Method for transporting liquid, and microreactor

Abstract

The present invention provides a simple liquid transportation method without requiring high electric voltage or special external equipment, and a method for transporting liquid based on this transportation method. The liquid transportation method comprises a step of introducing a magnetic fluid and a liquid to be transported into a conduit or a chamber connected thereto so that the magnetic fluid and the liquid to be transported are in contact with each other directly or indirectly via a medium, a step of moving the magnetic fluid by applying a magnetic field, and a step of moving above-mentioned liquid to be transported by letting it follow the movement of the magnetic fluid. The present invention also provides a simple transportation method of a specific amount of liquid without requiring high voltage or incorporation of specific actuator components such as valves. Using a conduit wherein at least three microchannels intersect one another and at least two of them have openings which can be opened or closed, opening and closing of the openings and liquid transportation are carried out in a controlled order, so that only a specific amount from a liquid introduced in an unspecific amount, is transported.

What is claimed is:  
     
         1 . A method for transporting a liquid, which comprises transporting a liquid to be transported, in a conduit comprising a microchannel, or in a chamber connected to the conduit, by using a magnetic fluid as a piston.  
     
     
         2 . The method for transporting a liquid according to  claim 1 , which comprises the following steps: 
 (1) a step of introducing the magnetic fluid and the liquid to be transported, into the conduit or the chamber connected thereto, so that the magnetic fluid and the liquid to be transported, are in contact with each other directly or indirectly via a medium,    (2) a step of moving said magnetic fluid by applying a magnetic field, and    (3) a step of moving the liquid to be transported by letting it follow the movement of the magnetic fluid.    
     
     
         3 . The method for transporting a liquid according to  claim 2 , wherein said medium is either a gas or a liquid and is insoluble to said magnetic fluid and to said liquid to be transported.  
     
     
         4 . A microreactor comprising the following constituting elements: 
 (1) a conduit comprising a microchannel,    (2) a chamber connected to said conduit,    (3) a magnetic fluid and a liquid to be transported, introduced into the conduit or the chamber connected thereto, so that the magnetic fluid and the liquid to be transported are in contact directly or indirectly via a medium, and    (4) a magnet to apply a magnetic field to said magnetic fluid thereby to move the magnetic fluid.    
     
     
         5 . The microreactor according to  claim 4 , wherein the conduit intersects another conduit or a chamber different from the one mentioned above, so that at least two types of liquids to be transported can be mixed at the intersection.  
     
     
         6 . The microreactor according to  claim 5 , wherein said at least two types of liquids to be transported, are moved by the magnetic fluid moved solely by applying a magnetic field.  
     
     
         7 . A method for transporting a liquid, which is a method for transporting a specific amount of an optional liquid, using a conduit wherein at least three microchannels intersect one another, and at least two of them have openings which can be opened or closed, wherein opening and closing of the openings and transportation of the liquid are carried out in a controlled order, so that a specific amount from the liquid introduced in an unspecified amount is transported.  
     
     
         8 . The method for transporting a liquid according to  claim 7 , which is a method for transporting a specific amount of an optional liquid, using a conduit wherein i) first, second and third microchannels intersect one another at one intersection, ii) the first and third microchannels have first and third openings, respectively, which can be opened or closed, iii) the intersection and the second microchannel have a portion having a specific volume, which regulates the amount of the liquid filled therein, wherein a specific amount of a liquid is transported by performing a process comprising the following steps: 
 (1) opening the first opening, and closing the third opening,    (2) introducing an optional liquid into the first microchannel, and transporting the liquid until its front fills the specific volume portion,    (3) closing the first opening, and opening the third opening, and    (4) transporting the liquid filled in the specific volume portion of the second microchannel to the third microchannel.    
     
     
         9 . The method for transporting a liquid according to  claim 7 , which is a method for transporting a specific amount of an optional liquid, using a conduit wherein, i) first, second and third microchannels intersect one another at a first intersection, and the second microchannel, a fourth microchannel and a fifth microchannel intersect one another at a second intersection, ii) the first, third, fourth and fifth microchannels have first, third, fourth and fifth openings, respectively, which can be opened or closed, iii) the first intersection, the second intersection and the second microchannel have a portion having a specific volume, which regulates the amount of the liquid filled therein, whereby a specific amount of a liquid is transported by performing a process comprising the following steps: 
 (1) opening the first and fifth openings, and closing the third and fourth openings,    (2) introducing an optional liquid into the first microchannel, and transporting the liquid so that the specific volume portion is filled with the liquid,    (3) closing the first and fifth openings, and opening the third and fourth openings, and    (4) transporting the liquid filled in the specific volume portion to the third microchannel.    
     
     
         10 . The method for transporting a liquid according to  claim 7 , wherein the transportation of the liquid is performed by controlling the pressure of a gas or a liquid filled in the microchannels.  
     
     
         11 . The method for transporting a liquid according to  claim 8 , wherein the transportation of the liquid is performed by controlling the pressure of a gas or a liquid filled in the microchannels.  
     
     
         12 . The method for transporting a liquid according to  claim 9 , wherein the transportation of the liquid is performed by controlling the pressure of a gas or a liquid filled in the microchannels.  
     
     
         13 . The method for transporting a liquid according to  claim 10 , wherein the pressure control of the gas or the liquid is performed by introducing a magnetic fluid in the microchannels, and applying a magnetic field to the magnetic fluid.  
     
     
         14 . The method for transporting a liquid according to  claim 11 , wherein the pressure control of the gas or the liquid is performed by introducing a magnetic fluid in the microchannels, and applying a magnetic field to the magnetic fluid.  
     
     
         15 . The method for transporting a liquid according to  claim 12 , wherein the pressure control of the gas or the liquid is performed by introducing a magnetic fluid in the microchannels, and applying a magnetic field to the magnetic fluid.