Patent ID: 8821813

Claim:
A liquid-feeding chip for feeding a liquid utilizing action of centrifugal force and gravity while the liquid-feeding chin is mounted on a rotation apparatus by rotating the chip around an axis of rotation, comprising: a first storage tank provided in the chip, into which the liquid can be introduced when rotation of the chip is stopped, and two or more liquid-feeding units arranged in a plurality of levels adjacent to each other, each liquid-feeding unit being composed of a first holding tank, a second holding tank positioned in a direction of gravity with respect to the first holding tank when the chip is in use, and a channel B which extends from the first holding tank in the direction of gravity, connects the first holding tank with the second holding tank, and feeds a liquid from the first holding tank into the second holding tank by gravity, a first holding tank arranged at a first level being connected with a channel A which extends from the first storage tank toward an outer circumferential side with respect to the axis of rotation which is along the direction of gravity, wherein 1) the adjacent liquid-feeding units are connected by a channel C which extends from a second holding tank of a liquid-feeding unit arranged at an upper level to an outer circumferential side during rotation and is in communication with a first holding tank of another liquid-feeding unit arranged at a lower level, and 2) at least one of the plurality of liquid-feeding units further comprises either a) or b): a) a second storage tank positioned closer to the axis of rotation than the second holding tank, and a channel E which directly connects the second holding tank and the second storage tank, or b) a second storage tank positioned closer to the axis of rotation than the first holding tank arranged at a lower level liquid feeding unit, and a channel E which connects the first holding, tank and the second storage tank.