Particle analyzing systems and methods using acoustic radiation pressure

A system, comprising:

• a flow path defining an axis therein;
• an acoustic gradient source configured to apply an acoustic gradient to a population of particles within the flow path,
• the acoustic gradient configured to manipulate affected particles relative to the axis;
• an interrogation site defined within the flow path,
• the interrogation site being configured to collect an optical signal from the at least some of the affected particles,
• the optical signal being indicative of at least one of scatter and emission;
• and
• an imager,
• the system being configured such that the imager images a particle that exhibits one or more defined optical signal criteria.

A method, comprising:

• communicating a fluid comprising a population of particles within a flow path defining a central axis therein;
• applying an acoustic field within the flow path to the population of particles so as to manipulate affected particles relative to the central axis of the flow path,
• interrogating at least some of the affected particles with an interrogation source to obtain an optical signal from the at least some of the affected particles,
• the optical signal being indicative of at least one of scatter and emission;
• and
• imaging, with an imager, a particle exhibiting an optical signal that meets one or more defined criteria.