JP2001249139A - Flow analysis device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an analysis device and method capable of minimizing the consumption of a reagent while avoiding troubles even if a sample solution contains suspended particulate matter, the device being inexpensive to construct. SOLUTION: The device includes a tubular main flow passage 11 through which the sample solution flows; a pump 12 for causing the sample solution to flow through the main flow passage 11; a syringe pump 14 for causing the reagent to enter the main flow passage 11 at a confluent position 15; and a detector 17 located downstream of the confluent position 15 on the main flow passage 11 for detecting a reaction between the sample solution and the reagent. The syringe pump 14 causes the reagent to intermittently enter the main flow passage 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an analysis apparatus and an analysis method using a reverse flow injection analysis method (hereinafter referred to as "inverse FIA method"), which is suitable for long-term continuous measurement such as monitoring of water quality. The present invention relates to an apparatus and an analysis method.

[0002]

2. Description of the Related Art As a simple method for measuring the components of a sample solution, a sample solution or a reagent solution is introduced into a reagent solution or a sample solution flowing in a capillary tube, and after a reaction operation or the like is performed, the sample solution or the reagent solution is provided downstream. 2. Description of the Related Art A flow injection analysis method (hereinafter, referred to as "FIA method") for detecting a target component with a detector is known. In this analysis method, a chemical reaction is performed while controlling the mixing of a reagent and a sample in a laminar flow inside a thin tube without using a reaction vessel such as a beaker or a flask, and the reaction result is detected. It is.

[0003] Among the FIA methods, a method in which a reagent solution is intermittently injected into a continuous flow system of a sample solution is called an inverse FIA. Suitable for driving.

In the conventional reverse FIA method, in order to intermittently inject a reagent solution into a sample solution, injection using a six-way valve as shown in FIGS. 16 and 17 is generally performed. FIG. 16 shows the flow path of the six-way valve at the time of reagent measurement, in which the inlet pipe 101 and the outlet pipe 102 of the main flow path are directly connected, and the sample liquid (indicated by a double line) flows from the inlet pipe 101 to the outlet. It flows directly to the tube 102. On the other hand, the reagent solution inlet pipe 103 and the outlet pipe 104 are respectively connected to the bypass 105, and the reagent solution (indicated by a thick black line) flows from the inlet pipe 103 to the outlet pipe 104 via the bypass 105. It is flowing.

FIG. 17 shows a flow path of the six-way valve at the time of reagent injection, and the same components as those in FIG. 16 are denoted by the same reference numerals. In this case, the inlet pipe 101 and the outlet pipe 102 of the main flow path are respectively connected to the bypass 105, and the sample liquid (indicated by a double line) passes through the outlet pipe 101 from the inlet pipe 101 via the bypass 105. It flows to 102. On the other hand, the reagent solution inlet tube 103 and the outlet tube 10
4 is communicated directly, and the reagent solution (indicated by a thick black line) flows directly from the inlet tube 103 to the outlet tube 104.

More specifically, when the six-way valve is switched to the state shown in FIG. 17 after the bypass pipe 105 is filled with the reagent liquid in the state shown in FIG. 16, the sample liquid flows while pushing out the measured reagent liquid into the bypass 105. On the outlet pipe 102 side of the main flow path, a part of the flow of the sample liquid can be replaced with a reagent liquid.

As described above, in the conventional reverse FIA method, a part of the sample liquid in the main flow path is replaced with the reagent liquid, whereby the sample liquid and the reagent liquid are mixed and reacted in the flow. Analysis of the target component in the sample liquid was performed by detecting.

[0008]

Even in the above-mentioned conventional reverse FIA, the amount of consumption of the reagent solution can be suppressed to some extent due to the method of injecting the reagent solution into the sample solution. However, FIG.
As shown in the above, in order to inject a certain amount of the reagent solution, the reagent solution must be flown to the bypass pipe more than the injection amount, and the excess reagent solution is discharged and wasted. Further, in the six-way valve, a sliding portion sliding for switching the flow path is precision-machined in a liquid-tight manner. Therefore, if the suspended particulate matter is present in the sample solution and enters the rubbed portion, the portion is easily damaged, and liquid leakage or the like is likely to occur. In addition, the six-way valve, which is a precision processed product, is expensive, resulting in an increase in the cost of the entire apparatus.

The present invention has been made in view of the above circumstances, and it is possible to minimize the consumption of a reagent solution, and not to cause a failure even if a sample solution contains suspended particulate matter, and It is an object of the present invention to provide an inexpensive analyzer and method.

[0010]

Means for Solving the Problems As a result of studying the above problems, the present inventors have found that a part of the main flow path is not replaced with a reagent solution from a sample solution, but intermittently joins a reagent solution to a sample solution. I thought. The difference between merging and replacement is outlined in Figure 1.
And as shown in FIG. FIG. 1 is an explanatory diagram showing a state immediately after a reagent solution 3 is joined to a sample solution 2 in a main flow path 1. FIG. 2 is an explanatory diagram showing a state immediately after a part of the main channel 1 has been replaced with a reagent solution 3 from a sample solution. In the case of merging as well, if the instantaneous flow rate of the reagent liquid is significantly larger than the flow rate of the sample liquid, most of the sample liquid at the merging point is eliminated before and after the merging point, and apparently approaches the state of FIG. it is conceivable that.

That is, the present inventors provide, as a first invention, a tubular main flow path through which a sample liquid flows, a sample liquid supply means for flowing the sample liquid through the main flow path, and a reagent liquid injection which joins in the middle of the main flow path. Means, and a detector which is located downstream of a position where the reagent liquid injecting means of the main flow path joins and detects a reaction between the sample liquid and the reagent liquid, wherein the reagent liquid injecting means includes a reagent in the main flow path. Provided is a flow analyzer characterized by intermittently joining liquids. According to this apparatus, since the reagent liquid is merged with the sample liquid, the reagent liquid can be injected without providing a switching valve or the like on the main flow path, and is less affected by suspended substances and the like.

In the present invention, the reagent liquids may be intermittently merged not only at one position on the main flow path but also at a plurality of positions. In this case, the injection is performed at a timing such that the reagent solutions merge with each other so that the individually injected reagents react with the same portion of the sample solution. Thereby, analysis using a plurality of reagent solutions is possible.

The reagent injecting means comprises a chemical solution pump, a conduit from the chemical solution pump to the main flow path, a connecting pipe provided at a junction of the conduit and the main flow path, and the like. Of these, a pump capable of intermittently sending liquid, such as a syringe pump or a piezo pump, is desirable as the chemical liquid pump. In this case, only the necessary amount of the chemical solution is injected, and the pump can be stopped except at the time of injection, so that the consumption amount of the reagent solution can be suppressed to only the injection amount. In particular, when a syringe pump is used, the reagent solution can be introduced in a very short cycle, and it is easy to increase the number of data acquisitions per unit time.

As a second invention, the present inventors intermittently join a reagent solution to a sample solution flowing through a tubular flow path, and detect a reaction between the sample solution and the reagent solution after the joining, so that the A flow analysis method characterized by analyzing a target component of the flow analysis. According to this method, since the reagent liquid is merged with the sample liquid, the reagent liquid can be injected without providing a switching valve or the like on the main flow path, and is less susceptible to floating substances and the like.

In the present invention, the reagent liquids may be intermittently joined not only at one position on the main flow path but also at a plurality of positions. In this case, the injection is performed at a timing such that the reagent solutions merge with each other so that the individually injected reagents react with the same portion of the sample solution. Thus, analysis using a plurality of reagent solutions is possible.

The present inventors also have a specific analysis method in which 2,4,6-tri-2
Analyzing the iron component in the sample solution by intermittently joining the pyridyl-1,3,5-triazine reagent solutions and detecting the reaction between the sample solution and the reagent solution with the absorption detector after the merging; And a method for analyzing iron. With this analysis method, divalent iron can be measured.

Further, a reducing agent for reducing trivalent iron to divalent iron as a first reagent solution is intermittently joined to the sample solution flowing through the tubular flow path, and a second reagent is provided downstream of the reducing agent. As a reagent solution, 2,4,6-tri-2-pyridyl-1,
The 3,5-triazine reagent solution is intermittently merged so as to merge with the first reagent solution, and after the merge, the reaction between the sample solution and the first and second reagent solutions is detected by an absorption detector. And a method for analyzing an iron component characterized by analyzing an iron component in a sample solution. In this analysis method, the total amount of divalent and trivalent iron can be measured.

Further, the sample liquid flowing through the tubular flow path is added to the first liquid.
And a hydrochloric acid solution of sulfanilamide is intermittently joined as a reagent solution, and an N-1-naphthylethylenediamine solution is added as a second reagent solution at the downstream side of the solution.
Nitric acid in the sample liquid is analyzed by intermittently merging with the reagent liquid of the sample liquid and detecting the reaction between the sample liquid and the first and second reagent liquids with an absorption detector after the merge. A method for analyzing nitrous acid is provided.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 3 shows an embodiment of the analyzer according to the present invention. In FIG. 3, a pump 12 such as a peristaltic pump or the like is interposed in the tubular main flow path 11 through which the sample liquid flows as a sample liquid sending means. The suction end of the pump 12 is inserted into the sample liquid tank 13. The discharge-side tip of the syringe pump 14 constituting the reagent liquid injecting unit merges with the main flow channel 11 at the merging position 15. The suction end of the syringe pump 14 is inserted into the reagent solution tank 16. Further, a detector 17 for detecting a reaction between the sample liquid and the reagent liquid is provided downstream of the merging position 15 of the main flow path 11.

A switching valve such as a slide valve, a check valve, or the like is provided so that the reagent solution is sucked from the reagent solution tank 16 side when the syringe pump 14 is sucked, and the reagent solution is ejected toward the confluence point 15 when the syringe pump 14 is ejected. Is used as appropriate to control the liquid sending direction. In addition, the syringe pump 14
Is configured to aspirate a large amount of reagent solution from the reagent solution tank 16 at a time, and then sequentially discharge the required amount of reagent solution for one injection using a stepping motor or the like. Then, when all of the reagent solution inside is discharged, the operation from suction is repeated again.

In the present analyzer, the pump 12 is operated to continuously flow the sample liquid through the main channel 11. Then, the syringe pump 14 is operated intermittently to discharge the reagent liquid intermittently and to merge with the sample liquid. Then, the main flow path 11
Reacts while diffusing and mixing with the surrounding sample solution. Then, by detecting this reaction product with the detector 17, the target component in the sample liquid can be analyzed.

As described above, since the reagent liquid is injected by merging, it is not necessary to arrange a switching member such as a six-way valve in the main flow path 11 through which the sample liquid flows. Therefore, even if the sample liquid contains suspended particulate matter or the like, there is no concern that this may cause the switching member to fail. In addition, since the syringe pump can perform liquid supply intermittently, the liquid supply of the reagent can be stopped except at the time of injection, and the consumption of the reagent can be suppressed to only the amount necessary for the reaction with the sample liquid. . Furthermore, syringe pumps are much cheaper than six-way valves, which can reduce the overall cost of the device.

FIG. 4 shows another embodiment of the analyzer according to the present invention. In FIG. 4, a pump 22 such as a peristaltic pump is interposed as a sample liquid sending means in the tubular main channel 21 through which the sample liquid flows. The suction end of the pump 22 is inserted into the sample liquid tank 23. Further, the discharge-side distal ends of the syringe pumps 24a and 24b constituting the reagent liquid injection means merge with the main flow path 21 at the merging positions 25a and 25b, respectively. The suction ends of the syringe pumps 24a and 24b are inserted into the reagent solution tanks 26a and 26b, respectively. Further, a detector 27 for detecting a reaction between the sample liquid and the reagent liquid is provided further downstream of the merging positions 25a and 25b of the main flow path 21.

The direction of liquid supply by the syringe pump 24 is controlled by a check valve or the like, similarly to the syringe pump 14 described above. Further, the syringe pump 24 also performs a collective amount of suction operation and an intermittent discharge operation similarly to the syringe pump 14 described above.

In the present analyzer, the pump 22 is operated to continuously flow the sample liquid through the main channel 21. Then, the syringe pumps 24a and 24b are intermittently operated to intermittently discharge the respective reagent liquids and merge with the sample liquid. The syringe pump 24b is connected to the reagent solution from the reagent solution tank 26a joined by the syringe pump 24a and the reagent solution tank 2
It is operated at a timing at which the reagent solution from 6b can merge with each other. Then, the reagent liquid from the reagent liquid tank 26a that has merged into the main flow path 21 reacts while diffusing and mixing with the surrounding sample liquid, and reacts with the reaction product from the reagent liquid from the reagent liquid tank 26b that has merged later. React while diffusing and mixing.
Then, by detecting the final reaction product with the detector 27, the target component in the sample liquid can be analyzed.

As described above, the injection of the reagent solution by merging can be performed at a plurality of locations on the main flow path. Therefore, even when an analysis method utilizing a multi-stage reaction using a plurality of reagent solutions is adopted, An analyzer that utilizes the advantages of the embodiment shown in FIG. 3 can be configured.

FIG. 5 also shows another embodiment of the analyzer according to the present invention. In FIG. 5, a pump 32 such as a peristaltic pump is interposed as a sample liquid sending means in a tubular main flow path 31 through which a sample liquid flows. The suction end of the pump 32 is inserted into the sample liquid tank 33. Further, the tip on the discharge side of the syringe pump 34 that constitutes the reagent liquid injection means,
At the merging position 35, it merges with the main flow path 31. The suction end of the syringe pump 34 is inserted into the reagent solution tank 36. Further, the analyzer according to the present embodiment includes pumps 41 and 42 such as a peristaltic pump for continuously injecting a reagent solution. The discharge-side tips of the pumps 41 and 42 are connected to the upstream position 43 and the downstream position 4 of the merging position 35.
At 4, each of them merges with the main channel 31. The suction ends of the pumps 41 and 42 are inserted into reagent solution tanks 45 and 46, respectively. Further, a detector 37 for detecting a reaction between the sample liquid and the reagent liquid is provided further downstream of the merging position 44 of the main flow path 31.

The direction of liquid supply by the syringe pump 34 is also controlled by a check valve or the like, similarly to the syringe pump 14 described above. Further, the syringe pump 34 also performs a large amount of suction operation and an intermittent discharge operation similarly to the syringe pump 14 described above. The pumps 32, 4
1, 42 are shown as separate pump devices,
Of course, it may be configured as a single peristaltic pump capable of handling a plurality of liquid feeds.

In this analyzer, the pump 32 is operated to continuously flow the sample liquid into the main flow path 31 and the pump 41
Is also operated continuously to continuously join the reagent liquid in the reagent liquid tank 45 with the sample liquid. And the syringe pump 3
4 is operated intermittently so that the reagent liquid in the reagent liquid tank 36 is intermittently discharged to join the mixed liquid of the sample liquid and the reagent liquid in the reagent liquid tank 45. Further, the pump 42 is also continuously operated to continuously join the reagent solution in the reagent solution tank 46 with the mixed fluid of the sample solution and the reagent solutions in the reagent solution tanks 45 and 36. By detecting the final reaction product obtained as a result with the detector 37, the target component in the sample liquid can be analyzed.

As described above, the apparatus can be configured by appropriately combining the continuous injection of the reagent solution with the injection of the reagent solution by intermittent merging, so that the reaction using a plurality of reagent solutions is utilized. Various analysis methods can be adopted. Also in this case, the expensive reagent solution can be intermittently sent using the syringe pump 34, and an analyzer that utilizes the various advantages described in the embodiment shown in FIG. 3 is configured. be able to. Reagents suitable for continuous injection include reagents that need to be added to the entire sample, such as a pH adjuster for ensuring the stability of the sample, and inexpensive reagents. A reagent solution or the like is conceivable.

[0031]

FIG. 6 shows a TPTZ as an embodiment of the present invention.
1 shows an iron analysis device by the method. In FIG. 6, a peristaltic pump 52 is interposed as a sample liquid sending means in a tubular main flow path 51 through which a sample liquid flows. Peristaltic pump 52
Is inserted into the sample liquid tank 53. Also,
The discharge-side tip of the syringe pump 54 constituting the reagent liquid injection unit merges with the main flow path 51 at a merge position 55. The suction end of the syringe pump 54 is inserted into the reagent solution tank 56. Further, a detector 57 for detecting a reaction between the sample liquid and the reagent liquid is provided downstream of the merging position 55 of the main flow path 51. Further, a deaerator 58 is provided upstream of the merging position 55 of the main flow path 51,
A reaction coil 59 is interposed between the sensor 57 and the detector 57. Note that the deaerator 58 may be disposed upstream of the peristaltic pump 52.

As a comparative example, FIG. 7 shows a conventional iron analyzer based on the TPTZ method. 7, the same components as those in FIG. 6 are denoted by the same reference numerals as those in FIG. 6, and description thereof will be omitted. In this comparative example, a six-way valve 61 is provided instead of the peristaltic pump 52.
The six-way valve 61 operates as described with reference to FIGS. 16 and 17, and replaces a part of the sample liquid in the main flow path 51 with a reagent liquid.

FIGS. 8 and 9 show the results of measurement using the apparatus shown in FIGS. 6 and 7, respectively. The specific conditions for the measurement are as follows. Sample solution: Fe · HNO ₃ (metal iron dissolved in nitric acid, iron concentration 1000 μg / L) Reagent solution: 2,4,6-tri-2-pyridyl-1,3,5
-Triazine (0.16 g / L) Sample solution flow rate by pump 52: 1 mL / min Reagent solution injection amount: 100 μL Reagent solution injection speed (for FIG. 8): 100 μL / 0.8
Second main flow path 51: made of polyetheretherketone, inner diameter 0.
5 mm reaction coil 57: made of polyetheretherketone, inner diameter 0.5 mm, length 3.2 m Detector: visible absorption detector 595 nm

As shown in FIGS. 8 and 9, in the case of the present embodiment, the same measurement results as in the case of the prior art were obtained. Here, FIG. 8 and FIG. 9 are data obtained by one injection of the reagent solution, and two separated peaks are obtained. This is presumably because both ends of the injected reagent solution can react while mixing with the sample solution before and after the injection point, but the central portion of the reagent solution lacks the sample solution to be reacted.

In order to confirm this presumption, an experiment was conducted under the following conditions by lowering the pH of the sample solution. The results are shown in FIGS. Sample solution: 0.01 mol / L HCl solution (iron concentration 1000) of Fe.HNO ₃ (metal iron dissolved in nitric acid)
μg / L) Reagent solution: 2,4,6-tri-2-pyridyl-1,3,5
-Triazine (0.16 g / L) Sample solution flow rate by pump 52: 1 mL / min Reagent solution injection amount: 100 μL Reagent solution injection speed (for FIG. 10): 100 μL / 0.
8 seconds Main flow path 51: Made of polyetheretherketone, inner diameter of 0.1
5 mm reaction coil 57: made of polyetheretherketone, inner diameter 0.5 mm, length 2.2 m Detector: visible absorption detector 595 nm

As shown in FIGS. 10 and 11, a substantially single peak is obtained by one injection of each reagent solution.
This means that at both ends of the injected reagent solution, it reacts while mixing with the sample solution before and after the injection point, but the pH concentration of the sample solution is too low and the reaction slows down. It is considered that the reaction proceeded smoothly because the solution was diluted and the pH concentration became near neutrality. Also in the cases shown in FIGS. 10 and 11, equivalent measurement results were obtained in the case of the present embodiment and in the case of the conventional technique.

Next, FIG. 12 and FIG. 13 show the results of measurement using the apparatus of FIG. 6 using sample solutions having different iron concentrations. The specific measurement conditions are the same as those in FIG. 8 except that the iron concentration was changed. FIG. 12 shows that 1000 μg /
L, data during the five injections of the reagent solution into the 500 μg / L sample solution, and two samples of the reagent solution in the 0 μg / L sample solution.
The data during the single injection is shown. FIG. 13 shows two peaks obtained by one injection of the reagent solution.
The calibration curve created based on the previously observed peak is shown. As shown in FIGS. 12 and 13, good data was obtained in both reproducibility and linearity.

The iron analyzer shown in FIG. 6 can measure only divalent iron. If the total concentration of divalent and trivalent iron is to be measured, a reducing agent is introduced into the sample solution in advance,
What is necessary is just to reduce trivalent iron to divalent. Specifically, as described in FIG. 4, the first reagent is a reducing agent, and the second reagent is 2,4,6-tri-2-pyridyl-
It is desirable to use a method in which a 1,3,5-triazine solution is intermittently joined to a sample solution at a suitable timing so that each reagent joins each other. According to this, the amount of the reducing agent used can be minimized. Further, as described in FIG. 5, the reducing agent is continuously combined with the sample solution by a peristaltic pump or the like, and then the 2,4,6-tri-2-pyridyl-1,3,5-triazine solution is intermittently added. It is also possible to join them. As the reducing agent, a hydroxylammonium chloride solution can be suitably used, but it is not particularly limited thereto.

FIG. 14 shows a nitrite analyzer as another embodiment of the present invention. In FIG. 14, a peristaltic pump 72 is provided as a sample liquid sending means in a tubular main channel 71 through which a sample liquid flows. The suction end of the peristaltic pump 72 is inserted into the sample liquid tank 73. The discharge-side tips of the syringe pumps 75a and 75b constituting the reagent liquid injection means are connected to the main flow path 71 at the merging positions 75a and 75b.
Has joined. Also, the syringe pumps 74a, 74b
Are inserted into the reagent solution tanks 76a and 76b, respectively. Also, the merging positions 75a and 75b of the main flow path 71
A detector 77 for detecting a reaction between the sample liquid and the reagent liquid is provided downstream of any one of the above. Further, a deaerator 78 is provided upstream of the merging position 75a of the main flow path 71, and a reaction coil 79 is interposed between the merging position 75a and the merging position 75b. Note that the deaerator 78 may be arranged on the upstream side of the peristaltic pump 72.

FIG. 1 shows the result of measurement using the apparatus shown in FIG.
It is shown in FIG. The specific conditions for the measurement are as follows. Sample solution: nitrous acid aqueous solution (500 μg / L, 100 μg / L
L, 0 μg / L) Reagent solution (reagent solution tank 76a): sulfanilamide 1
0.0 g, hydrochloric acid 10 mL, and purified water made up to 500 mL Reagent solution (reagent solution tank 76b): N-1-naphthylethylenediamine aqueous solution (20 g / L) Sample solution flow rate by pump 72: 1 mL / min Reagent solution injection Volume: 50 μL Reagent solution injection rate: 50 μL / 0.4 second Main flow path 71: made of polyetheretherketone, inner diameter of 0.1 μm
5 mm reaction coil 77: made of polyetheretherketone, inner diameter 0.5 mm, length 3.2 m Detector: visible absorption detector 540 nm

As shown in FIG. 15, also in the case of the present embodiment, a good correlation was obtained between the sample solution concentration and the absorbance.

[0042]

According to the present invention, even if the sample liquid contains suspended particulate matter, the flow path of the sample liquid does not include a flow path switching member having a rubbed portion. There is no fear that the liquid will enter the rubbed portion and cause damage and cause liquid leakage or the like. In addition, since it is not necessary to use expensive parts such as a six-way valve, the apparatus can be configured at low cost.

Further, if a syringe pump is used as the reagent liquid injecting means, it is sufficient to use only the amount of the reagent liquid that actually reacts with the sample liquid, and the consumption can be minimized. Therefore, it is suitable for long-time continuous operation such as water quality monitoring.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of the present invention.

FIG. 2 is an explanatory diagram of a conventional technique.

FIG. 3 is a configuration diagram showing one embodiment of an analyzer according to the present invention.

FIG. 4 is a configuration diagram showing another embodiment of the analyzer according to the present invention.

FIG. 5 is a configuration diagram showing another embodiment of the analyzer according to the present invention.

FIG. 6 is a configuration diagram showing one embodiment of an analyzer according to the present invention.

FIG. 7 is a configuration diagram showing an analysis device according to a conventional technique as a comparative example.

FIG. 8 shows the results of measurement using the apparatus of FIG.

FIG. 9 shows the results of measurement using the apparatus of FIG.

FIG. 10 shows the result of measurement using the apparatus of FIG.

FIG. 11 shows the result of measurement using the apparatus of FIG.

FIG. 12 shows the results of measurement using the apparatus of FIG.

FIG. 13 shows the results of measurement using the apparatus of FIG.

FIG. 14 is a configuration diagram showing another embodiment of the analyzer according to the present invention.

FIG. 15 shows the results of measurement using the apparatus of FIG.

FIG. 16 is an explanatory diagram of a six-way valve.

FIG. 17 is an explanatory diagram of a six-way valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main flow path 2 Sample liquid 3 Reagent liquid 13 Sample liquid layer 14 Syringe pump 15 Merging position 16 Reagent liquid tank 17 Detector

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G01N 33/18 G01N 33/18 C F term (Reference) 2G042 AA01 BB08 BC08 CA02 CB03 DA10 FA05 FA20 FB02 2G054 AA02 CA10 CE01 EA04 FA08 2G058 AA01 DA01 DA02 EB01 GA02 GA06

Claims (8)

[Claims] 1. A tubular main flow path through which a sample liquid flows, a sample liquid feeding means for flowing a sample liquid into the main flow path, a reagent liquid injection means joining in the middle of the main flow path, and a reagent liquid injection means in the main flow path. A detector for detecting a reaction between the sample liquid and the reagent liquid that is present downstream from the merging position, and the reagent liquid injecting means includes:
A flow analyzer wherein a reagent solution is intermittently joined to a main flow path. 2. A tubular main flow path through which a sample liquid flows, a sample liquid sending means for flowing a sample liquid into the main flow path, two or more reagent liquid injection means joining at different positions in the middle of the main flow path, and a main flow path A detector that is located further downstream than any position where each of the reagent liquid injecting means merges and detects a reaction between the sample liquid and the reagent liquid. A flow analyzer wherein a reagent solution is intermittently merged with another reagent solution so as to merge with each other. 3. The flow analyzer according to claim 1, wherein the reagent liquid injecting means includes a syringe pump. 4. A method of analyzing a target component in a sample liquid by intermittently joining a reagent liquid to a sample liquid flowing through a tubular flow path and detecting a reaction between the sample liquid and the reagent liquid after the merging. And flow analysis method. 5. A sample liquid flowing in a tubular flow path, wherein two or more reagent liquids are intermittently joined at different positions in the tubular flow path so that each reagent liquid and another reagent liquid merge with each other. A flow analysis method comprising: analyzing a target component in a sample solution by detecting a reaction between the sample solution and the reagent solution after all the reagent solutions have joined. 6. A sample solution flowing through a tubular flow path,
-The tri-2-pyridyl-1,3,5-triazine reagent solution is intermittently joined, and after the joining, the reaction between the sample solution and the reagent solution is detected by an absorption detector, whereby the iron component in the sample solution is detected. A method for analyzing iron, comprising: analyzing iron. 7. A reducing agent for reducing trivalent iron to divalent iron as a first reagent solution is intermittently joined to a sample solution flowing through the tubular flow path, and a second reagent is provided downstream of the reducing agent. 2,4,6-tri-2-pyridyl-1,3,5 as a reagent solution
-The triazine reagent solution is intermittently merged so as to merge with the first reagent solution, and after the merge, the reaction between the sample solution and the first and second reagent solutions is detected by an absorption detector, whereby the sample solution is An iron analysis method characterized by analyzing iron components in the iron. 8. A sulfonylamide hydrochloric acid solution as a first reagent solution is intermittently joined to a sample solution flowing through a tubular flow channel, and N-1-naphthylethylenediamine is used as a second reagent solution at a downstream side thereof. The solution is intermittently merged so as to merge with the first reagent solution, and after the merge, the reaction between the sample solution and the first and second reagent solutions is detected by an absorption detector, whereby the sub-solution in the sample solution is detected. A nitrite analysis method characterized by analyzing nitric acid.