Patent ID: 8617368

Claim:
An analytical tool for measurement of a biochemical sample which flows from an upstream side to a downstream side of the analytical tool, the analytical tool comprising: a substrate; a cover disposed above the substrate; the cover includes a gas discharge port; a reagent portion; an insulating film disposed on the substrate and positioned between the substrate and the cover, the insulating film having a first distal end located on the upstream side and including a first opening defining a region for accommodating the reagent portion and at least one additional opening positioned downstream from the first opening in a movement direction from the upstream side to the downstream side in which the sample moves, said at least one additional opening communicating with the first opening; the first opening including a pair of edges extending from said first distal end of the insulating film in the movement direction toward the at least one additional opening, each of the pair of edges extending from said first distal end of said insulating film toward a second end of each of the pair of edges, the second end being spaced apart from the first distal end in the movement direction; a stopper portion provided in an area surrounded by said insulating film, said stopper portion including a control edge defining a downstream edge of the region for accommodating the reagent portion so as to prevent the reagent solution to be formed in the reagent portion from spreading further in the movement direction; a flow path for moving the sample along said substrate in the sample movement direction from the upstream side to the downstream side, said flow path formed by said first opening and said at least one additional opening; and an introduction port to introduce the sample into the upstream side of the flow path, said introduction port being formed at the first distal end of the insulating film and is a part of the first opening; said gas discharging port on said cover being positioned on the downstream side of said flow path and configured to discharge gas at the downstream side of said flow path, said gas discharging port being located at a further downstream side of said at least one additional opening, to allow gas to escape from said flow path; and said reagent portion provided in said flow path; wherein at least a portion of said at least one additional opening is offset outwardly relative to the first opening in a direction perpendicular to the movement direction, the control edge of the stopper portion is substantially aligned with the second end of the pair of edges of the first opening in the direction substantially perpendicular to the movement direction, the control edge is disposed within a widthwise dimension of the first opening and in the flow path of the first opening, and the reagent portion is held in contact with the stopper portion.