Patent ID: 6302836
Filing Date: 2001-10-16
Classification: B01L,B04B,G01N

Abstract:
A method for partitioning and removing from a chamber a preselected phase of a sample of liquid, comprising the steps of: containing in an elongated cylindrical closed chamber having a substantially constant cross-sectional area a sample of said liquid having a plurality of phases of different densities and having a total liquid volume less than that of said chamber, and ordering said sample phases concentrically by rotating said chamber about its longitudinal axis, wherein the improvement comprises:(a) increasing the volume of said liquid in said chamber, while said chamber is rotating and said phases are ordered, by introducing into said chamber through a first rotary seal and a first cannula an inert liquid immiscible with said sample phases and having a density greater than the density of the highest density sample phase to be removed, and(b) continuing to introduce said inert liquid, thereby forcing any residual gas and at least one of said sample phases out of said chamber via a second rotary seal and a second cannulalocated substantially on the longitudinal axis of said chamber, whereby said sample phases are removed from said chamber in the order of their densities with the lowest density sample phase being removed first.