Abstract: Transducer assemblies that can be used in acoustophoretic systems are disclosed. The acoustophoretic systems including the transducer assemblies and methods of operating the acoustophoretic systems are also disclosed. The transducer assemblies include a housing, a polymeric film attached to the housing, and a piezoelectric material attached to the polymeric film. The piezoelectric material is not attached to, and does not come in direct contact with, the housing. The piezoelectric material is configured to be driven by a drive signal to create a multi-dimensional acoustic standing wave. The piezoelectric material can be attached to the polymer film by an adhesive coating on the polymer film.

Abstract: Acoustic perfusion devices and processes for separating biomolecules from other material in a fluid mixture are disclosed. The devices include an inlet port, an outlet port, and a collection port that are connected to an acoustic chamber. An ultrasonic transducer creates an acoustic standing wave in the acoustic chamber that permits a continuous flow of fluid to be recovered through the collection port while keeping the biological cells within the acoustic chamber to be returned to the bioreactor from which the fluid mixture is being drawn.

Abstract: A series of multi-dimensional acoustic standing waves is set up inside a growth volume of a bioreactor. The acoustic standing waves are used to hold a cell culture in place as a nutrient fluid stream flows through the cell culture. The nutrient fluid stream dislodges some cells from the cell culture, which can then be recovered for cell therapy applications. The cell culture continues to expand and reproduce, permitting continuous recovery of cells from the bioreactor.

Abstract: Systems and methods for increasing the accuracy of a turbidity sensor are disclosed. The systems include a turbidity sensor and a flow module with a specialized flow path, with the turbidity sensor engaging with the flow module such that a measurement zone of the turbidity sensor is disposed within a flow path of the flow module and a bypass path of the flow module does not pass through the measurement zone. The methods include flowing a fluid containing bubbles into a system that separates the fluid in the flow module into a first stream of fluid containing relatively more bubbles and a second stream of fluid containing relatively fewer bubbles, the first stream flowing through a bypass path that does not pass through the measurement zone, and the second stream flowing through the measurement zone of the turbidity sensor.

Abstract: Acoustic perfusion devices for separating biological cells from other material in a fluid mixture are disclosed. The devices include an inlet port, an outlet port, and a collection port that are connected to an acoustic chamber. An ultrasonic transducer creates an acoustic standing wave in the acoustic chamber that permits a continuous flow of fluid to be recovered through the collection port while keeping the biological cells within the acoustic chamber to be returned to the bioreactor from which the fluid mixture is being drawn.

Abstract: A perfusion bioreactor includes at least one ultrasonic transducer that can acoustically generate a multi-dimensional standing wave. The standing wave can be used to retain cells in the bioreactor, and can also be utilized to dewater or further harvest product from the waste materials produced in a bioreactor.

Abstract: Multi-stage acoustophoretic devices for continuously separating a second fluid or a particulate from a host fluid are disclosed. Methods of operating the multi-stage acoustophoretic devices are also disclosed. The systems may include multiple acoustophoretic devices fluidly connected to one another in series, each acoustophoretic device comprising a flow chamber, an ultrasonic transducer capable of creating a multi-dimensional acoustic standing wave, and a reflector. The systems can further include pumps and flowmeters.

Abstract: Devices for separating materials from a host fluid are disclosed. The devices include a flow chamber, an ultrasonic transducer, and a reflector. The ultrasonic transducer and reflector create an angled acoustic standing wave oriented at an angle relative to the direction of mean flow through the flow chamber. The angled acoustic standing wave results in an acoustic radiation force having an axial force component that deflects the materials, so that the materials and the host fluid can thus be separated. The angled acoustic standing wave can be oriented at an angle of about 20° to about 70° relative to the direction of mean flow through the flow chamber to deflect, collect, differentiate, or fractionate the materials from the fluid flowing through the device at flow rates of about 400 mL/min up to about 700 mL/min.

Abstract: Provided herein are systems and methods for separation of particulate from water using ultrasonically generated acoustic standing waves.

Abstract: Acoustophoretic devices and methods for separating biological cells (particularly T-cells) from other fluids/materials using multi-dimensional acoustic standing waves are disclosed. The devices include an inlet, at least two outlets, and a flow chamber having an ultrasonic transducer-reflector pair. Specifically, T cells, B cells, or NK cells can be separated from other blood components. A dual-pass acoustophoretic system including two acoustophoretic devices arranged in series and fluidly connected to one another is also illustrated. Means for pre-chilling the mixture prior to separation in the devices or system can be used to improve retention, concentration, and clarification and to prevent outgassing.

Abstract: An acoustic standing wave is utilized to separate components from a multi-component fluid, such as oil from an oil-water mixture, in a fluid flow scheme with an acoustophoresis device. For example, the flow scheme and device allows for trapping of the oil as the oil coalesces, agglomerates, and becomes more buoyant than the water.

Abstract: Separation of particles or droplets from a host fluid may be achieved using a transducer and/or reflector that is a thin, non-planar structure. The thin non-planar structure improves operation of an acoustic standing wave generated by an acoustic transducer. The structure may operate as a pressure release boundary and may be constructed as plastic film.

Abstract: Acoustophoretic devices and methods for concentrating targeted biological cells in a reduced volume using multi-dimensional acoustic standing waves are disclosed. The methods include flowing a mixture of a host fluid and the biological cells through an acoustophoretic device. The acoustophoretic devices include an inlet, an outlet, and a flow chamber having an ultrasonic transducer-reflector pair. Biological cells, such as T cells, are separated from a host fluid for utilization in allergenic or autologous cell therapies. The disclosed devices and methods are capable of concentrating biological cells to at least 100 times their original cell concentration. The disclosed methods and devices are further capable of decreasing an original feed volume to a final concentrated volume that is less than one percent of the original feed volume.

Abstract: A system for removing lipids from blood during cardiopulmonary bypass surgery is disclosed. The system uses an acoustophoretic separator having improved trapping force. The transducer of the acoustophoretic seperator includes a ceramic crystal. Blood flows through the separator, and lipids are trapped and removed.

Abstract: Devices and methods for inspecting, detecting, isolating, monitoring, characterizing, or separating pathogens in blood containing blood cells are disclosed. The devices include a flow chamber having a solvent inlet, at least one host-fluid inlet, a particulate outlet, at least one residual outlet, and a reflector. The methods include trapping the pathogens in the acoustic standing wave, introducing a solvent into the flow chamber, and removing the pathogens from the device. Devices and methods for inspecting, detecting, isolating, monitoring, characterizing, or separating specialized circulating cells in blood containing blood cells are also disclosed. The devices include a flow chamber having at least one inlet and at least one outlet, and a microscope objective and a cover glass. The methods include driving the transducer to create an acoustic standing wave in the flow chamber and microbubbles in the blood.

Abstract: Methods for generating particulate clusters and nodal trapping lines having desired widths are disclosed. The devices include an acoustic chamber having an inlet and an outlet. An ultrasonic transducer and reflector create a multi-dimensional acoustic standing wave that generates particulate clusters separated by a channel of fluid running therebetween and creates nodal trapping lines. The frequency of the multi-dimensional acoustic standing wave can be selectively tuned so as to selectively control at least one of (a) a width of each particulate cluster, or (b) a width of each channel of fluid. The frequency of the multi-dimensional acoustic standing wave can also be selectively tuned so as to selectively control the width of each nodal trapping line. Also disclosed are particulate clusters separated by a channel of fluid, wherein a ratio of the widths of the particulate clusters and the channel of fluid can be varied as desired.

Abstract: A flow chamber is provided through which is flowed a mixture of a fluid and a particulate. The flow chamber comprises at least one multi-phase water inlet through which multi-phase water enters the flow chamber, a water outlet through which water exits the flow chamber, a solids outlet through which particles having a density at or above a pre-defined threshold exit the flow chamber, and a low density outlet through which particles having a density below the pre-defined threshold exit the flow chamber. Also provided are one or more ultrasonic transducers and one or more reflectors corresponding to each transducer to acoustically filter the fluid and cause particles/fluid to be selectively diverted to one of the outlets. Related apparatus, systems, techniques and articles are also described.

Abstract: A system having improved trapping force for acoustophoresis is described where the trapping force is improved by manipulation of the frequency of the ultrasonic transducer. The transducer includes a ceramic crystal. The crystal may be directly exposed to fluid flow. The crystal may be air backed, resulting in a higher Q factor.

Abstract: Aspects of the disclosure are directed to an apparatus for separating a second fluid or a particulate from a host fluid. That apparatus comprises a flow chamber with at least one inlet and at least one outlet. A drive circuit configured to provide a drive signal to a filter circuit configured to receive the drive signal and provide a translated drive signal. An ultrasonic transducer is cooperatively arranged with the flow chamber, and transducer includes at least one piezoelectric element configured to be driven by the current drive signal to create an acoustic standing wave in the flow chamber. At least one reflector opposing the ultrasonic transducer to reflect acoustic energy.

Abstract: An acoustophoresis device which includes a substantially vertical flow path of the fluid mixture in order to improve separation of particles/secondary fluid from a primary fluid is disclosed. The vertical flow path reduces velocity non-uniformities in the acoustic chamber resulting from gravity forces. The device includes an acoustic chamber in which multidimensional acoustic standing waves are generated. The fluid can be introduced into the acoustic chamber using a dump diffuser in which a plurality of inlets enter near the bottom of the acoustic chamber such that flow symmetry reduces both, gravity driven flow non-uniformities, and any flow interference effects between inlet mixture flow into the acoustic chamber and the continuous gravity driven particle cluster drop out.