Microchip and method of using microchip
There are provided a microchip provided with a liquid reagent retaining portion that retains the liquid reagent, and a usage thereof, wherein the liquid reagent is sealed into the liquid reagent retaining portion by a sealant inactive to the liquid reagent, exhibiting flowability at the time of using the microchip, and the microchip further has a separating portion to separate the liquid reagent and the sealant, connected to the liquid reagent retaining portion, and the separating portion is composed of a separation tank for separating the liquid reagent and the sealant, and an accommodation tank for accommodating a separated substance, connected to the separation tank by a first flow path.
1. A microchip comprising a liquid reagent retaining portion that retains a liquid reagent wherein
said liquid reagent is sealed into said liquid reagent retaining portion by a sealant inactive to said liquid reagent and exhibiting flowability at the time of using the microchip, wherein said sealant is disposed in a flow path connecting the liquid reagent retaining portion to a separation tank;
said microchip further has a separating portion to separate a mixture of said liquid reagent and said sealant into said liquid reagent and said sealant, connected to said liquid reagent retaining portion;
said separating portion is composed of:
(a) said separation tank for accepting the mixture and thereafter separating the mixture into said liquid reagent and said sealant by a centrifugal force applied to the microchip, and accommodating the liquid reagent separated by the centrifugal force; and
(b) an accommodation tank for accommodating the sealant separated by the centrifugal force, the accommodation tank connected to said separation tank by a first flow path;
the specific gravity of said liquid reagent is larger than that of said sealant;
said first flow path is connected to said separation tank such that said liquid reagent has a higher liquid level in said separation tank than a connection location of said first flow path to said separation tank when the centrifugal force for separating said liquid reagent and said sealant is applied to the microchip; and
said separation tank has an outlet for discharging the liquid reagent separated from the sealant.
2. The microchip according to claim 1 , wherein said first flow path has an approximately U shape.
3. The microchip according to claim 1 , wherein
contact angles of said liquid reagent and a mixture of said liquid reagent and said sealant with an inner wall of said first flow path is larger than 90°, and
said first flow path prevents said liquid reagent or said mixture leaking out to said accommodation tank as long as a centrifugal force is not applied to the microchip.
4. The microchip according to claim 1 , wherein
contact angles of said liquid reagent and a mixture of said liquid reagent and said sealant with an inner wall of said first flow path are smaller than 90°, and
said first flow path is composed of a first region that generates a capillarity of said liquid reagent or said mixture, a second region that does not generate a capillarity of said liquid reagent or said mixture, and a third region that generates a capillarity of said liquid reagent or said mixture.
5. The microchip of claim 1 wherein the outlet for discharging the liquid reagent separated from the sealant is different from the first flow path connecting the accommodation tank connected to the separation tank.