of ultrasound energy entering sonication vessel when placed at different distances from ultrasound transducer. The measurements were performed in a water sonication tank with use of a circular unfocussed ultrasound transducer (d = 19 mm) and needle hydrophone (d = 0.5 mm). The measurements showed that the differences in amount of ultrasound energy (maximum and minimum energy were compared) entering particular well per time unit at different distances from ultrasound transducer range from 45.5% (48-well culture plate) to 109.9% (96-well culture plate). Moreover, the maximum acoustic intensity of ultrasound field entering particular well can differ by up to 233.2%. Therefore, position of sonicated sample in ultrasound field should not be neglected during sonication experiments in vitro.