Patent Publication Number: US-9415391-B2

Title: Cartridge for biochemical use and biochemical processing device

Description:
TECHNICAL FIELD 
     The present invention relates to cartridges for biochemical use and biochemical processing devices which are used to extract a living substance by biochemical reaction and conduct synthesis and analysis as necessary. 
     BACKGROUND ART 
     For example, in order to conduct gene analysis, various biochemical processes and reactions, such as extraction and amplification of nucleic acids such as DNA and RNA from a sample (also called an analyte or specimen) obtained from a living thing or the like, are needed. For these processes and reactions, several reagents must be accurately mixed with the sample. When various reagents are put in the sample and various biochemical processes are carried out, the reagents must be transported to various processing cells. 
     As a method for mixing a reagent with a sample, a pipette system based on a dispensing robot is often used in automatic analyzing devices, etc. as described in Patent literature (PTL)  1 . A dispensing robot is a unit which drives a dispensing mechanism two-dimensionally or three-dimensionally within a given area of the device and automatically sucks in and discharges a liquid through a nozzle, tip or the like at the tip of the dispensing mechanism. 
     On the other hand, in the field of gene analysis, there is a DNA amplifying process called PCR reaction (Polymerase Chain Reaction). In the field of gene analysis, DNA to become a template must be amplified by PCR reaction until a detector can detect it and this is known as a very effective method. 
     When handling DNA or RNA, it is necessary to prevent non-target DNA or RNA from getting mixed (hereinafter referred to as contamination). PCR may amplify a minute trace (one molecule) of DNA as a template. Therefore, it is necessary to prevent low-molecular clone DNA or DNA fragments (PCR product) amplified by PCR from being contaminated and becoming a template. To this end, a chamber in which DNA as a target of extraction, etc. is handled and a chamber in which PCR is conducted should be separated, and DNA aerosol contamination should be prevented by transporting a sample through a tube containing the sample, and PCR reaction should be conducted under a clean bench. 
     In the case of the pipette system which uses a dispensing robot as described in PTL 1, contamination is prevented by cleaning the nozzle or throwing away the tip. However, since the nozzle or tip moves in the air, it is very difficult to prevent DNA aerosol contamination. For this reason, the chamber in which DNA is handled and the chamber in which PCR is conducted are separated and work is done under a clean bench to reduce contamination as far as possible. 
     In recent years, researches have been promoted in which a sample is reacted with a reagent in a microspace using a microdevice to perform a series of processes including extraction, purification, amplification, and analysis of a living substance. A microdevice may be used for a wide variety of applications including gene analysis. The use of a microdevice offers the following advantages: consumption of samples and reagents is smaller than with an ordinary device; it is easier to carry than when various reagents are set; and it is disposable. In addition, since reaction in a small device is completed in an enclosed space, it is considered to address the above problem of contamination easily. PTL 2 proposes a technique of extracting DNA using a preprocessing tip as an example of application of a microdevice. 
     CITATION LIST 
     Patent Literature 
     [PTL 1] Japanese Patent Application Laid-Open No. S63 (1988)-315956 
     [PTL 2] Japanese Patent Application Laid-Open No. 2007-330179 
     SUMMARY OF INVENTION 
     Technical Problem 
     In order to mix small amounts of reagent and sample to conduct chemical reaction and analysis in a microdevice, quantitative control of fluids such as the reagent and sample in the microdevice is important. The reason is that chemical reaction and analysis cannot be made as expected unless appropriate amounts of reagent and sample are transported at an appropriate time. Therefore, the flow rate, flow velocity, fluid pressure, etc. of the fluid to be transported must be controlled properly. 
     As methods for transporting liquids in a microdevice, there are a centrifugal method and a method in which air pressure is encapsulated directly in a flow channel. In the both methods, it is difficult to transport liquids under a condition sealed from the external air, so there is concern about the possibility of DNA aerosol contamination. In addition, it is difficult to control the fluid flow rate and fluid transporting time. 
     The present invention intends to provide a disposable cartridge for biochemical use which solves the above problem, is shielded from the external air, and enables easy flow rate control of liquids such as reagents, as well as a biochemical processing device using the same. 
     Solution to Problem 
     (1) A cartridge for biochemical use according to the present invention includes a chamber as a liquid transport source for encapsulating a reagent to be transported, a chamber as a liquid transport destination for the reagent, and a liquid transport channel for connecting them, in which these chambers and the liquid transport channel are sealed in a cartridge body, the liquid transport channel is formed and an elastomer membrane is pasted on the bottom of the cartridge body, and part of the membrane is one wall surface of the liquid transport channel and constitutes a pneumatic diaphragm pump mechanism which reciprocates according to change in pressure given from outside and changes the volume of the liquid transport channel. 
     For example, the cartridge for biochemical use includes a chamber for encapsulating a liquid sample, a chamber for encapsulating a reagent, and a plurality of chambers in which a series of processes for extracting and purifying a living substance as a target from the mixed liquid as the liquid sample mixed with the reagent are performed sequentially. Also it includes a liquid transport channel which connects mutually related chambers among these chambers. These chambers are sealed in the cartridge body. On the bottom of the cartridge body, the liquid transport channel is formed and a membrane as an elastomer is pasted. Part of the membrane is one wall surface of the liquid transport channel and constitutes a pneumatic diaphragm pump mechanism which reciprocates according to change in pressure given from outside and changes the volume of the liquid transport channel. 
     (2) A biochemical processing device according to the present invention includes the following constituent elements in addition to the cartridge for biochemical use: namely a cartridge holder which holds the cartridge and has an air pressure applying part to apply air pressure to activate the membrane as the pump mechanism; and an air supply/exhaust mechanism connected to an air pressure source to control supply of the air pressure to the cartridge holder and exhaust thereof. 
     Advantageous Effects of Invention 
     According to the cartridge for biochemical use in the present invention described above in (1), in a closed space, a reagent and a sample can be transported in a noncontact manner and biochemical processing can be performed, so contamination can be prevented. 
     According to the biochemical processing device in the present invention described above in (2), the air supply/exhaust mechanism for driving the valve mechanism to open and close the liquid transport port of each chamber of the cartridge and the air pressure applying part for activating the liquid transport pump mechanism (membrane) of the cartridge are located in the cartridge holder, so the size and cost of the cartridge can be reduced. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a partially omitted perspective view showing the general structure of a biochemical processing device according to an embodiment of the present invention. 
         FIG. 2  is a structure diagram of an air pressure control system used in the above embodiment. 
         FIG. 3  is a diagram of direction control by three-way valves used in the air pressure control system in a normal state and an energized state. 
         FIG. 4  is a longitudinal sectional view of a cartridge for biochemical use used in the above embodiment. 
         FIG. 5  is a longitudinal sectional view of a cartridge holder used in the above embodiment. 
         FIG. 6  is a longitudinal sectional view showing the initial state of the cartridge loaded on the cartridge holder. 
         FIG. 7  is an explanatory view showing the cartridge and a cartridge operation sequence. 
         FIG. 8  is an explanatory view showing the cartridge and the cartridge operation sequence. 
         FIG. 9  is an explanatory view showing the cartridge and the cartridge operation sequence. 
         FIG. 10  is an explanatory view showing the cartridge and the cartridge operation sequence. 
         FIG. 11  is an explanatory view showing the cartridge and the cartridge operation sequence. 
         FIG. 12  is an explanatory view showing the cartridge and the cartridge operation sequence. 
         FIG. 13  is an explanatory view showing the cartridge and the cartridge operation sequence. 
         FIG. 14  is an explanatory view showing the cartridge and the cartridge operation sequence. 
         FIG. 15  is an explanatory view showing the cartridge and the cartridge operation sequence. 
         FIG. 16  is an explanatory view showing the cartridge and the cartridge operation sequence. 
         FIG. 17  is a plan view showing the general structure of the cartridge. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Next, embodiments of the present invention will be described by taking an example, referring to drawings. 
     The biochemical processing device according to an embodiment of the present invention as shown in  FIG. 1  exemplifies a device which performs a series of processes from extraction of DNA to its amplification as an example of nucleic acid extraction and amplification. The biochemical processing device includes three units: a cartridge  1  for biochemical use which performs the above series of processes in a closed condition; a cartridge holder  2  which holds the cartridge  1  and has an air pressure applying part to open and close the liquid transport channel of the cartridge  1  and enable the cartridge  1  to perform pumping operation; and an air pressure control system  3  which is connected to an air pump (air pressure source)  10  and controls supply of air pressure to the cartridge holder  2  and exhaust thereof. 
     First, the general structure of the cartridge  1  as an example is described, referring to  FIG. 17 .  FIG. 17  is a plan view showing the outline of the cartridge  1 . 
     The cartridge  1  includes a sample encapsulating chamber  39  for encapsulating a liquid specimen (hereinafter called a sample) including a living substance; reagent encapsulating chambers for encapsulating various reagents (for example, a solution encapsulating chamber  38  for encapsulating a solution for nucleic acid extraction, a cleaning liquid encapsulating chamber  71  for encapsulating a cleaning liquid, an eluent encapsulating chamber  72  for encapsulating an eluent, and an amplifying reagent encapsulating chamber  73  for encapsulating an reagent for PCR amplification); a plurality of chambers in which a series of processes to extract and purify a living substance (DNA in this example) as a target from a mixed liquid as a mixture of a liquid sample and a reagent are performed (for example, a agitating chamber, a living substance adsorbing chamber  74 , and a waste liquid chamber  75 ); a chamber  76  for nucleic acid amplification; and liquid transport channels  36  ( 36   a  to  36   g ). In each liquid transport channel  36 , when the liquid transport port provided in the corresponding chamber is opened by a valve mechanism (which will be described later), the liquid can circulate and a pump mechanism (which will be described later) is used for this circulation. In the explanation give below, the liquid transport channels  36   a  to  36   g  enable the liquid to flow in a related process and while the liquid is flowing, the relevant liquid transport channel is held open by the valve mechanism and the other liquid transport channels are closed by the valve mechanism. 
     In this embodiment, the sample encapsulating chamber  39  also serves as a chamber for introducing a reagent (solution) from the reagent encapsulating chamber (solution chamber)  38  through the liquid transport channel  36   a  and preparing a mixed liquid. Furthermore, it also serves as a chamber for agitating the mixed liquid. Agitating will be described later. Alternatively the chamber for preparing a mixed liquid and the chamber for agitating may be provided separately from the sample encapsulating chamber  39 . 
     In the sample encapsulating chamber  39 , the nucleic acid in the sample is exposed by a solution (dissolution step) and after the dissolution step, the mixed liquid is introduced from the sample encapsulating chamber  39  through the liquid transport channel  36   e  into the living substance adsorbing chamber  74 , where the target nucleic acid is made to adsorb onto the surface of a carrier provided in the adsorbing chamber  74  (adsorption step). 
     The mixed liquid introduced into the adsorbing chamber  74  is transported through a liquid transport channel  36   g  to the waste liquid chamber  75 . After the adsorption step, the cleaning liquid is transported from the cleaning liquid encapsulating chamber  71  through the liquid transport channel  36   b  to the adsorbing chamber  74  and the components other than the nucleic acid as the target on the carrier surface are cleaned (cleaning step). The waste cleaning liquid is guided through the liquid transport channel  36   g  into the waste liquid chamber  75 . After the cleaning step, the eluent from the eluent encapsulating chamber  72  is transported through the liquid transport channel  36   c  to the adsorbing chamber  74 . Consequently, the nucleic acid adsorbed on the carrier surface leaves the carrier and is transported through the liquid transport channel  36   f  to the reaction chamber  76  for nucleic acid amplification together with the eluent (elution step: nucleic acid extraction). After that, the reagent required for PCR amplification is transported from the amplifying reagent encapsulating chamber  73  through the liquid transport channel  36   d  to the reaction chamber  76 . The reagent required for PCR amplification is a mixture of primer, Taq polymerase and nucleotide (dNTP) with a buffer solution and this is mixed with the eluent containing the above extracted nucleic acid (template DNA) to become a reaction solution. 
     The reaction solution in the reaction chamber  76  is temperature-controlled by a thermal cycler (not shown) built in the cartridge holder  2  to perform nucleic acid amplification by the PCR method. After the nucleic acid amplification step, the reaction solution is transported through a capillary tube (not shown) connected to the liquid transport channel  36   i  and the cartridge  1  to a capillary electrophoresis DNA sequencer (not shown) where DNA analysis takes place. 
     Next, the structures of the cartridge  1  and cartridge holder  2  will be described referring to  FIGS. 4 to 6 . 
       FIG. 4  is a longitudinal sectional view of the cartridge  1  (taken along the line A-A in  FIG. 1 ), showing the reagent encapsulating chamber (solution encapsulating chamber)  38 , the sample encapsulating chamber  39 , and the liquid transport channel  36  ( 36   a ). The abovementioned other chambers  71  to  76  and liquid transport channels  36   b  to  36   g  are similar to the chambers and liquid transport channel as shown in  FIG. 4  in terms of the relation between a chamber and a liquid transport channel, so their cross section structures are omitted. 
     As shown in  FIG. 4 , in the cartridge  1 , the cartridge body  30  has the reagent encapsulating chamber  38 , the sample encapsulating chamber  39 , and a groove to become the liquid transport channel  36   a  which connects these chambers. The groove  36   a  is formed on the bottom of the cartridge body  30 . A membrane  31  is pasted on the bottom of the cartridge body  30 . Part of this membrane  31  serves as one face of the liquid transport channel  36   a  and constitutes a pump mechanism which reciprocates according to change in the pressure given from outside to change the volume of the liquid transport channel. 
     The reagent (solution) required to process the sample is previously encapsulated in the reagent encapsulating chamber  38 . In the other various reagent encapsulating chambers  71 ,  72 , and  73  as well, the respective reagents are encapsulated similarly. In order to prevent the reagent from flowing to the liquid transport channel  36  (liquid transport channel  36   a  in  FIG. 4 ) during storage, a plug  35  is provided at the liquid transport port  38 A between the reagent encapsulating chamber (solution encapsulating chamber  38  in  FIG. 4 ) and the liquid transport channel  36   a . Between the chambers, a very small vent groove (or vent hole)  37  is provided above the chambers. A top cover  32  is attached to the cartridge body  30  so as to cover the chambers and vent groove  37  and a film  33  is pasted on the top cover  32  to make the inside of the cartridge  1  sealed. The vent groove  37  has a function to make the pressure level equal between the chambers and ensure that circulation in the liquid transport channel  36  and reciprocating motion of the membrane  31  are smooth. 
     As shown in  FIG. 17 , the sample encapsulating chamber  39  is connected to the adsorbing chamber  74  through the liquid transport channel  36   e  and as shown in  FIG. 4 , a liquid transport port  39 B as one upstream end of the liquid transport channel  36   e  is also provided at the exit of the sample encapsulating chamber  39 . A plug (not shown) similar to the plug  35  provided at the liquid transport port  38 A is provided at the liquid transport port  39 B as well. 
     Taking mass production into consideration, it is desirable that the components used in the cartridge  1  be made of a mold-formable material. It is desirable that the cartridge body  30  is made of acrylic resin, polycarbonate resin, quartz or the like and the membrane  31  be made of heat-resistant and weather-resistant silicon rubber, PDMS or the like. It is manufactured by pasting these together chemical treating or with an adhesive agent or double-faced tape. The top cover  32  is made of the same material as the cartridge body  30  and the inside of the cartridge  1  is sealed by ultrasonic welding of the peripheries of the chambers. 
     In the cartridge  1 , various reagents are previously encapsulated in the chambers and the cartridge  1  is supplied to the user as it is. On the other hand, the user has to encapsulate a sample in the sample encapsulating chamber  39 . In doing so, the user removes the rubber plug  34  attached to the top cover  32  of the cartridge  1 , puts the sample in it, reattaches the rubber plug  34  to seal the sample encapsulating chamber  39 . 
       FIG. 5  is a sectional view of the cartridge holder  2 , taken along the line A-A in  FIG. 1 , which corresponds to the cartridge  1  in  FIG. 4 . It shows, as an example, an air cylinder mechanism to open and close the reagent encapsulating chamber  38  and sample encapsulating chamber  39  shown in  FIG. 4  and an air supply/exhaust mechanism for air pressure to drive the membrane (liquid transport pump). Though not shown in  FIG. 4 , the air supply/exhaust mechanism and air cylinder mechanism for the other chambers and liquid transport channels are also provided in the cartridge body  30  in the same way as shown in  FIG. 4 . Next, the air cylinder mechanism and air supply/exhaust mechanism will be described. 
     In the cartridge holder  2 , a cartridge holder body  50  has an air cylinder mechanism and an air supply/exhaust mechanism which are driven by the air pressure control system  3  when the cartridge  1  is loaded, as shown in  FIGS. 6 to 16 . 
     The air cylinder mechanism includes a plurality of pin-like plungers (plungers  51  and  52  are shown in  FIGS. 5 to 16 ) which are built in the cartridge holder body  50  and activated by change in air pressure, and air pressure ports (air pressure ports  58  to  62  are shown in  FIGS. 5 to 16 ) which introduce the air pressure to be applied to these plungers. The air pressure is, for example, positive pressure but it may be negative pressure. The plunger  51  deforms part of the membrane  31  elastically to open and close the liquid transport port  38 A of the reagent encapsulating chamber  38 . The plunger  52  deforms part of the membrane  31  elastically to open and close the liquid transport port  39 A. Therefore, part of the membrane  31  works as a valve which is activated by the air cylinder mechanism. Gaskets  53  and  55  are fitted to the bases of the plungers  51  and  52  respectively. Gaskets  54  and  56  are also fitted near the top ends of the plungers  51  and  52 . Also, the cartridge holder body  50  has a sealing projection  57  on its top surface to crush part of the membrane  31  and seal the surroundings of the liquid transport channel  36  of the cartridge  1  when the cartridge  1  is loaded. Since the air pressure ports  58  to  62  are connected to the corresponding three-way valves  14  of the air pressure control system  3  respectively, the plungers  51  and  52  can be separately controlled. 
     Preferably the cartridge holder body  50  should be made of acrylic resin. The larger the number of liquid transport points in the cartridge  1  is, the more complicated the air pressure flow path of the cartridge holder body  50  is. If it is made of acrylic resin, joining or bonding can be done, so the problem of a complicated flow path can be addressed. Since the number of cylinders in the air cylinder mechanism increases with increase in the number of liquid transport points, preferably it should be made of a rigid resin such as PPS resin. However, if it is made by molding, air leakage from a parting line may occur, and care must be taken not to cause such leakage. As gaskets for pneumatic reciprocation, the gaskets  53 ,  54 ,  55 , and  56  have vacuum grease coated on their sliding parts. Consequently, sliding friction is reduced when the plungers  51  and  52  are driven. 
     As shown in  FIG. 6 , when the cartridge  1  is loaded on the cartridge holder  2 , the sealing projection  57  of the cartridge holder body  50  crushes part of the membrane  31  and seals the surroundings of the liquid transport channel  36  as mentioned above. The air pressure port  60  is intended to push up the plunger  51 . The air pressure port  59  is intended to move the plunger  51  back to its original position. The air pressure port  62  is intended to push up the plunger  52 . The air pressure port  61  is intended to move the plunger  52  back to its original position. Each port is connected to a pipe from the air pressure control system  3 . Consequently, the air pressure control system  3  supplies air pressure to each port and the plungers of the air cylinder mechanism are activated individually. 
     The air pressure port  58  supplies air pressure to an air pressure applying part  50 A. This causes part of the membrane  31  to be deformed elastically and pressed against the liquid transport channel  36 . A groove  50 A, which is opposite to the liquid transport channel  36  across the membrane  31  when the cartridge  1  is loaded on the cartridge holder  2 , is provided on the top surface of the cartridge holder body  50 . This groove  50 A is communicated with the air pressure port  58  and serves as the above air pressure applying part to deform part of the membrane  31  elastically. The groove  50 A is surrounded by the projection  57 . The air port  58  and groove  50 A serve as an air supply/exhaust mechanism to give air pressure to reciprocate the membrane  31  as a pneumatic diaphragm pump mechanism. 
     Air pressure is not supplied to the cartridge holder  2  merely by connecting the pipes of the air pressure control system  3  to the air pressure ports. In the normal state, all the ports of the cartridge holder  2  are open to the atmosphere under the directional control by the three-way valves  14  (see  FIG. 3 ). 
       FIG. 2  shows the structure of the air pressure control system  3 . The air pump  10  as an air pressure drive source sucks in and discharges air. The discharged air passes through a pipe and through an air filter  11  and an air pressure regulating valve  12  and is guided to the IN side of a three-way valve manifold  13 . A plurality of three-way valves  14  are serially mounted on the three-way valve manifold  13  and each connected with a common air flow path. Each of the three-way valves  14  is connected to a pipe. The three-way valves  14  are controlled individually. When a three-way valve  14  is energized, the manifold  13  is connected to the cartridge holder  2  and the air from the air pump  10  passes through a speed controller  15  and is guided to the cartridge holder  2 . The three-way valve manifold  14  also has an OUT side flow path for air exhaust which is open to the atmosphere. A silencer  16  is attached to the exit of the OUT side flow path. 
     As the air discharged from the air pump  10  passes through the air filter  11 , dirt and dust contained in the air are removed. This prevents foreign matter from entering the three-way valves  14  and speed controllers  15 . Also, the air pressure regulating valve  12  can regulate the air pressure given to the cartridge holder  2  to an appropriate pressure. Since the three-way valves  14  are mounted on the three-way valve manifold  13 , all the pipes are connected at a single point. Even if the number of three-way valves  14  is increased, the pipes are connected at one point and thus they can be housed in a compact manner. A speed controller  15  is connected to the pipe connected to each three-way valve  14  so that the air pressure flow rate can be controlled. Here, since a liquid is transported pneumatically by reciprocating motion (pumping motion) of the membrane  31 , flow rate control is important. Also, since a sound is made when the pipe with high pressure is made open to the atmosphere, the silencer  16  is provided on the OUT side exit to turn down the sound volume. 
       FIG. 3  is a view which shows direction control by the three-way valves  14  of the air pressure control system  3 . 
     The pipes are here arranged so that an air pressure flow path  17  extending from the IN side to the cartridge holder  2  and an air pressure flow path  18  extending from the cartridge holder  2  to the OUT side are each switched by the three-way valves  14 . A three-way valve  14  is normally closed and in the normal state, the air pressure flow path  17  is closed and the air pressure flow path  18  is connected. At this time, the air coming from the IN side is connected to the three-way valve manifold  13 , but the air pressure flow path  17  is closed, so no air pressure is applied to the cartridge holder  2 . However, since the air pressure flow path  18  is open, the flow path on the cartridge holder  2  side and the OUT side are open to the atmosphere. When the three-way valve  14  is energized, the air pressure flow path  17  becomes open and the air pressure flow path  18  becomes closed. At this time, the air coming from the IN side is guided to the three-way valve manifold  13  and since the air pressure flow path  17  is open, the air can be transported to the cartridge holder  2 . Also, since the air pressure flow path  18  is closed, the air pressure can be given to the cartridge holder  2 . Since the pipes are connected to the cartridge holder  2  through the three-way valves  14 , the air pressure can be given to a desired flow path. 
     Next, liquid transporting operation in the cartridge  1  with this structure will be explained referring to  FIGS. 7 to 19 . As a preparation for transporting a liquid, first, the air pump  10  is driven before connecting the cartridge holder  2  to the air pressure control system  3 . At this time, since the three-way valves  14  are in the normal closed state, the pressure between the air pump  10  and the three-way valves  14  increases. In this condition, the pressure is regulated to an appropriate level by the pressure regulating valve  12 . After that, each three-way valve  14  is energized to open the air pressure flow path  17  and close the air pressure flow path  18 . Consequently, air is sent to the cartridge holder  2  through the pipe and in this condition, the flow rate in each pipe connected to the cartridge holder  2  is controlled by the speed controller  15 . After regulation of the air pressure and flow rate is finished, the cartridge holder  2  is connected to the air pressure control system  3  and the cartridge  1  is loaded on the cartridge holder  2 . 
     Then, first the three-way valve  14  of the air pressure port  59  and the three-way valve  14  of the air pressure port  61  are switched so that these ports are communicated with the air pressure supply side. Consequently, the plunger  51  and plunger  52  move down as shown in  FIG. 7 . This condition is considered to be the plunger initial position. Then, the three-way valve  14  of the air pressure port  60  is switched so that the air pressure port  60  is communicated with the air pressure supply side, and the three-way valve  14  of the air pressure port  59  is switched so that the air pressure port  59  is communicated with the atmosphere. Consequently, the air pressure accumulated in the air pressure port  59  becomes open to the atmosphere and the air pressure from the air pressure port  60  is applied, so the plunger  51  is pressed against the cartridge  1  by the air pressure as shown in  FIG. 8 . The plunger  51  pushes up the plug  35  closing the reagent encapsulating chamber  38  through the membrane  31 . This releases the plug  35  closing the reagent encapsulating chamber  38 . The plug  35  once released is kept pushed up so that it remains released after that. However, since the plunger  51  is held pressed between the reagent encapsulating chamber  38  and the liquid transport channel  36 , the area between the reagent encapsulating chamber  38  and the liquid transport channel  36  remains closed. 
     Then, the three-way valve  14  of the air pressure port  58  is switched so that the air pressure port  58  is communicated with the air pressure supply source. This causes air pressure to be introduced into the groove (air pressure applying part)  50 A and part of the membrane  31  is pushed by the air pressure to contact the liquid transport channel  36 , as shown in  FIG. 9 . Consequently, the air staying in the liquid transport channel  36  is pushed out into the sample encapsulating chamber  39 . Meanwhile the pressure in the cartridge  1  goes up since the inside of the cartridge  1  is sealed. Between the reagent encapsulating chamber  38  and the sample encapsulating chamber  39 , the vent groove  37  lies above the chambers, so the pressures in the chambers are equalized. 
     Then, the three-way valve  14  of the air pressure port  62  is switched so that the air pressure port  62  is communicated with the air pressure supply source and the three-way valve  14  of the air pressure port  61  is switched so that the air pressure port  61  is communicated with the atmosphere. Consequently, the air pressure accumulated in the air pressure port  61  becomes open to the atmosphere and since the air pressure from the air pressure port  62  is applied, the plunger  52  is pushed up toward the cartridge  1  by the air pressure as shown in  FIG. 10 . The plunger  52  is pressed between the sample encapsulating chamber  39  and the liquid transport channel  36  through the membrane  31 , so the area between the sample encapsulating chamber  39  and the liquid transport channel  36  is closed. 
     Then, the three-way valve  14  of the air pressure port  60  is switched so that the air pressure port  60  is communicated with the atmosphere and the three-way valve  14  of the air pressure port  59  is switched so that the air pressure port  59  is communicated with the air pressure supply source. Consequently, the air pressure accumulated in the air pressure port  60  becomes open to the atmosphere and since the air pressure from the air pressure port  59  is applied, the plunger  51  returns to its original position as shown in  FIG. 11 . The membrane  31  remains under the air pressure from the air pressure port  58 , so it is held pressed against the liquid transport channel  36 . 
     Then, the three-way valve  14  of the air pressure port  58  is switched so that the air pressure port  58  is communicated with the atmosphere. Consequently, the air pressure accumulated in the air pressure port  58  becomes open to the atmosphere and as shown in  FIG. 12 , the membrane  31  pressed against the liquid transport channel  36  is restored to its original position by its own elastic force and the pressure inside the cartridge  1 . At that time, the plunger  52  forces the sample encapsulating chamber  39  and the liquid transport channel  36  to remain closed, so the reagent from the reagent encapsulating chamber  38  flows into the liquid transport channel  36  and the air from the sample encapsulating chamber  39  passes through the vent groove  37  and moves into the reagent encapsulating chamber  38 . 
     Then, the three-way valve  14  of the air pressure port  60  is switched so that the air pressure port  60  is communicated with the air pressure supply source and the three-way valve  14  of the air pressure port  59  is switched so that the air pressure port  59  is communicated with the atmosphere. Consequently, the air pressure accumulated in the air pressure port  59  becomes open to the atmosphere and the air pressure from the air pressure port  60  is applied, so the plunger  51  is again pressed against the cartridge  1  as shown in  FIG. 13 . At this time, again the plunger  51  closes the area between the reagent encapsulating chamber  38  and the liquid transport channel  36  but the reagent remains in the liquid transport channel  36 . 
     Then, the three-way valve  14  of the air pressure port  62  is switched so that the air pressure port  62  is communicated with the atmosphere and the three-way valve  14  of the air pressure port  61  is switched so that the air pressure port  61  is communicated with the air pressure supply source. Consequently, the air pressure accumulated in the air pressure port  62  becomes open to the atmosphere and the air pressure from the air pressure port  61  is applied, so the plunger  52  returns to its original position as shown in  FIG. 14 . 
     Then, again the three-way valve  14  of the air pressure port  58  is switched so that the air pressure port  58  is communicated with the air pressure supply source. Consequently, as shown in  FIG. 15 , the membrane  31  is pressed by the air pressure and forced to contact the liquid transport channel  36 . At that time, the area between the reagent encapsulating chamber  38  and the liquid transport channel  36  is held closed by the plunger  51 , so the reagent accumulated in the liquid transport channel  36  flows into the sample encapsulating chamber  39 . As a result, the encapsulated sample is mixed with the reagent. 
     Then, again the three-way valve  14  of the air pressure port  61  is switched so that the air pressure port  61  is communicated with the atmosphere and the three-way valve  14  of the air pressure port  62  is switched so that the air pressure port  62  is communicated with the air pressure supply source. Consequently, the air pressure accumulated in the air pressure port  61  becomes open to the atmosphere and the air pressure from the air pressure port  62  is applied, so the plunger  52  is held pressed against the cartridge  1  as shown in  FIG. 16 . At this time, the plunger  52  closes the area between the sample encapsulating chamber  39  and the liquid transport channel  36 . 
     As the operation shown in  FIGS. 10 to 16  is repeated, the reagent encapsulated in the reagent encapsulating chamber  38  is transported to the sample encapsulating chamber  39 . This makes it possible to transport a liquid in the sealed cartridge  1  without contact with a fluid. By repeating this operation a number of times, the entire reagent in the chamber can be transported, whether the amount of reagent is very small or large. However, after purification, reaction, etc., in some cases, not all the reagent in the chamber but only a given amount of reagent should be transported. In such a case, the given amount of reagent can be transported by controlling the number of repetitions of this operation. 
     More specifically, according to this embodiment, when the cartridge is loaded on the cartridge holder, the plungers are driven by air pressure control to seal or open the liquid transport port of each chamber. Furthermore, the membrane is pressed against the liquid transport channel by air pressure and the volume (shape) of the liquid transport channel can be changed by air pressure. Consequently, the liquid transport channel functions as a pump to move the fluid inside. By a combination of these movements, the liquid can be transported without contact with a fluid in the sealed cartridge. 
     This structure is given to each liquid transport channel between mutually related chambers among all the chambers of the cartridge  1  so that various reagents can be transported at a desired time by the same operation as above. In addition, when purification, reaction, or agitation is done, the area between chambers can be sealed arbitrarily and thus fluid control can be done stably. 
     In this embodiment, by supplying a prescribed amount of reagent to the sample encapsulating chamber  39 , the sample is mixed with the reagent, and in the sample encapsulating chamber  39 , the abovementioned pump function of the membrane  31  may be used for agitating. 
     For example, in a condition in which the reagent has been supplied to the sample encapsulating chamber  39  and the sample stays mixed with the reagent in the sample encapsulating chamber  39  (condition shown in  FIG. 16 ), the liquid transport port  38 A of the chamber connected to the sample encapsulating chamber  39  (which also serves as a agitating chamber) through the liquid transport channel  36  (the reagent encapsulating chamber  38  in this embodiment) is closed. In this condition, only the sample encapsulating chamber  39  is communicated with the liquid transport channel  36  and the reciprocating motion of the membrane  31  in the liquid transport channel  36  is repeated. The reciprocating motion of the membrane causes part of the liquid (sample-reagent mixture) in the sample encapsulating chamber  39  to be repeatedly pulled and pushed, back and forth, between the sample encapsulating chamber  39  and the liquid transport channel  36 , so that the liquid in the sample encapsulating chamber  39  is agitated. Although the sample encapsulating chamber  39  also has the function as an agitating chamber in this embodiment, alternatively the above operation may be performed while a sample encapsulating chamber and a agitating chamber are separated from each other. 
     Consequently, reagent mixing, agitating, purification, reaction, etc. can be performed while contamination with DNA floating in the air is prevented. 
     In this embodiment, a series of processes from nucleic acid extraction to amplification are conducted in the cartridge, but instead, processes from nucleic acid extraction to purification may be performed in the cartridge. 
     There are many kinds of reagents required for preprocessing in gene analysis. In these circumstances, when this system is adopted, it can handle many reagents though the drive source is only the air pump  10  of the air pressure control system  3 . In addition, even if another cartridge  1  is added to the device, by installing an additional three-way valve  14  and an additional pipe in this system, the system can work without an additional drive source. Therefore, the system may be considered to be a versatile system. Furthermore, the device cost can be reduced and the device can be more compact. 
     In this embodiment, the valve function for the liquid transport channel is given only by the membrane  31  in the cartridge  1  and the air cylinder mechanism to drive it is built in the cartridge holder  2 , so the cartridge  1  itself can be structurally simplified. Since the cartridge  1  is disposable, reduction in the unit price of the cartridge  1  leads directly to reduction in running cost. 
     As an example of application of this embodiment, the valve function in this embodiment may be provided in the cartridge. For example, a check valve (one-way valve) may be installed at the point of sealing by a plunger in the cartridge so that the liquid transport channel is deformed by air pressure to transport the liquid. As methods for providing a built-in check valve, the following methods are available: a method which uses a commercial check valve and has it built in, a method which uses a rubber ball and gives it a check valve function, and a method in which a membrane is formed into a three-dimensional shape and two such membranes are pasted together. Consequently, the structure of the cartridge holder is simplified and the device cost can be reduced. However, since the check valve is built in the cartridge, the price of the cartridge is higher. 
     When the membrane makes up a pump mechanism based on air pressure as in this embodiment, the liquid can be transported while fluid control is easily done. As another example of application, instead of deforming the liquid transport channel  36  by air pressure, the chambers, including the reagent encapsulating chamber  38 , may be deformed by air pressure. Instead of air pressure, a different thing such as a roller may be used for deformation. 
     According to this embodiment, the amount of transported liquid varies depending on how the membrane  31  is deformed. If the amount of liquid which can be transported by deforming the membrane  31  once is to be controlled, desirably the membrane  31  should be elastically deformed until it completely contacts the liquid transport channel  36 . The amount of transported liquid can be controlled by changing the volume of the liquid transport channel  36  according to the amount of elastic deformation of the membrane  31 . 
     Basically, the cartridge  1  is cryopreserved in order to suppress degradation in the previously encapsulated reagent. However, due to the existence of the vent hole  37 , there is a possibility that the reagent may move into another chamber through the vent groove  37  when the cartridge is unfrozen. For this reason, after the cartridge is unfrozen, it must be handled carefully. On the other hand, a valve structure which opens the vent groove  37  only when positive or negative pressure is applied to the inside of the chamber of the cartridge  1  may be provided, in which the top cover  32  is an elastic molded article. Alternatively, it is also possible that the vent groove  37  is abolished and the inside of the chamber to which the liquid is first transported is kept pressurized and sealed to transport the liquid. As the liquid is transported, the inside of the chamber to which it is first transported is depressurized and the inside of the chamber to which it is transported next is pressurized. This helps deforming the membrane  31 . 
     The plug  35  is used to seal the reagent chamber, etc. before its use and once unplugged, it loses the function as a plug. Here, when the plug  35  is slightly pushed up, the liquid transport channel  36  is made open. This means that the liquid transport channel can be made open without removing the plug  35  completely. It is also possible that the plug  35  is made of a material with low specific gravity such as polypropylene resin or EPDM and removed completely by the plunger (pin) force so as to float on the reagent. Alternatively, it may be made of a magnetic material and removed by the magnetic force; or it may be made of wax or the like and melted by heat; or it may be made into a fragile film or fragile shape so that its sealing part is broken and opened by the plunger force. Another possible approach is to make an attachment for storage of the cartridge and provide a structure which closes the reagent encapsulating chamber  38  and the liquid transport channel  36  while the cartridge is set in the attachment. In the first place, the plug  35  may be removed; in that case, the reagent may be put in a capsule to prevent the reagent from flowing into the liquid transport channel  36  during storage. The capsule may be melted by heat or the solvent to dissolve the capsule may be previously put in. 
     As for the three-way valves  14  of the air pressure control system  3 , the air pressure port  58  and air pressure port  60  may be integrated. In that case, the motion to push up the plunger  51  and the motion to press the membrane  31  against the liquid transport channel  36  occur simultaneously, which poses no problem in transporting the liquid. Also, by using a spring to drive a plunger in a direction, the number of three-way valves  14  can be decreased. Here, when air pressure is given from the air pressure port  58  to press the membrane  31  against the liquid transport channel  36 , a descending force is applied to the plungers  51  and  52 . This force may be used to move down the plungers. This eliminates the need for the air pressure ports  59  and  61 , so the number of three-way valves  14  can be further decreased. The number of three-way valves  14  can be decreased by adopting various methods as mentioned above to make the device more compact and reduce the device cost. In addition, the three-way valve manifold  13  and the cartridge holder body  50  may be integrated and by doing so, redundant pipes can be decreased to achieve more compactness and further cost reduction. Five-way valves may be used in place of the three-way valves  14 . 
     In this technique, various processes can be conducted in the cartridge  1  by providing a temperature-controllable reaction chamber in the cartridge  1  in addition to the chamber for mixing the sample with the reagent and performing thermal control. Also when gene analysis is conducted using a capillary electrophoresis DNA sequencer, all preprocessing steps from DNA extraction to amplification are carried out in the cartridge  1  in advance and after preprocessing, the capillary is connected so that a series of processes for DNA analysis can be performed on a single device. The series of processes for DNA analysis includes PCR. Therefore, gene analysis such as expression analysis can also be made by conducting PCR with this technique and directly detecting PCR reaction optically. 
     Examples of the present invention have been so far explained, but the present invention is not limited thereto and it is understood by those skilled in the art that various modifications may be made within the scope of the present invention described in the claims. It is also within the scope of the present invention to combine embodiments as appropriate. In the above embodiment, nucleic acid, particularly DNA, has been described as an example of a living substance to which the present invention is applied, but it is not limited thereto but it is applicable to all living substances including RNA, proteins, polysaccharides, and microorganisms. 
     REFERENCE SIGNS LIST 
     
         
         
           
               1  . . . cartridge, 
               2  . . . cartridge holder, 
               3  . . . air pressure control system, 
               10  . . . air pump, 
               11  . . . air filter, 
               30  . . . cartridge body, 
               31  . . . membrane, 
               36  . . . liquid transport channel, 
               37  . . . vent groove 
               38  . . . reagent encapsulating chamber, 
               39  . . . sample (liquid reagent) encapsulating chamber, 
               50  . . . cartridge holder body, 
               50 A . . . air pressure applying part, 
               51 ,  52  . . . air cylinder plungers, 
               57  . . . sealing projection, 
               58 ,  59 ,  60 ,  61 ,  62  . . . air pressure ports