title: Controlled cell aggregation in a pulsed acoustic field.
abstract: Cell aggregation in ultrasonic resonators can be obtained in a few seconds. Hundreds even thousands of cells can be levitated in suspension and generate 2D or 3D aggregates. Nevertheless, the aggregation rate and the 2D or 3D configurations of the resultant aggregates are very difficult to control. This work reports on a novel way of generating and controlling particle and cell aggregates using pulsed ultrasound. This technique specifically explores (in addition to the ultrasound wave, frequency and amplitude) the time of ultrasound application, i.e. the number of pulses as well as the pulse repetition frequency. We demonstrate that with pulsed ultrasound, particles and/or cells levitate in suspension, as with continuous ultrasound, and the aggregation rate can be modified in a controlled manner. By carefully tuning the number of pulses and the repetition frequency, the 3-D and 2-D configurations of the aggregates can be selectively generated. In addition, pulsed ultrasound limits transducer heating, thus allowing for higher acoustic energies than those currently employed with continuous ultrasound.
authors.affiliation: Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College, Dublin, Ireland.
authors.forename: Despina
authors.initials: D
authors.lastname: Bazou
authors.forename: Angélica
authors.initials: A
authors.lastname: Castro
authors.forename: Mauricio
authors.initials: M
authors.lastname: Hoyos
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology*; D002449:Cell Aggregation; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000473:pathology*; D004867:Equipment Design; D006801:Humans; D010316:Particle Size; D013535:Suspensions; D014159:Transducers; D014407:Tumor Cells, Cultured; D014465:Ultrasonics
chemical_list: D013535:Suspensions