Spatial separation of particles in a particle containing solution for biomedical sensing and detection

A method for detecting an analyte, using:

• an apparatus comprising a fluid channel and one or more acoustic transducers;
• the method comprising:
• receiving, in the fluid channel, whole blood from a fluid flow path of a device, the whole blood comprising plasma and blood cells, the whole blood filling the fluid channel;
• applying, using the one or more acoustic transducers, acoustic force to the whole blood to form (i) a first layer comprising the plasma and that is substantially free of the blood cells and (ii) second layers comprising the blood cells, the first layer being between the second layers, and each of the second layers being moved toward a surface of the fluid channel;
• detecting the analyte in the first layer using an optical detector that is directed at the fluid channel while fluid flow within the fluid channel is arrested;
• and
• after detecting the analyte, releasing the acoustic force applied by the one or more acoustic transducers where, in response to the releasing the acoustic force, the plasma and the blood cells become mixed such that the whole blood is reconstituted to enable the whole blood that has been reconstituted to be in a channel downstream of the fluid channel.