Fluid processing device and integration with sample preparation processes

A fluid processing device comprises a substrate rotatable about a central axis of rotation and symmetrical about at least one centerline passing through the central axis of rotation, and the substrate comprises a plurality of channels, each channel comprising a respective inlet chamber and two or more respective outlet chambers. The chambers can include a plurality of individual, unconnected, input wells adapted to each receive a separate input of fluid. The channels can include flow splitters that divert at least a portion of fluid from a primary series of channels and chambers to a secondary series of channels and chambers. The diverting portions of the flow splitters can comprise at least a directional component parallel to the direction of centrifugal forces generated by rotating the substrate about its central axis of rotation. Diverting portions of flow splitters in channels on one side of the centerline can extend in a direction that is mirrored, with respect to the centerline, by diverting portions of flow splitters in channels on the opposite side of the centerline.