Measurement system and method for measuring ion concentration in a processing liquid using capillary electrophoresis

Abstract

The present invention relates to a measurement system for measuring the ion concentration in a processing liquid using capillary electrophoresis, the measurement system comprising: a supply line extending between a first end and a second end, the supply line having a flow direction from the first end to the second end; an inlet connected to the supply line at the first end; a pump provided in the supply line; an expansion vessel connected to the supply line by an expansion line, the expansion line being provided with a first valve; and a capillary electrophoresis measurement device connected to the supply line at the second end, wherein the pump, the first valve, and the expansion vessel cooperate to accumulate and release pressure for loading a sample into the capillary electrophoresis measurement device.

Description

Technical Field

[0001] The present invention relates to a measurement system for measuring the ion concentration in a processing liquid using capillary electrophoresis. The present invention further relates to a method for measuring the ion concentration in a processing liquid using capillary electrophoresis. Such processing liquids relate, inter alia, to water treatment, beverage production, (lawn) gardening, fermentation, food processing, pharmaceutical processing, and industrial process flows. The ion concentration can include both organic and inorganic ions.

Background Art

[0002] Capillary electrophoresis, also called CE, is an analytical separation technique. An electric field is applied to a capillary such that a sample loaded into the capillary flows through the capillary and is separated. This separation is caused by differences in the electrophoretic mobilities of the particles from the sample. Among other factors, all of the charge and dimensions of the particles can affect the differences in the electrophoretic mobilities of the particles.

[0003] Measurement systems using capillary electrophoresis are known. Known measurement systems change the capillary from a buffer container to a sample liquid container in order to load the sample liquid. This requires, for example, a pressure of 2 bar to fill the capillary with the processing fluid. The container to which the processing liquid is supplied also receives the pressure for filling the capillary in order to fill the capillary with the processing liquid.

[0004] A disadvantage of known measurement systems is that the walls of the container containing the processing liquid need to be relatively thick in order to withstand the pressure. As a result, the container is expensive. A further disadvantage is that filling the capillary with the processing liquid is not very reproducible because the pressure obtained by applying pressure to the container containing the processing liquid can vary.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The object of the present invention is to prevent or at least reduce the above-mentioned problems. In particular, the object of the present invention is to provide a measurement system for obtaining a reproducible amount of a processing liquid filled in a capillary.

Means for Solving the Problems

[0006] This object is achieved by a measurement system for measuring the ion concentration in a processing liquid using capillary electrophoresis, the measurement system comprising: - A supply line extending between a first end and a second end, the supply line having a flow direction from the first end to the second end; - An inlet connected to the supply line at the first end; - A pump provided in the supply line; - An expansion vessel connected to the supply line by an expansion line, the expansion line being provided with a first valve; - A capillary electrophoresis measurement device connected to the supply line at the second end and the pump, the first valve, and the expansion vessel cooperate to accumulate and release pressure for loading a sample into the capillary electrophoresis measurement device.

[0007] Due to the cooperation of the pump, the first valve, and the expansion vessel to accumulate and release pressure, a self-contained system for automatically injecting a sample into the capillary electrophoresis measurement device is obtained. The advantage is that the sample can be effectively loaded into the capillary electrophoresis measurement device. For example, the pump can be controlled by a controller to automatically inject the sample into the capillary. This has the advantage that the sample solution can be automatically supplied to the capillary. It is obvious that other solutions such as buffer solutions can also be automatically injected into the capillary electrophoresis measurement device in this way.

[0008] A further advantage of the present invention is that all elements provided in front of the inlet can be maintained under atmospheric pressure. This has the advantage that the containers (or vessels) for the sample solution and the buffer solution that can be connected to the inlet do not need to withstand pressures higher than atmospheric pressure and can thus be relatively inexpensive. The high pressure accumulates mostly in the supply line, within the measurement system itself.

[0009] An expansion vessel can achieve an effective accumulation of the same amount of pressure. The pump is configured to pump the processing liquid into the expansion vessel when the first valve is open, thereby increasing the pressure of the processing liquid in the expansion vessel. Further, the expansion vessel can effect an effective release of the pressurized processing liquid, and through the pressurized processing liquid, the sample solution or the buffer solution can be effectively conveyed through the measurement system. An additional advantage of this configuration with an expansion vessel is that the measurement system can be substantially smaller as a whole. This reduces the amount of storage space and the amount of reagents required for the measurement system, and thus reduces its cost during use.

[0010] It should be noted that the expansion vessel in the context of the present invention is to be understood as a device configured to achieve pressure accumulation. For example, a supply line including an internal throughput line and an external tube coaxially provided on the supply line, where the space between the supply line and the external tube is configured to receive compressed air so that the supply line is closed to accumulate pressure during the operation of the pump, can also be understood as an expansion vessel. Operating the pump may be understood as operating or starting the pump, meaning that the pump is in an active pumping state.

[0011] Subsequently, the switching and / or replacement of the sample solution to be measured is simplified. Alternatively or additionally, the maintenance of the measurement system is also easy.

[0012] The processing liquid can be, inter alia, a sample liquid, a buffer solution, or a cleaning solution. In the context of the present invention, the reagent can mean a buffer solution, a cleaning solution, and a calibration solution. The buffer solution can be an anion buffer solution or a cation buffer solution. For example, the supply line can be embodied as a tube, a channel, or a pipe, or any other element suitable for liquid throughput. The capillary electrophoresis measurement device preferably includes at least one capillary. The cleaning solution can be a base such as a sodium hydroxide (NaOH) solution, an acid such as hydrochloric acid (HCl), or ultrapure water.

[0013] In one embodiment according to the present invention, the supply line includes a second valve located between the pump and the second end of the supply line.

[0014] By means of the second valve, the pressure that can be accumulated in the expansion vessel can be selectively released towards the capillary electrophoresis measurement device. In practice, the second valve is closed while the pressure is being accumulated and opened after the pressure has been accumulated to release the pressurized processing liquid into the capillary electrophoresis measurement device. By opening the second valve for a controlled time, preferably a predetermined time, the sample liquid and other processing liquids can be controlled in a reproducible manner.

[0015] In one embodiment according to the present invention, the capillary electrophoresis measurement device includes a first capillary and a second capillary, the first capillary being an anion capillary and the second capillary being a cation capillary.

[0016] The advantage of the first capillary and the second capillary is that both anion ions and cation ions can be effectively measured in the sample liquid. This enhances the usefulness of the measurement system according to the present invention.

[0017] In one embodiment according to the present invention, the capillary electrophoresis measurement device is connected to a three-way valve that connects the second end of the supply line to the first capillary and the second capillary, and preferably both the first capillary and the second capillary are in contact with the associated buffer solution waste container.

[0018] The three-way valve includes three passages. The first passage is operably connected to the supply line, the second passage is operably connected to the first capillary, and the third passage is connected to the second capillary. By the three-way valve, the processing liquid can be effectively conveyed from the supply line to the first capillary and the second capillary.

[0019] In one embodiment according to the present invention, the three-way valve and the first capillary and the second capillary are each connected to a respective T-piece.

[0020] By the T-piece, the pressurized processing liquid can be effectively inserted into the capillary electrophoresis measurement device.

[0021] Alternatively, the first capillary and the second capillary are connected to each other to form a single capillary, and the sample solution is inserted into the center of the single capillary.

[0022] In one embodiment according to the present invention, the measurement system further includes an expansion container, a supply line, and / or a waste container operably connected to the capillary electrophoresis measurement device.

[0023] The advantage of the waste container is that the processing liquid can be effectively collected in the waste container. By the expansion container, the supply line and / or the capillary electrophoresis measurement device are operably connected to the waste container, and the processing fluid can be throughput from each of these elements to the waste container.

[0024] In one embodiment according to the present invention, each of the expansion vessel, the supply line, and the capillary electrophoresis measurement device is operably connected to a waste container by respective lines, and each line is provided with a valve.

[0025] In the context of the present invention, the valve from the expansion vessel to the waste container is shown as the third valve, the valve from the supply line between the second valve and the capillary electrophoresis measurement device to the waste container is shown as the fourth valve, and the valve from the capillary electrophoresis measurement device to the waste container is shown as the fifth valve.

[0026] By the third, fourth, and fifth valves, the processing liquid can be selectively allowed to flow towards the waste container.

[0027] In one embodiment according to the present invention, the system further includes a pressure sensor connected to the expansion vessel.

[0028] The advantage of the pressure sensor is that the pressure in the processing liquid can be easily read and controlled. The pump can be configured to stop operating when a predetermined pressure is reached. After reaching this predetermined pressure, the second valve can be opened for a predetermined time period. This achieves that the amount of the processing liquid can be effectively controlled together with the amount of the processing liquid inserted into the capillary electrophoresis measurement device. This ensures that reliable measurements are achieved. Preferably, the pressure sensor includes a pressure gauge.

[0029] In one embodiment according to the present invention, the capillary electrophoresis measurement device includes a voltage circuit provided on the capillary.

[0030] By the voltage circuit, a voltage is applied to the capillary, and it can separate the ions in the sample liquid based on the electrophoretic mobility of the ions.

[0031] In one embodiment according to the present invention, the capillary electrophoresis measurement device includes a non-contact conductivity detector.

[0032] A non-contact conductivity sensor can effectively detect the conductivity of a sample solution and thus can detect ions moving through a capillary. Alternatively or additionally, a capillary electrophoresis measurement device includes other detectors such as an ultraviolet sensor or a mass spectrometry detector.

[0033] In one embodiment according to the present invention, the inlet includes a multi-valve.

[0034] The advantage of the multi-valve is that a plurality of containers or vessels can be connected to the multi-valve. For example, the multi-valve can be connected to an anion buffer solution, a cation buffer solution, and a sample solution. In this way, the multi-valve can supply all the necessary liquids to obtain capillary electrophoresis measurement results.

[0035] In one embodiment according to the present invention, the multi-valve is connected to a second buffer solution container and a solution inlet such that a buffer solution and a sample solution can be supplied into the supply line.

[0036] The second buffer solution can be an anion buffer solution or a cation buffer solution. In one embodiment, the multi-valve is connected to both an anion buffer solution container and a cation buffer solution container. Due to the multi-valve being connected to the second buffer solution container and the sample solution inlet, the buffer solution and the sample can be inserted into the measurement system for cleaning the system or filling the capillary electrophoresis measurement device with the buffer solution or the sample solution.

[0037] In one embodiment according to the present invention, the measurement system further includes a loading module including a buffer solution and / or a cleaning solution operably connected to the inlet.

[0038] By means of a loading module, the liquid necessary for performing capillary electrophoresis measurement is supplied by connecting the loading module to an inlet. In this way, even a person without experience in performing capillary electrophoresis measurement can easily replace the processing liquid. In addition, the loading module can be easily disconnected in order to connect a further loading module, for example when the containers to which a buffer solution and a cleaning solution are supplied are empty.

[0039] Alternatively or additionally, the loading module contains a calibration solution. The calibration solution is a known solution containing a concentration of a predetermined ion. The calibration solution can be loaded as a sample onto a capillary electrophoresis measurement device in order to calibrate the sensor of the measurement device or to indicate that the sensor is operating correctly.

[0040] In one embodiment, the measurement system includes a dilution controller operably connected to and configured to control at least one of an inlet, a pump, a first valve, a second valve, a third valve, a fourth valve, and / or a fifth valve. The controller can be configured to connect the inlet to a specific processing liquid. The controller can be set to operate the pump or to stop the pump. The controller can be set to close the valve or to open the valve.

[0041] Alternatively or in addition, the controller may be configured to dynamically dilute the sample solution, preferably with ultrapure water. In this embodiment, the measurement system preferably further includes an ultrapure water container connected to a multi-valve. Optionally, the measurement system includes a mixing device configured to mix the sample solution and ultrapure water to dilute the sample solution. The amount of dilution can be determined in advance. Alternatively, in one embodiment that enables dynamic dilution of the sample solution, the amount of dilution may be determined by a prior measurement of the sample solution, thereby achieving dynamic dilution of the sample solution. This ensures the success of the measurement of the sample solution. For example, the dilution controller may determine during measurement that the peak of the measured ion concentration is higher than a predetermined value, thereby determining that the ion concentration is too high. The dilution controller may then set the mixing device to increase the amount of dilution to lower the peak of the ion concentration below the predetermined value. This is an example of dynamically diluting the sample solution. In another example, when the detection is relatively sensitive, a small amount of ions may be measured. When a higher concentration is available, the sample needs to be diluted towards a measurable amount. To enable handling of such situations, in one of the presently preferred embodiments, the measurement system includes a dynamically (adaptively) diluting, preferably automated dilution setup for the sample. In such an embodiment, the first input is the sample source and the expected concentration (or overall conductivity). This is a predetermined input that ensures a predetermined limit. The second input is a built-in conductivity sensor. This provides additional information about the total sample and its dilution level. The dilution controller determines whether the expected concentration matches the set limit from the first input. If they match, the dilution ratio remains the same. If they do not match, the dilution ratio is changed. The third input is the actual measurement result. If the peak in the electrophoretogram exceeds the maximum set value, the dilution controller calculates a new dilution suitable for effective measurement using the measurement system. The dilution controller may be a separate controller or integrated within the controller of the measurement system.Optionally, the dilution is preferably carried out in a diluter comprising a mixing tank and a mixing device.

[0042] In one embodiment, the measurement system includes a temperature control device configured to globally regulate the temperature of the measurement system. The temperature control device may include a heat insulating material and / or an (air) cooling system.

[0043] The present invention further relates to a water measurement system, such as a horticultural water measurement system, the water measurement system comprising - a measurement system according to any one of the foregoing embodiments, and - a water system operably connected to an inlet for supplying a sample solution and including.

[0044] The water measurement system has the same effects and advantages as those described for the measurement system. In particular, the water measurement system offers the possibility of continuously and automatically monitoring, for example, the water system of a horticultural water measurement system. This is particularly advantageous since the ion level in the water can vary significantly over the course of a day and / or a week due to the influence of weather conditions, such as the amount of sunlight. Therefore, it is advantageous that the ion level in the water of a horticultural water system can be measured continuously. By continuous in the present invention is meant not only continuous measurement without interruption, but also measurement at regular intervals, which intervals are relatively short, such as every 5 minutes or every half hour, as will be understood by those skilled in the art.

[0045] The present invention further relates to a method for measuring the ion concentration in a processing solution using capillary electrophoresis, the method comprising - filling the supply line and the capillary electrophoresis measurement device with a buffer solution by using an expansion vessel; and - filling the supply line and the capillary electrophoresis measurement device with a sample solution by using an expansion vessel. - applying a high voltage to the capillary to measure the sample solution using a detector of the capillary electrophoresis measurement device comprises.

[0046] The method has the same effects and advantages as those described for the measurement system and the water measurement system. Preferably, the method includes providing a measurement system according to any one of the embodiments described above of the present invention.

[0047] In one embodiment according to the present invention, the step of filling the supply line and the capillary electrophoresis measurement device with the buffer solution is - supplying the buffer solution through an inlet at a first end of the supply line and opening a second valve located on the supply line towards the capillary electrophoresis measurement device located at a second end of the supply line to fill the supply line with the buffer solution; - operating a pump located on the supply line between the inlet and the second valve and opening the first valve towards the expansion vessel and closing the second valve to increase the pressure of the buffer solution in the supply line; - opening the second valve to release the pressurized buffer solution towards the capillary electrophoresis measurement device to fill the capillary with the buffer solution comprises.

[0048] By increasing the pressure of the buffer solution, the buffer solution can be effectively loaded into the capillary electrophoresis measurement device.

[0049] In one embodiment according to the present invention, the step of filling the supply line and the capillary electrophoresis measurement device with the sample solution is - supplying the sample solution through the inlet and opening the second valve to fill the supply line with the sample solution; - operating the pump, opening the first valve towards the expansion vessel and closing the second valve to increase the pressure of the sample solution in the supply line; - By opening the second valve, releasing the pressurized sample solution towards the capillary electrophoresis measurement device, and loading the sample solution into the capillary. including.

[0050] The second valve can be opened for a predetermined time period. Due to increasing the pressure of the sample solution and the controlled opening time of the second valve, the sample solution can be effectively loaded into the capillary electrophoresis measurement device. Alternatively or additionally, accumulating pressure using an expansion vessel ensures that a controllable and reproducible pressurized solution is obtained, and thus the same amount of sample solution can be inserted into the capillary of the capillary electrophoresis measurement device. This is further improved by the volume of the processing or sample solution generated in the expansion vessel while the pressure is being accumulated.

[0051] In one embodiment, the sample solution is diluted before being supplied to the inlet. The sample solution can be diluted by adding ultrapure water to the sample solution. The amount of dilution can be determined in advance. Alternatively, the amount of dilution may be determined by a prior measurement of the sample solution, thereby achieving dynamic dilution of the sample solution. This ensures the success of the measurement of the sample solution. For example, during the measurement, it can be determined that the peak of the measured ion concentration is higher than a predetermined value, thereby determining that the ion concentration is too high. In response, the amount of dilution can be increased to lower the peak of the ion concentration below the predetermined value. Dilution is preferably performed in the diluter described in connection with one of the preferred embodiments of the measurement system.

[0052] In one embodiment according to the present invention, the method - Further includes the step of releasing the pressure in the system after filling the capillary electrophoresis measurement device with the sample solution by opening the third valve located between the expansion vessel and the waste container and the fourth valve located between the supply line and the waste container, and closing the second valve.

[0053] In one embodiment according to the present invention, the method further includes closing a third valve, a fourth valve, and a fifth valve located between the capillary electrophoresis measurement device and the waste container during the step of increasing and releasing the pressure of the buffer solution and during the step of increasing and releasing the pressure of the sample solution.

[0054] In one embodiment according to the present invention, the step of filling the supply line and the capillary electrophoresis measurement device with the sample solution is repeated before applying a high voltage to the capillary for measuring the sample solution so that a plurality of sample solution units are loaded onto the capillary electrophoresis measurement device.

[0055] In the context of the present invention, a sample solution unit is the amount of sample solution loaded onto the capillary electrophoresis measurement device during one of the steps of filling the supply line with the sample solution, increasing the pressure of the sample solution in the supply line, and loading the sample solution into the capillary.

[0056] By loading a plurality of sample solution units, the number of measurements can be reduced, and thus the cost can be lowered.

[0057] In one embodiment according to the present invention, the method - the step of filling the supply line with the buffer solution by supplying the buffer solution into the supply line after loading the buffer solution into the capillary further includes.

[0058] It will be apparent to those skilled in the art that the structural features described for the measurement system and the water measurement system can be applied to this method, and that the method steps described for this method can be applied on the measurement system and the water measurement system.

[0059] Further advantages, features, and details are revealed based on the preferred embodiments of this specification to which the accompanying drawings are referred.

Brief Description of the Drawings

[0060]

Figure 1

Figure 2A

Figure 2A-1

Figure 2A-2

Figure 2A-3

Figure 2B

Figure 2C

Figure 2D

Figure 2E

Figure 3

Embodiments for Carrying Out the Invention

[0061] The measurement system 2 (FIG. 1) includes an inlet 4 including a multi-valve in the illustrated embodiment. The inlet 4 is connected to the first end 8 of the supply line 6. The supply line 6 extends between the first end 8 and the second end 10, and the second end 10 is connected to a three-way valve 12. The flow direction F is from the first end 8 to the second end 10 of the supply line. The pump 14 is located on the supply line 6. Further, an expansion line 16 is attached to the supply line 6 downstream from the pump 14. The expansion line 16 extends from the supply line 6 to an expansion vessel 18 and a first valve V 1is provided. The expansion vessel 18 includes a housing 20, and a membrane 22 is provided within the housing 20 to define an internal space 24a and a gas space 24b. The internal space 24a is in fluid contact with the expansion line 16, and the gas space 24b contains air. Further, a waste line 26 of the expansion vessel is operably connected to the internal space 24a, and a third valve V 3 is provided thereon. The waste line of the expansion vessel extends toward a waste container 28. The expansion vessel 18 is further provided with a pressure sensor 23, a pressure gauge in the illustrated embodiment.

[0062] The supply line 6 further includes a second valve V 2 located downstream of the expansion line 16. A fourth valve V 4 is provided, and a waste supply line 30 extending toward the waste container 28 is operably connected to the supply line 6.

[0063] The measuring device 13 is connected to a three-way valve. The measuring device 13 includes a first T-piece 32, a second T-piece 34, a cation capillary 36, an anion capillary 38, a buffer cation container 40, a buffer anion container 42, and high-voltage circuits 48 and 50. The three-way valve 12 is operably connected to the first T-piece 32 and the second T-piece 34. The leg of the first T-piece 32 is the cation capillary 36, and the leg of the second T-piece 34 is the anion capillary 38. The cation capillary 36 extends toward the buffer cation container 40, and the anion capillary 38 extends toward the buffer anion container 42. The first T-piece 32 includes a fifth valve V 5 at the opposite end of the three-way valve 12 on the cross member, and the second T-piece 34 includes a sixth valve V 6 at the opposite end of the three-way valve 12 on the cross member. The fifth valve V 5 and the sixth valve V 6Both are respectively located on waste lines 44 and 46 of the measuring device extending towards the waste container. The first high-voltage circuit 48 is connected from the buffer cation container 40 to the first T-piece 32, and the second high-voltage circuit 50 is connected from the buffer anion container 42 to the second T-piece 34. In the illustrated embodiment, the first capillary 36 is provided with the first non-contact conductivity sensor 37, and the second capillary 38 is provided with the second non-contact conductivity sensor 39. It is obvious to those skilled in the art that other detectors or sensors such as ultraviolet sensors are also possible.

[0064] While the closed valve is shown colored, the open valve is shown by its outline.

[0065] The measuring system 2 (FIG. 2A) is configured to fill the supply line 6 with the buffer cation solution by supplying the buffer solution through the inlet 4 at the first end 8 of the supply line 6 in the first step. In the first step, the second valve V 2 is opened. In this first step, the inlet 4 can be connected to the buffer cation container. In the first step, the first valve V 1 , the second valve V 2 , the third valve V 3 , the fourth valve V 4 , and the fifth valve V 5 are open. The three-way valve 12 is closed towards the second T-piece 34 and open towards the first T-piece 32. Hereinafter, only the measurement using the first capillary 36 will be described, so the three-way valve 12 remains closed towards the second T-piece 34. The pump 14 is operating to fill the measuring system 2 with the buffer solution up to the first capillary 36.

[0066] Alternatively or additionally, the first step can be divided into sub-steps. For example, in the first sub-step (FIG. 2A-1) of the first step, the second valve V 2 is closed, but the first valve V 1 , the third valve V 3 , the fourth valve V 4 , and the fifth valve V 5is open. In the method of the first sub-step, the expansion vessel 18 is filled with a buffered cation solution. In the second sub-step (FIG. 2A-2) of the first step, the first valve V 1 and the fifth valve V 5 are closed, but the second valve V 2 the third valve V 3 and the fourth valve V 4 are open. In the second sub-step, the supply line 6 and the supply waste line 30 are filled with a buffered cation solution. In the third sub-step (FIG. 2A-3) of the first step, the first valve V 1 and the fourth valve V 4 are closed, but the second valve V 2 the third valve V 3 and the fifth valve V 5 are open. In the third sub-step, the T-piece 32 and the measurement waste line 44 are filled with a buffered cation solution.

[0067] In the second step (FIG. 2B), the measurement system 2 is configured to accumulate the pressure of the buffer solution in the supply line 6. In the second step, the second valve V 2 the third valve V 3 the fourth valve V 4 and the fifth valve V 5 are closed. Then, since the first valve V 1 is still open and the valve V 3 is closed, the pump 14 is operated to accumulate the pressure in the expansion vessel 18. The inlet 4 is still connected to the buffered cation solution container.

[0068] In the third step (FIG. 2C), the measurement system 2 is configured to insert the buffer solution into the first capillary 36 of the measurement device 13. Compared with the second step, the second valve V 2 is open to let the buffer solution into the first capillary 36. When the pressure sensor 23 indicates that the pressure is high enough for the first capillary 36 to be filled, the pump 14 is stopped.

[0069] In the fourth step, the measurement system 2 is configured to fill the supply line 6 with the sample solution. The fourth step includes the same configuration as that shown for the first step (FIG. 2A), the difference being that the sample solution container is connected to the inlet 4. By operating the pump 14, the measurement system 2 is filled with the sample solution up to the first capillary 36.

[0070] In the fifth step, the measurement system 2 is configured to accumulate the pressure of the sample solution in the supply line 6. The fifth step includes the same configuration as that shown for the second step (FIG. 2B), the difference being that the sample solution container is connected to the inlet 4. Then, since the first valve V 1 is open and the third valve V 3 is closed, the pump 14 is operated to accumulate the pressure in the expansion container 18.

[0071] In the sixth step, the measurement system 2 is configured to insert the sample solution into the first capillary 36 of the measuring device 13. The sixth step includes the same configuration as that shown for the third step (FIG. 2C), the difference being that the sample solution container is connected to the inlet 4. The second valve V 2 is briefly opened for a predetermined time period to place a predetermined amount of the sample solution into the first capillary 36. While the second valve V 2 is open, the pump 14 is not operating, and thus the amount of the sample solution inserted into the capillary 36 is determined by the pressure accumulated during the predetermined time period when the valve V 2 is open.

[0072] In the seventh step (FIG. 2D), the measurement system 2 is configured to release the pressure within the measurement system 2. In the seventh step, the second valve V 2 and the fifth valve V 5 are closed, but the third valve V 3 and the fourth valve V 4 are open, whereby the pressurized processing liquid can flow towards the waste container 28.

[0073] In the eighth step, the measuring system 2 is configured to fill and / or wash the measuring system 2 with a buffered cation solution. The eighth step includes the same configuration as that shown for the first step (Figure 2A). The inlet 4 is connected again to the buffered cation solution container. In the eighth step, the first valve V 1 , the second valve V 2 , the third valve V 3 , the fourth valve V 4 , and the fifth valve V 5 are open. Then, the pump 14 is operated to wash the piping of the measuring system 2 with the buffer solution.

[0074] Alternatively or additionally, the eighth step may be divided into sub-steps. For example, in the first sub-step (Figure 2A-1) of the eighth step, the second valve V 2 is closed, but the first valve V 1 , the third valve V 3 , the fourth valve V 4 , and the fifth valve V 5 are open. In the method of the first sub-step, the expansion container 18 is filled with the buffered cation solution. In the second sub-step (Figure 2A-2) of the eighth step, the first valve V 1 and the fifth valve V 5 are closed, but the second valve V 2 , the third valve V 3 , and the fourth valve V 4 are open. In the second sub-step, the supply line 6 and the supply waste line 30 are filled with the buffered cation solution. In the third sub-step (Figure 2A-3) of the eighth step, the first valve V 1 and the fourth valve V 4 are closed, but the second valve V 2 , the third valve V 3 , and the fifth valve V 5 are open. In the third sub-step, the T-piece 32 and the measurement waste line 44 are filled and / or washed with the buffered cation solution.

[0075] In the ninth step (Figure 2E), the measurement system 2 is configured to perform measurements using a non-contact conductivity sensor 37 provided on the first capillary 36. In the ninth step, a high voltage is applied to the high voltage circuit 48, and the high voltage moves the ions of the sample solution from the T-piece 32 towards the buffer cation container 40. The non-contact conductivity sensor 37 measures the ions in the sample solution. In the ninth step, the second valve V 2 , the third valve V 3 , and the fourth valve V 4 are closed. This ensures that the buffer solution remains in the T-piece 32 to guarantee correct measurements while the voltage is applied by the high voltage circuit 48.

[0076] The water measurement system 52 (Figure 3) includes the measurement system 2 connected to the water system 54 of greenhouse horticulture. For example, other water systems for industrial or agricultural water treatment can also be connected to the measurement system 2. The measurement system 2 can be connected to the water system 54 either in-line or at-line. Additionally or alternatively, a loading module 55 is connected to the inlet 4 of the measurement system 2. The loading module 55 includes a cleaning solution container 56 and a buffer solution container 58. The buffer solution container 58 can contain a cation buffer solution or an anion buffer solution. The cleaning solution container 56 can contain a base such as a sodium hydroxide (NaOH) solution or an acid such as hydrochloric acid (HCl). The cleaning solution container 56 can further contain ultrapure water for cleaning the measurement system 2. The loading module 55 can further include a calibration solution container 60 containing a calibration cation solution and / or a calibration anion solution. The loading module 55 can be easily coupled and separated to the inlet 4 to easily supply reagents to the measurement system 2. In one embodiment, the water system 54 is operably connected to the cleaning solution container 56. In an alternative embodiment, the loading module 55 includes only the buffer solution container 58 for supplying the buffer solution to the measurement system 2.

[0077] Periodically, a calibration solution, which can also be shown as a standard solution, is inserted into capillary 36 and capillary 38 in the same way as the buffer solution, and the sample solution is inserted into capillary 36 and capillary 38. This calibration solution is measured. The concentration of ions in the calibration solution is known and can thus serve as a calibration for the sample. The peaks of the calibration solution measured via sensors 37 and 39 can be compared with the peaks of the measurement results of the sample solution. This comparison can determine the concentration of ions in the sample solution.

[0078] If the deviation of the peak of the calibration solution is higher than a predetermined peak of the ion concentration, the system 52 automatically starts cleaning using the cleaning solution. After cleaning the system 52, the calibration solution can be inserted again into capillary 36 and capillary 38 to measure the peak of the ion concentration and compare it with the predetermined peak. If the measured peak is within the predetermined bandwidth, the system 52 can continue to measure the sample solution. If the measured peak is not within the predetermined bandwidth, the system 52 can inform the operator to perform maintenance, for example, via the controller.

[0079] In one of the presently preferred embodiments, the measurement system 2 is facing a sample having a varying concentration. In such an embodiment, the measurement system 2 is provided with a dilution system or alternatively is connected to a dilution system. In such a case, additional information about the sample source, such as conductivity or an estimated concentration, can be known. This information is provided (manually) to the dilution controller as a first input. The dilution controller can be a separate controller or can be integrated within the controller of the measurement system 2. A conductivity sensor or any other suitable sensor provides the conductivity as a second input, as an input parameter on which the dilution can be based. The dilution controller collects all the data and calculates the required dilution factor. This factor is then preferably used by a dilution system having actions on a multi-valve, flow and time, and an optional mixing device to ensure that the actual dilution takes place. The dilution system dilutes the sample, for example, with ultrapure water in a mixing tank. Preferably, the sample is diluted and the measurement is performed. Peaks are detected using sensors 37 and / or 39 and the areas of these peaks are calculated to identify specific ions. To prevent problems associated with peaks that are too high, the sample requires a higher dilution factor. This information is an input for dilution control. After the measurement, the used (and unused) liquid is discharged. Optionally, an external system may provide information about the first and / or second input to the dilution controller.

[0080] In a further preferred embodiment, the measurement system 2 includes and / or is operably connected to other detectors. Such other detectors may include one or more of capacitively-coupled contactless conductivity detectors (C4D), ultraviolet-visible spectroscopy detection (UV / VIS), single wavelength detectors (SWD), mass spectrometers (MS), fluorescence detectors (FLD), variable wavelength detectors (VWD), diode array detectors (DAD), also known as photodiode array (PDA) detectors, refractive index detectors (RID), and charged aerosol detectors (CAD).

[0081] The present invention is in no way limited to the preferred embodiments of the specification described above. The rights sought are defined by the appended claims, and within their scope many modifications are possible.

Explanation of Reference Numerals

[0082] 2 Measurement system 4 Inlet 6 Supply line 8 First end 10 Second end 12 Three-way valve 13 Measurement device 14 Pump 16 Expansion line 18 Expansion vessel 20 Housing 22 Membrane 23 Pressure sensor 24a Internal space 24b Gas space 26 Waste line of the expansion vessel 28 Waste container 30 Waste supply line 32 First T-piece 34 Second T-piece 36 Cationic capillary 37 First non-contact conductivity sensor 38 Anionic capillary 39 Second non-contact conductivity sensor 40 Buffer cation container 42 Buffer anion container 44 Measurement device waste line 46 Measurement device waste line 48 High-voltage circuit 50 High-voltage circuit 52 Water measurement system 54 Water system 55 Loading module 56 Cleaning solution container 58 Buffer solution container 60 Calibration solution container

Claims

1. A measurement system for measuring the ion concentration in a processing liquid using capillary electrophoresis, comprising: A supply line extending between a first end and a second end, having a flow direction from the first end to the second end; An inlet connected to the supply line at the first end; A pump provided in the supply line; An expansion vessel connected to the supply line by an expansion line, the expansion line being provided with a first valve; A capillary electrophoresis measurement device connected to the supply line at the second end; And comprising; The pump, the first valve, and the expansion vessel cooperate to accumulate and release pressure for loading a sample into the capillary electrophoresis measurement device. A measurement system.

2. The measurement system according to claim 1, wherein the supply line includes a second valve located between the pump and the second end of the supply line.

3. The capillary electrophoresis measurement device according to claim 1 or 2, comprising a first capillary and a second capillary, wherein the first capillary is an anion capillary and the second capillary is a cation capillary. Measurement system.

4. The capillary electrophoresis measurement device is connected to a three-way valve that connects the second end of the supply line to the first capillary and the second capillary, and both the first capillary and the second capillary are preferably in contact with a related buffer solution container. The measurement system according to claim 3.

5. The measurement system according to claim 4, wherein the three-way valve and the first capillary and the second capillary are each connected to a respective T-piece.

6. The measurement system according to any one of claims 1 to 5, further comprising a waste container operably connected to the expansion vessel, the supply line, and / or the capillary electrophoresis measurement device.

7. The measurement system according to claim 6, wherein each of the expansion vessel, the supply line, and the capillary electrophoresis measurement device is operably connected to the waste container by a respective line, and each line is provided with a valve.

8. The measurement system according to any one of claims 1 to 7, further comprising a pressure sensor connected to the expansion vessel.

9. The capillary electrophoresis measurement device includes a voltage circuit provided on the capillary, and is the measurement system according to any one of claims 1 to 8.

10. The capillary electrophoresis measurement device includes a non-contact conductivity detector, and is the measurement system according to any one of claims 1 to 9.

11. The inlet includes a multi-valve, and is the measurement system according to any one of claims 1 to 10.

12. The multi-valve is connected to a second buffer solution container and a sample solution inlet so that a buffer solution and a sample solution can be supplied into the supply line, and is the measurement system according to claim 11.

13. The measurement system according to any one of claims 1 to 12 further includes a loading module including a buffer solution and / or a sample solution operably connected to the inlet.

14. The measurement system according to any one of claims 1 to 13 further includes a dilution controller configured to dynamically dilute the sample solution, preferably dilute the sample solution with ultrapure water.

15. A water measurement system such as a horticultural water measurement system, including the measurement system according to any one of claims 1 to 14, and a water system operably connected to the inlet to supply a sample solution is provided, and is a water measurement system.

16. A method for measuring the ion concentration in a processing solution using capillary electrophoresis, comprising the step of filling a supply line and a capillary electrophoresis measurement device with a buffer solution by using an expansion container, the step of filling the supply line and the capillary electrophoresis measurement device with a sample solution by using the expansion container, and the step of applying a high voltage to the capillary to measure the sample solution by using a detector of the capillary electrophoresis measurement device is provided, and is a method.

17. The step of filling the supply line and the capillary electrophoresis measurement device with the buffer solution includes the step of supplying the buffer solution through an inlet at a first end of the supply line and opening a second valve located on the supply line toward the capillary electrophoresis measurement device located at a second end of the supply line to fill the supply line with the buffer solution, Operating a pump located on the supply line between the inlet and the second valve, and opening the first valve towards the expansion vessel and closing the second valve to increase the pressure of the buffer solution in the supply line; Releasing the pressurized buffer solution towards the capillary electrophoresis measurement device by opening the second valve to fill the capillary with the buffer solution; The method according to claim 16, comprising:

18. The step of filling the supply line and the capillary electrophoresis measurement device with the sample solution comprises: Supplying the sample solution through the inlet and opening the second valve to fill the supply line with the sample solution; Operating the pump, opening the first valve towards the expansion vessel and closing the second valve to increase the pressure of the sample solution in the supply line; Loading the sample solution into the capillary by opening the second valve to release the pressurized sample solution towards the capillary electrophoresis measurement device; The method according to claim 17, comprising:

19. The step of diluting the sample solution before filling the supply line with the sample solution; Further comprising: Preferably, the method according to claim 18, wherein the sample solution is dynamically diluted based on a pre-measurement of the sample solution.

20. Opening a third valve located between the expansion vessel and the waste container and a fourth valve located between the supply line and the waste container, and closing the second valve to release the pressure in the system after filling the capillary electrophoresis measurement device with the sample solution; The method according to any one of claims 17 to 19, further comprising:

21. The method according to claim 20, further comprising closing the third valve, the fourth valve, and a fifth valve located between the capillary electrophoresis measurement device and the waste container during the step of increasing and releasing the pressure of the buffer solution and during the step of increasing and releasing the pressure of the sample solution.

22. The step of filling the supply line and the capillary electrophoresis measurement device with the sample solution is repeated before applying a high voltage to the capillary to measure the sample solution such that a plurality of sample solution units are loaded into the capillary electrophoresis measurement device, the method according to any one of claims 16 to 21.

23. The step of filling the supply line with the buffer solution by supplying the buffer solution through an inlet after loading the buffer solution into the capillary The method according to any one of claims 16 to 22, further comprising.

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