Patent ID: 8679856

Claim:
A method for carrying out the washing of particles present in suspension in a first fluid by means of a second fluid, the method comprising: i) introducing said particles suspended in said first fluid into at least one microchamber of an apparatus for manipulating particles until a first region of the at least one microchamber is completely filled; ii) introducing at least one second fluid into said at least one microchamber until a second region of the at least one microchamber is completely filled, wherein the first fluid and the at least one second fluid are introduced into the at least one microchamber in laminar flow conditions such that the first fluid and the at least one second fluid do not mix during introduction into the microchamber and do not mix when both the first fluid and the second fluid reach a stationary state; and iii) activating in said at least one microchamber at least one non-uniform field of force acting on said particles to provoke a shift of one or more of the particles alone towards one or more points of stable equilibrium generated in said at least one second region of said at least one microchamber so as to suspend said particles in said second fluid, wherein the first fluid and the at least one second fluid are in a condition of stationary state when activating the at least one non-uniform field of force in the chamber, and the first fluid and the at least one second fluid remain substantially immobile during shifting of the particles, and the at least one microchamber is delimited by a plane or floor comprising an array of electrodes for activating the at least one non-uniform field of force.