Acoustophoretic Motion of Leishmania spp. Parasites

The analysis of cell motion in an acoustic field is of interest as it can lead to new methods of cell separation, isolation and manipulation for diagnosis and treatment of diseases. Studies of the motion of different species of Leishmania parasites during exposure to ultrasonic standing waves in a microfluidic device allowed identification of acoustic responses of these parasites in their promastigote and amastigote forms. Both forms exhibited a positive acoustic contrast factor and were driven toward the pressure node established in the center of the channel by the acoustically induced radiation force (F_R). Promastigotes experience calculated F_R amplitudes one order of magnitude larger than those experienced by amastigotes because of the measured differences in volume. The aggregates formed at the pressure node have distinct shapes and stability conditions, for both promastigotes and amastigotes.