Systems and methods for concentrating biological particles in a liquid suspension use acoustic focusing technology. In some instances, the systems and methods include extracting and separating a target material from the concentrated biological particles in the liquid suspension. Algae cells can be concentrated and lipids isolated from the algae for the production of biofuel.
ACKNOWLEDGEMENT OF GOVERNMENT SUPPORT
 This invention was made with government support under Contract No. DE-AC52-06NA25396 awarded by the U.S. Department of Energy. The government has certain rights in the invention.