Patent ID: 8415140

Claim:
An analysis device having a microchannel structure that transfers a sample liquid towards a measurement spot by centrifugal force generated by rotating the analysis device about a rotation center and which is used to read a reactant at the measurement spot, the microchannel structure comprising: a separation cavity that separates the sample liquid into a solution component and a solid component by the centrifugal force caused by a rotation of the analysis device; a first holding section to which a part of the solid component separated by the separation cavity is transferred and which holds the part of the solid component; a connecting channel that transfers the solid component separated in the separation cavity to the first holding section; and an overflow channel, one end thereof being connected to the connecting channel and another end thereof being connected to a cavity having an air duct, the overflow channel being located adjacent to the connecting channel between the first holding section and the separation cavity; wherein a cross-sectional size g 2 of the overflow channel in the thickness direction thereof is smaller than a cross-sectional size g 1 of the connecting channel in the thickness direction thereof, and the overflow channel draws a remaining solution component contained in the solid component portion separated by the separation cavity from the connecting channel by a capillary force, wherein the solid component holding in the first holding section is transferred to the measurement spot, and wherein a width w 2 of the overflow channel in a direction intersecting a flow direction of the solution component in the overflow channel is wider than a width w 1 of the connecting channel in a direction intersecting the flow direction of the solid component at a bifurcation section of the overflow channel and the connecting channel.