Patent ID: 7392908

Claim:
A method for selectively sorting individual particles of a particular type of interest from a plurality of particles of different types, including said particles of a particular type of interest, said method comprising the steps of: (a) entraining said plurality of particles in a continuous flow of sheath liquid serving to advance said particles, one-at-a-time, along a linear path leading through and beyond an optical flow cell of a flow cytometer in which said individual particles of a particular type of interest are differentiated from other particles within said plurality of particles, and in which a discrete control signal corresponding to the differentiation of each of said individual particles of a particular type of interest is produced, to a location at which said particles are to be sorted; (b) selectively producing, in response to the production of each of said control signals, an impulsive hydraulic force that is focused on a specific particle that is located in said plurality of particles entrained in said continuous flow of sheath liquid and whose differentiation has resulted in the production of a corresponding control signal, said impulsive hydraulic force being applied at a location downstream of said optical flow cell and in a direction substantially perpendicular to said linear path, said impulsive hydraulic force being adapted to eject only said specific particle from said plurality of particles moving along said linear path within said continuous flow of sheath liquid and to eject said specific particle, together with a volume of sheath liquid that surrounds such particle as a droplet, in a direction substantially perpendicular to said linear path; and (c) collecting the individual particles ejected from said plurality of particles in a separate container.