The invention provides a method, apparatus and system for separating blood
and other types of cellular components, and can be combined with
holographic optical trapping manipulation or other forms of optical
tweezing. One of the exemplary methods includes providing a first flow
having a plurality of blood components; providing a second flow;
contacting the first flow with the second flow to provide a first
separation region; and differentially sedimenting a first blood cellular
component of the plurality of blood components into the second flow while
concurrently maintaining a second blood cellular component of the
plurality of blood components in the first flow. The second flow having
the first blood cellular component is then differentially removed from
the first flow having the second blood cellular component. Holographic
optical traps may also be utilized in conjunction with the various flows
to move selected components from one flow to another, as part of or in
addition to a separation stage.