Abstract: The disclosure relates to an apparatus for segregating particles on the basis of their ability to flow through a stepped passageway. At least some of the particles are accommodated in a passage bounded by a first step, but at least some of the particles are unable to pass through a narrower passage bounded by a second step, resulting in segregation of the particles. The apparatus and methods described herein can be used to segregate particles of a wide variety of types. By way of example, they can be used to segregate fetal-like cells from a maternal blood sample such as maternal arterial blood.

Abstract: The disclosure relates to an apparatus for segregating particles on the basis of their ability to flow through a stepped passageway. At least some of the particles are accommodated in a passage bounded by a first step, but at least some of the particles arc unable to pass through a narrower passage bounded by a second step, resulting in segregation of the particles. The apparatus and methods described herein can be used to segregate particles of a wide variety of types. By way of example, they can be used to segregate fetal-like cells from a maternal blood sample such as maternal arterial blood.

Abstract: The invention relates to methods of using an apparatus to sequester thrombi (including emboli) from blood of an animal such as a human. The apparatus comprises a stepped or sloped separation element interposed between an inlet region and an outlet region of a void that can be filled with fluid. The void can be enclosed within a cover and fluid flow through the void engages cells and thrombi/emboli in a blood sample with the separation element. Only particles (e.g., blood cells) which have or can deform to have a characteristic dimension smaller than or equal to the distance between a step and the cover or body can pass onto or past a step. By selecting dimensions which permit blood cells, but not thrombi or emboli, to pass onto or past a step and passing fluid through the apparatus, thrombi/emboli can be sequested from the blood sample. The thrombi can be observed, removed, or treated to effect their degradation or lysis.

Abstract: The disclosure relates to an apparatus for segregating particles on the basis of their ability to flow through a stepped passageway. At least some of the particles are unable to pass through a narrower passageway bounded by a segregating step, resulting in segregation of the particles. The breadth of the leading edge of at least one step of the apparatus is significantly greater than the overall width of the passageway in which the step occurs, permitting high and rapid sample throughput. The apparatus and methods described herein can be used to segregate particles of a wide variety of types. By way of example, they can be used to segregate circulating tumor cells from a human blood sample.

Abstract: The invention relates to microscale cell separating apparatus which are able to separate cells on the basis of size of the cells, interaction of the cells with surfaces of the apparatus, or both. The apparatus comprises a stepped or sloped separation element (16) interposed between an inlet region (20) and an outlet region (22) of a void that can be tilled with fluid. The void can be enclosed within a cover (12) and fluid flow through the void engages cells with the separation element. Only cells which have (or can deform to have) a characteristic dimension smaller than or equal to the distance between a step and the cover or body can pass onto or past a step. Modifications of surfaces within the apparatus can also inhibit passage of cells onto or past a step.

Abstract: The invention relates to microscale cell separating apparatus which are able to separate cells on the basis of size of the cells, interaction of the cells with surfaces of the apparatus, or both. The apparatus comprises a stepped or sloped separation element (16) interposed between an inlet region (20) and an outlet region (22) of a void that can be tilled with fluid. The void can be enclosed within a cover (12) and fluid flow through the void engages cells with the separation element. Only cells which have (or can deform to have) a characteristic dimension smaller than or equal to the distance between a step and the cover or body can pass onto or past a step. Modifications of surfaces within the apparatus can also inhibit passage of cells onto or past a step.

Abstract: The disclosure relates to an apparatus for segregating particles on the basis of their ability to flow through a stepped passageway. At least some of the particles are accommodated in a passage bounded by a first step, but at least some of the particles are unable to pass through a narrower passage bounded by a second step, resulting in segregation of the particles. The apparatus and methods described herein can be used to segregate particles of a wide variety of types. By way of example, they can be used to segregate fetal-like cells from a maternal blood sample such as maternal arterial blood.