Patent ID: 7842240

Claim:
A microchip for conducting an analysis, the microchip comprising: a substrate; a sample solution supply channel that is formed in the substrate and that supplies a sample solution containing a first substance; a reaction bath section that is formed in the substrate and that receives the first substance and a second substance that reacts with the first substance in the reaction bath section; a buffer solution supply channel that is formed in the substrate and that supplies a buffer solution which does not substantially react with the first and second substances; a waste solution channel that is formed in the substrate and that discharges the sample and buffer solutions to an exterior of the substrate; a first flow channel formed in the substrate and to which the buffer solution supply channel and the reaction bath section are connected, the first flow channel having first and second valves controllable between open and closed states and disposed between the buffer solution supply channel and the reaction bath section; a second flow channel formed in the substrate and to which the sample solution supply channel and the waste solution channel are connected, the second flow channel having third and fourth valves controllable between open and closed states and disposed between the sample solution supply channel and the waste solution channel; and a connecting channel formed in the substrate and connecting the first flow channel to the second flow channel, the connecting channel being disposed at an upstream side of the reaction bath section and the waste solution channel and at a downstream side of the sample solution supply channel and the buffer solution supply channel, and the first and third valves being disposed at an upstream side of the connecting channel and the second and fourth valves being disposed at a downstream side of the connecting channel such that by selectively opening and closing the first, second, third and fourth valves, the buffer solution from the buffer solution supply channel flows first into the reaction bath section at a preselected speed followed by the flow of the sample solution from the sample solution supply channel into the reaction bath section, via the connecting channel, at the preselected speed so that the first and second substances react in the reaction bath section.