Systems and methods for parallel channel microfluidic separation

A method comprising:

• providing a fluid cleansing device comprising:
• a first substrate comprising:
• a first plurality of microfluidic channels defined in a first face of the first substrate, wherein each of the first plurality of microfluidic channels comprises an upstream portion and a downstream portion;
• a second plurality of microfluidic channels defined in a second face of the first substrate, wherein each of the second plurality of microfluidic channels comprises an upstream portion and a downstream portion;
• and
• a plurality of connecting channels coupling the downstream portion of the first plurality of microfluidic channels to the upstream portion of the second plurality of microfluidic fluid channels;
• a second substrate coupled with the first face of the first substrate, the second substrate defining a wall of the first plurality of microfluidic fluid channels;
• and
• a third substrate coupled with the second face of the first substrate, the third substrate defining a wall of the second plurality of microfluidic fluid channels, wherein at least one of the first substrate, the second substrate, or the third substrate is configured to couple with a base substrate comprising one or more acoustic transducers;
• flowing a fluid comprising particles through the first plurality of microfluidic channels;
• and
• directing, with an acoustic wave generated by the one or more acoustic transducers, the particles to a first aggregation axis of each of the first plurality of microfluidic channels.