Abstract: A cartridge for determining a concentration of target cells within a sample includes a separation portion and a detection portion. The separation portion includes a first and second surface defining a separation chamber. The separation portion can contain a density medium having a density greater than a density of a first portion of the sample and less than a density of a second portion of the sample (that includes the target cells). The separation chamber can be fluidically coupled to an inlet reservoir such that the sample can pass from the inlet reservoir to the separation chamber during rotation. The detection portion includes a detection surface that forms a boundary of a detection chamber. The detection surface is nonparallel to the first surface such that the target cells impinge on the detection surface when passing into the detection chamber. The detection surface is configured to capture the target cells.

Abstract: A centrifugal cartridge or disk used for extraction of light supernatant fractions from fluid samples is described, particularly for non-homogenous fluid biological samples such as whole blood. The device may be used to collect cell-free blood plasma or a fraction of whole blood containing target cells such as leukocytes. Single or multiple channels are described, including channels with passive valves, gaskets, receiving cavities, inlet holes, capillary wicking ridges, distal cavities for cell retention, separator gel, and density medium. Centrifugal action causes whole blood in a receiving cavity to pass into one or more channels where it separates into blood cells, plasma and optionally fractions of an intermediate density. After spin, the plasma returns to the receiving cavity by way of the one or more channels for extraction through the inlet hole or other inwardly located hole.

Abstract: A cup used to receive, hold, measure and pour liquids, such a specimens, such as for a medical assay, is described. The cup comprises an open receiving upper chamber, two or more open sample-directing channels, and an open, calibrated and marked measuring column. When sitting on a level surface, fluid flows freely from the upper chamber through the sample-directing channels into the measuring column. A foot is under each fluid-directing channel. The base of the measuring column functions as an additional, such as a third, foot. Cups nest, with the two feet of the upper cup sitting into two sample-directing columns of lower cup. The measuring column and upper chamber taper to permit nesting. If the cup is tipped, it rests on two of three of: the two feet and the base of the measuring column, and a point on a lower perimeter of the upper chamber, such that fluid will not spill.

Abstract: A cup used to receive, hold, measure and pour liquids, such a specimens, such as for a medical assay, is described. The cup comprises an open receiving upper chamber, two or more open sample-directing channels, and an open, calibrated and marked measuring column. When sitting on a level surface, fluid flows freely from the upper chamber through the sample-directing channels into the measuring column. A foot is under each fluid-directing channel. The base of the measuring column functions as an additional, such as a third, foot. Cups nest, with the two feet of the upper cup sitting into two sample-directing columns of lower cup. The measuring column and upper chamber taper to permit nesting. If the cup is tipped, it rests on two of three of: the two feet and the base of the measuring column, and a point on a lower perimeter of the upper chamber, such that fluid will not spill.