Flow rate optimization for the quadrupole magnetic cell sorter

The quadrupole magnetic cell sorter is a form of split-flow thin-channel (S PLITT) separation device. It employs a quadrupole magnetic field and annula r channel geometry. Immunomagnetic labels are used to bind to specific rece ptors on the surface of the cells of interest. It is the interaction of the se labels with the magnetic field that brings about the selective isolation of these cells. The SPLITT separation devices have generally been based on parallel-plate geometry, usually with effectively constant field strength applied across the channel thickness. The nonconstant field strength and an nular channel geometry of the magnetic cell sorter require that a new strat egy be developed for optimization of inlet and outlet now rates. We present such a strategy here based on a consideration of certain specific cell tra jectories within the system.