Patent ID: 7371330
Filing Date: 2008-05-13
Classification: B01D,B01L,G01N,Y10T

Abstract:
1. A method for performing sedimentation of a particle suspension, using micro-fluidic structures comprising an inflow channel comprising an azimuthal path length and determining the flow rate, wherein an inflow channel inlet is arranged radially further inwardly than an inflow channel outlet, as well as a separation chamber with a particle accumulation region, and an outflow channel, which are formed in a rotation body, wherein a portion of the inflow channel with an azimuthal path length leads into the separation chamber, comprising: imparting the rotation body with rotation at the given rotation frequency, in order to feed a defined particle suspension volume by centrifugal force through the inflow channel into the separation chamber at a position radially inward with respect to the particle accumulation region; sediment the particle suspension in the separation chamber, so that particles accumulate in a radially outward particle accumulation region of the separation chamber due to their higher mass density as compared with a liquid in the particle suspension; and at least partially draining off supernatant liquid developing by the sedimentation by centrifugal force through an outflow channel fluidically connected to the separation chamber, wherein the inflow channel comprises such a radial slope, such a length and such a cross section that, at a given rotation frequency and the defined particle suspension volume, the flow rate of the particle suspension into the separation chamber is so low that an inflow of a particulate phase in the separation chamber is forced along a wall spaced from an outflow channel inlet, so that an interface forming between supernatant liquid and a particulate phase in the separation chamber remains radially outside an outflow channel inlet, at which the outflow channel is fluidically connected to the separation chamber.