Gel permeation chromatograph system

Abstract

The utility model relates to a gel permeation chromatograph system which comprises a sample injection system, a conveying system, a detection system and a waste liquid collection system which are connected in sequence, the sample injection system comprises a first sample injection branch and a second sample injection branch, the first sample injection branch is provided with a sample injection container filled with a mobile phase and a first water absorption drying device, and the second sample injection branch is provided with a second water absorption drying device; the second sample injection branch is provided with an automatic sample injector filled with a to-be-detected sample, the conveying system comprises a degasser and is connected with the sample injection system, the conveying system conveys the to-be-detected sample and a mobile phase entering from the sample injection system to the detection system, the detection system detects the to-be-detected sample, and the waste liquid collection system is used for collecting waste liquid. The degasser is arranged in the gel permeation chromatograph system, the mobile phase and the to-be-tested sample do not need to be subjected to additional degassing treatment, the degassing treatment can be completed in the gel permeation chromatograph system, and the testing efficiency is improved; by arranging the first water absorbing and drying device and the second water absorbing and drying device, moisture in a mobile phase and a sample to be tested is removed, so that the testing precision is improved.

Description

Technical Field

[0001] This application relates to the field of polymer molecular weight and distribution determination technology, and in particular to a gel permeation chromatography system. Background Technology

[0002] Gel permeation chromatography (GPC) is an instrument used in materials science, chemistry, and chemical engineering. Because GPC can be used not only for the separation and identification of small molecules, but also for the analysis of homologues of polymers with the same chemical properties but different molecular volumes, it can measure the molecular weight and distribution of polymers based on the theory of the displacement volume of polymer solutions within the gel pores, and obtain the compositional distribution of copolymers using a UV detector. The test requires a mobile phase and the sample to be tested. The mobile phase is a mixture of solute and solvent. Bubbles are generated during the mixing of the solute and solvent, and these bubble peaks affect the accuracy of the test.

[0003] In existing technologies, a special device is required to remove air bubbles, i.e., degassing, before the mobile phase enters the gel permeation chromatograph. This degassing process is complex and has low testing efficiency, while the sample cannot be degassed before injection. Furthermore, if the solute in the mobile phase is highly hygroscopic, it will absorb moisture as the storage time in the laboratory increases, and the resulting water peaks will also affect the accuracy of the test. Utility Model Content

[0004] To overcome the problems existing in related technologies, this application provides a gel permeation chromatography system that improves testing accuracy.

[0005] According to an embodiment of this disclosure, a gel permeation chromatography system is provided, comprising:

[0006] The sample introduction system includes a first sample introduction branch and a second sample introduction branch. The first sample introduction branch is used to supply the flow of the mobile phase. Along the flow direction of the mobile phase, a sample introduction container and a first water absorption and drying device are sequentially arranged on the first sample introduction branch. The second sample introduction branch is used to supply the flow of the sample to be tested. Along the flow direction of the sample to be tested, an autosampler and a second water absorption and drying device are sequentially arranged on the second sample introduction branch.

[0007] The delivery system includes a degasser and at least one delivery branch connected to the outlet end of the degasser. The inlet end of the degasser is connected to the first injection branch and the second injection branch, respectively. The mobile phase and the sample to be tested are mixed in the degasser to form a mixed medium.

[0008] The detection system includes a photodetector, a column oven, and a light scattering instrument connected in sequence, wherein the photodetector is connected to the end of the conveying branch that is furthest from the degasser;

[0009] The waste liquid collection system is connected to the output terminal of the light scattering instrument.

[0010] In some embodiments, two conveying branches are provided, referred to as the first conveying branch and the second conveying branch respectively. The conveying system further includes a control valve, and the first conveying branch and the second conveying branch are connected in parallel between the control valve and the degasser.

[0011] The control valve is in the open state, and the mobile phase and the sample to be tested flow in the injection system and the delivery system.

[0012] In some embodiments, the control valve is connected to the light scattering instrument via a pipeline.

[0013] In some embodiments, a chromatography pump is provided on the first delivery branch and the second delivery branch, respectively.

[0014] In some embodiments, one-way valves are provided at both ends of the chromatography pump along the flow direction of the mixed medium.

[0015] In some embodiments, both the first water-absorbing and drying device and the second water-absorbing and drying device are provided with a water-absorbing and desiccant.

[0016] In some embodiments, the first water-absorbing and drying device is detachably mounted to the first sample inlet branch via a first detachable structure; and / or,

[0017] The second water-absorbing and drying device is detachably installed on the second sample inlet branch via a second detachable structure.

[0018] In some embodiments, the sample inlet container is connected to the first water absorption and drying device via a six-way valve.

[0019] In some embodiments, the autosampler is a cone that is wider at the top and narrower at the bottom, and a tube is disposed inside the autosampler. The bottom end of the tube is located at the bottom of the autosampler, and the top end of the tube is connected to the input end of the first water-absorbing and drying device.

[0020] In some embodiments, the degasser is a fully automatic circulating degasser.

[0021] The technical solutions provided by the embodiments of this application may include the following beneficial effects: a degassing machine is installed inside the gel permeation chromatography system, so that the mobile phase and the sample to be tested do not need to be degassed separately, and can be completed in the gel permeation chromatography system, thereby improving the testing efficiency; by setting a first water-absorbing drying device and a second water-absorbing drying device, the moisture in the mobile phase and the sample to be tested is removed, thereby improving the testing accuracy.

[0022] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0023] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0024] Figure 1 This is a schematic diagram of a gel permeation chromatography system according to an exemplary embodiment.

[0025] Figure label:

[0026] 1. Sample introduction system; 11. First sample introduction branch; 111. Sample introduction container; 112. First water absorption and drying device; 12. Second sample introduction branch; 121. Automatic sampler; 122. Second water absorption and drying device;

[0027] 2. Conveying system; 21. Degasser; 22. Conveying branch; 221. Check valve; 222. Chromatographic pump; 23. Control valve;

[0028] 3. Detection system; 31. Photodetector; 32. Column oven; 33. Light scattering instrument;

[0029] 4. Waste liquid collection system. Detailed Implementation

[0030] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0031] like Figure 1 As shown, a gel permeation chromatography system includes a sample injection system 1, a delivery system 2, a detection system 3, and a waste collection system 4 connected in sequence. The sample injection system 1 provides an inlet for inserting the sample to be tested. The delivery system 2 transports the sample and mobile phase from the sample injection system 1 to the detection system. The detection system performs detection on the sample to obtain the desired detection data. After the detection system completes the detection, the hazardous or waste media generated after the detection is discharged into the waste collection system 4 to avoid pollution to the surrounding environment.

[0032] The sample introduction system 1 includes a first sample introduction branch 11 and a second sample introduction branch 12. Along the flow direction of the mobile phase, the first sample introduction branch 11 is sequentially connected to a sample introduction container 111 and a first water-absorbing and drying device 112 via a pipeline. The sample introduction container 111 contains the mobile phase, which is then dried by the first water-absorbing and drying device 112. The mobile phase is obtained by dissolving a solute and a solvent together. A commonly used mobile phase is a solution of X mol / L lithium bromide and N,N dimethylformamide dissolved together, where X is selected as 0.05 or 0.1 depending on the specific situation. Lithium bromide is the solute, and N,N dimethylformamide is the solvent. When lithium bromide and N,N dimethylformamide are mixed, bubbles will form, resulting in bubble peaks that affect the test results. Using lithium bromide and N,N dimethylformamide as a mobile phase offers advantages such as excellent solubility, improved separation efficiency, good chemical stability, reduced toxicity risk, improved peak shape, and a wide range of potential applications. The mobile phase and stationary phase are two important components of a gel permeation chromatography (GPC) system. The main function of the mobile phase is to carry the components in the sample through the chromatographic column and separate them on the stationary phase. The stationary phase remains stationary during the chromatographic separation process and is located inside the chromatographic column.

[0033] Along the flow direction of the sample to be tested, an autosampler 121 and a second water-absorbing and drying device 122 are sequentially installed on the second injection branch 12. Any two adjacent devices are connected by a pipeline. The sample to be tested is placed inside the autosampler 121, and the sample is dried by the second water-absorbing and drying device 122. The sample in the autosampler 121 requires pretreatment. The pretreatment process involves dissolving B mg of sample in an A mol / L mobile phase, cooling the solution, and then bringing the volume to C ml. The solution is then set aside for later use. Here, A is the same as the value of X mentioned above, B is 3-5, and C is 5-10.

[0034] When the mobile phase and the sample to be tested enter the gel permeation chromatography system, they are first dried by the first water-absorbing drying device 112 and the second water-absorbing drying device 122, respectively, to avoid the water vapor carried in them affecting subsequent detection, and to ensure that all media delivered to the subsequent detection system are in a dry state, thus ensuring the reliability and accuracy of the detection process.

[0035] The conveying system 2 includes a degasser 21 and at least one conveying branch 22 connected to the outlet of the degasser 21. The inlet of the degasser 21 is connected to the first sample inlet branch 11 and the second sample inlet branch 12 via pipelines. The mobile phase and the sample to be tested are mixed in the degasser 21 to form a mixed medium. The degasser 21 is an automatic degassing device. After the mobile phase and the sample to be tested pass through the degasser 21, the gas and moisture in the mixed medium are removed.

[0036] In one example, the delivery system 2 may include a degasser 21 and a delivery branch 22 connected to the outlet of the degasser 21. The inlet of the degasser 21 is connected to a first sample inlet branch 11 and a second sample inlet branch 12 via pipelines. The mobile phase and the sample to be tested are mixed in the degasser 21 to form a mixed medium that enters the delivery branch 22. Setting up a single delivery branch 22 is simple in structure, low in cost, and suitable for applications with small delivery volumes.

[0037] In another example, the delivery system 2 may include a degasser 21 and two delivery branches 22 connected to the outlet of the degasser 21. The two delivery branches 22 are arranged in parallel. The inlet of the degasser 21 is connected to a first injection branch 11 and a second injection branch 12 via pipelines. The mobile phase and the sample to be tested are mixed in the degasser 21 to form a mixed medium, which then enters the two delivery branches 22. The two delivery branches 22 improve delivery efficiency; if one injection branch malfunctions, the other delivery branch 22 can still be used, ensuring the normal operation of the gel permeation chromatography system.

[0038] Of course, it is understandable that, depending on the testing requirements, the delivery system 2 may also include a degasser 21 and multiple delivery branches 22 connected to the outlet of the degasser 21. These multiple delivery branches 22 are connected in parallel. The inlet of the degasser 21 is connected to the first sample inlet branch 11 and the second sample inlet branch 12 via pipelines. The mobile phase and the sample to be tested are mixed in the degasser 21 to form a mixed medium, which then enters the two delivery branches 22 respectively. Setting up multiple delivery branches 22 can further improve delivery efficiency. These multiple delivery branches 22 can be connected to different testing instruments, thereby performing different tests on the mixed medium.

[0039] The detection system 3 includes a photodetector 31, a column oven 32 and a light scattering instrument 33 connected sequentially through pipelines. The photodetector 31 is connected to the end of the conveying branch 22 that is away from the degasser 21.

[0040] The mixed medium first enters the photodetector 31, which is a differential refractive index detector. This detector assists in the detection of components with different molecular weight ranges within the mixed medium, providing a basis for analyzing each molecular weight component through corresponding detection signals. After analysis by the photodetector 31, the mixed medium enters the column oven 32, which contains a chromatographic column and a temperature and cold insulation device. The chromatographic column separates various compounds in the mixed medium, playing a crucial role in improving separation efficiency and the accuracy of analytical results. The temperature and cold insulation device maintains a constant temperature in the column oven 32, keeping the chromatographic column in a constant-temperature environment, reducing column expansion and contraction caused by temperature changes, stabilizing separation efficiency, improving analytical accuracy, and extending column lifespan. The light scattering instrument 33 can be a multi-angle laser light scattering instrument or a static light scattering instrument, used to detect the separated compounds.

[0041] The waste liquid collection system 4 is connected to the output end of the light scattering instrument 33 via a pipeline. The waste liquid collection system 4 includes a movable waste liquid tank for collecting the waste liquid after testing and for easy disposal.

[0042] The gel permeation chromatography system is equipped with a degasser 21, which eliminates the need for additional degassing of the mobile phase and the sample to be tested. The degassing process can be completed within the gel permeation chromatography system, thereby improving testing efficiency. By setting up a first water-absorbing drying device 112 and a second water-absorbing drying device 122, moisture in the mobile phase and the sample to be tested is removed, thereby improving the accuracy of the test.

[0043] In some embodiments, the conveying system 2 further includes a control valve 23, and when there is one conveying branch 22, the conveying branch 22 is disposed between the control valve 23 and the degasser 21.

[0044] When there are two conveying branches 22, they are designated as the first conveying branch and the second conveying branch, respectively. The first and second conveying branches 22 are connected in parallel. One or two control valves 23 can be used. When one control valve 23 is used, the first and second conveying branches are connected in parallel between the control valve 23 and the degasser 21. The control valve 23 controls the flow in all pipelines. When two control valves 23 are used, they are respectively located within the first and second conveying branches. Alternatively, one control valve 23 can be located on either the first or second conveying branch, while the other is located on the main pipeline after parallel connection. The control valve 23 controls the flow in the corresponding conveying branch 22 and the main pipeline after parallel connection.

[0045] When there are multiple conveying branches 22, they are connected in parallel. The number of control valves 23 is at least one. When only one control valve 23 is used, the first and second conveying branches 22 are connected in parallel between the control valve 23 and the degasser 21. When there are two or more control valves 23, they can be placed on the corresponding conveying branch 22 or the main pipeline after parallel connection, as needed. The control valves 23 are used to control the flow in the corresponding conveying branch 22 and the main pipeline after parallel connection.

[0046] When control valve 23 is in the open state, the mobile phase and the sample to be tested flow in the injection system 1 and the delivery system 2. That is, the mobile phase flows along the first branch and enters the degasser 21 through the first water absorption and drying device 112, and the sample to be tested flows along the second branch and enters the degasser 21 through the second water absorption and drying device 122. The mixed medium flows out of the degasser 21 and flows along the first delivery branch 22 and the second delivery branch 22 into the light scattering instrument 31. When control valve 23 is in the closed state, the mobile phase and the sample to be tested stop flowing in the injection system 1 and the delivery system 2. Therefore, the flow of the mobile phase, the sample to be tested and the mixed medium can be controlled by control valve 23.

[0047] In some embodiments, the control valve 23 is connected to the light scattering instrument 31 via a pipeline.

[0048] In some embodiments, a chromatography pump 222 is provided on the delivery branch 22, that is, a chromatography pump 222 is provided on the first delivery branch 22 and the second delivery branch 22 respectively. In this embodiment, the number of chromatography pumps 222 is set to two, and the setting of two chromatography pumps 222 can increase the flow rate. In another embodiment, of course, the number of chromatography pumps 222 can also be set to one, and the chromatography pump 222 is set on the main pipeline after the first delivery branch and the second delivery branch are connected in parallel. The setting of one chromatography pump 222 can reduce costs.

[0049] In some embodiments, one-way valves 221 are provided at both ends of the chromatography pump 222 along the flow direction of the mixed medium. Alternatively, one-way valve 221 can be provided at one end of the chromatography pump 222. The one-way valve 221 can control the flow direction of the mixed medium in the first delivery branch 22 and the second delivery branch 22, control the flow direction of the mobile phase in the first injection branch 11, and control the flow direction of the sample to be tested in the second injection branch 12, thereby preventing backflow.

[0050] In some embodiments, the first water-absorbing drying device 112 and the second water-absorbing drying device 122 are provided with a water-absorbing desiccant. The first water-absorbing drying device 112 may be provided with a container, in which the water-absorbing desiccant is located, and the two ends of the container are respectively connected to a sample injection container and a degassing machine. The second water-absorbing drying device 122 is also provided with a water-absorbing desiccant, and may also be provided with a container, in which the water-absorbing desiccant is located, and the two ends of the container are respectively connected to an autosampler and a degassing machine. The water-absorbing desiccant is a highly absorbent material, and in one embodiment it may be a highly absorbent resin.

[0051] In some embodiments, the first water-absorbing drying device 112 is detachably mounted to the first sample inlet branch 11 via a first detachable structure. The first detachable structure facilitates the replacement of the desiccant within the first water-absorbing drying device 112. The first detachable structure can be a valve body. The second water-absorbing drying device 122 is detachably mounted to the second sample inlet branch 12 via a second detachable structure. The second detachable structure facilitates the replacement of the desiccant within the second water-absorbing drying device 122. The second detachable structure can be a valve body.

[0052] In some embodiments, the sample injection container 111 is connected to the first water absorption and drying device 112 via a six-way valve. The six-way valve allows control of the flow direction of the sample to be tested. Alternatively, the autosampler 121 can also be connected to the second water absorption and drying device 122 via a six-way valve, thereby facilitating control of the flow direction of the mobile phase.

[0053] In some embodiments, the autosampler 121 is a cone-shaped device, wider at the top and narrower at the bottom. A tube is disposed inside the autosampler 121, with its bottom end located at the bottom of the autosampler 121 and its top end connected to the input end of the first water-absorbing and drying device 112. The cone-shaped design of the autosampler 121 facilitates the drawing of the mobile phase from the bottom of the autosampler 121 into the first injection branch 11, avoiding loss of the mobile phase. A support can also be provided for stable support of the autosampler 121. The autosampler 121 can automatically inject the sample to be tested into the second injection branch 12. Alternatively, the injection container 111 can be the same as the autosampler 121, facilitating the automatic injection of the mobile phase into the first injection branch 11.

[0054] In some embodiments, the degasser 21 is a fully automatic circulating degassing device, which can ensure that dissolved gases in the mobile phase and the sample to be tested are effectively removed, thereby improving the resolution of chromatographic peaks, reducing baseline drift, and thus improving the accuracy of detection.

[0055] Before use, the control valve 23 and degasser 21 can be activated to allow the mobile phase to flow along the first branch for drying and degassing. During testing, the mobile phase flows and dries along the first branch, while the sample to be tested flows and dries along the second branch. The mobile phase and the sample to be tested are mixed in the degasser 21 to form a mixed medium. The mixed medium flows sequentially through the photodetector 31, the column oven 32, and the light scattering instrument 33 for detection, and finally flows into the waste liquid tank.

[0056] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.

[0057] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A gel permeation chromatography system, characterized in that, include: The sample injection system includes a first sample injection branch and a second sample injection branch. The first sample injection branch is used to supply the flow of the mobile phase. Along the flow direction of the mobile phase, a sample injection container and a first water absorption and drying device are sequentially arranged on the first sample injection branch. The second injection branch is used to supply the flow of the sample to be tested. Along the flow direction of the sample to be tested, an automatic sampler and a second water absorption and drying device are sequentially arranged on the second injection branch. The delivery system includes a degasser and at least one delivery branch connected to the outlet end of the degasser. The inlet end of the degasser is connected to the first injection branch and the second injection branch, respectively. The mobile phase and the sample to be tested are mixed in the degasser to form a mixed medium. The detection system includes a photodetector, a column oven, and a light scattering instrument connected in sequence, wherein the photodetector is connected to the end of the conveying branch that is furthest from the degasser; The waste liquid collection system is connected to the output terminal of the light scattering instrument.

2. The gel permeation chromatography system according to claim 1, characterized in that, The conveying branch is provided in two places, referred to as the first conveying branch and the second conveying branch respectively. The conveying system also includes a control valve. The first conveying branch and the second conveying branch are connected in parallel between the control valve and the degasser. The control valve is in the open state, and the mobile phase and the sample to be tested flow in the injection system and the delivery system.

3. The gel permeation chromatography system according to claim 2, characterized in that, The control valve is connected to the light scattering instrument via a pipeline.

4. The gel permeation chromatography system according to claim 2, characterized in that, Chromatography pumps are respectively installed on the first delivery branch and the second delivery branch.

5. The gel permeation chromatography system according to claim 4, characterized in that, One-way valves are provided at both ends of the chromatographic pump along the flow direction of the mixed medium.

6. The gel permeation chromatography system according to any one of claims 1 to 5, characterized in that, Both the first and second water-absorbing drying devices are equipped with water-absorbing desiccant.

7. The gel permeation chromatography system according to any one of claims 1 to 5, characterized in that, The first water-absorbing and drying device is detachably mounted to the first sample inlet branch via a first detachable structure; and / or, The second water-absorbing and drying device is detachably installed on the second sample inlet branch via a second detachable structure.

8. The gel permeation chromatography system according to claim 1, characterized in that, The sample inlet container is connected to the first water absorption and drying device via a six-way valve.

9. The gel permeation chromatography system according to claim 1, characterized in that, The autosampler is a cone shape that is wider at the top and narrower at the bottom. A tube is installed inside the autosampler. The bottom end of the tube is located at the bottom of the autosampler, and the top end of the tube is connected to the input end of the first water-absorbing and drying device.

10. The gel permeation chromatography system according to claim 1, characterized in that, The degassing machine is a fully automatic circulating degassing device.

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