Method and apparatus for removing foreign matter from a flow cell of a

Abstract

A method and apparatus for removing foreign matter, including debris and deposits and air bubbles from a flow cell of a particle study device. The apparatus includes a chamber with an aperture containing unit at one end and sample and sheath introduction mechanisms at the other end to supply respectively, a sample suspension of particles and a particle free liquid. The chamber has a waste orifice positionally disposed to provide a turbulent flow of particle free liquid within the chamber upon simultaneous injection and exhaustion of the particle free liquid into and out of, respectively, the sheath introduction mechanism and the waste orifice, to remove any air bubbles in the chamber and its adjacent aperture area. The debris and deposits are first removed, in a cross-chamber process and cross-aperture process, by injecting a mixture of gas and liquid into the chamber through a first orifice in both processes, to form droplets, and exhausting the mixture from a second orifice therein and through the aperture respectfully in each process. This foreign matter is further removed by another cross-aperture step, by injecting gas into the chamber through a first orifice and producing droplets and increasing its velocity via a waste orifice of the same chamber and exhausting the gas and droplets from a second orifice through the aperture. Then, the air bubbles are removed by injecting the particle free liquid into the flow cell to form the turbulent flow and then exhausting it.