A sample loading valve for a liquid chromatography apparatus and the liquid chromatography apparatus

Abstract

This invention discloses a sample loading valve for a liquid chromatography apparatus and the liquid chromatography apparatus itself. The sample loading valve includes a stator and a rotor, the rotor being rotatably connected to the end face of the stator. The end face of the stator has multiple interfaces, at least one of which is a sample loading pump interface connected to a sample loading pump. The rotor has multiple end face flow channels and through holes on its end face engaging with the stator. A second layer of flow channels is provided inside the rotor, communicating with the end face flow channels and / or the end face of the rotor through the through holes. The sample loading valve is configured to: as the rotor rotates, without stopping the sample loading pump, maintain unobstructed flow within the sample loading valve using the second layer of flow channels, and automatically switch flow paths to achieve sample loading. This invention adds a second layer of flow channels inside the rotor, enabling the sample loading valve to switch flow paths and achieve sample loading without stopping the sample loading pump.

Description

Technical Field

[0001] This invention relates to the field of fluid control technology for liquid chromatography equipment, and specifically to a sample loading valve and a liquid chromatography device. Background Technology

[0002] In the separation and preparation process of liquid chromatography equipment, sample loading is a crucial step, usually accomplished through a loading valve and a quantitative loop. The traditional workflow is as follows: First, the valve is switched to the "loading" position, allowing the sample solution to flow through the quantitative loop via a syringe or loading plunger pump, filling it completely; then, the valve is switched to the "injection" position, switching the flow path of the mobile phase driven by the high-pressure plunger pump to flow through the quantitative loop, thereby "pushing" a quantified sample into the chromatography column for separation.

[0003] However, during the switching of a traditional sample loading valve from the "loading" to the "injection" position, to avoid extremely high pressure surges caused by momentary blockage of the high-pressure plunger pump outlet flow path due to the internal flow channel switching, which could lead to pipe rupture, joint leakage, or pump head damage, the high-pressure plunger pump usually needs to be paused or set to an extremely low flow rate. The starting and stopping of the plunger pump causes drastic fluctuations in system pressure and interrupts or pulsations in the flow to detectors (such as UV detectors). This results in attenuation of the critical UV detection signal, baseline drift, or even data loss at the moment of switching, severely affecting the accuracy and reproducibility of the analytical results. Furthermore, frequent starting and stopping of the plunger pump increases mechanical wear on the equipment and reduces overall operating efficiency.

[0004] Existing sample loading valve designs typically require manual intervention of the plunger pump during switching, such as slowing down or pausing it, or cannot achieve continuous, automated multiple sample loading operations within a single run, resulting in insufficient flexibility. Therefore, developing a sample loading valve capable of smooth, shock-free automated sample loading switching while the plunger pump is running continuously and stably, and supporting continuous operation, is of great significance for improving the performance, data quality, and work efficiency of liquid chromatography systems. Summary of the Invention

[0005] In view of the above problems, the present invention is proposed to provide a sample loading valve for a liquid chromatography apparatus that overcomes or at least partially solves the above problems.

[0006] According to one aspect of an embodiment of the present invention, a sample loading valve for a liquid chromatography apparatus includes a stator and a rotor, wherein the rotor is rotatably connected to the end face of the stator. The stator has multiple interfaces on its end face, and at least one of the multiple interfaces is a sample pump interface connected to the sample pump. The rotor has multiple end face channels and through holes on the end face that engages with the stator. The rotor has a second layer of channels inside, and the second layer of channels communicates with the end face channels and / or the end face of the rotor through the through holes. The sample loading valve is configured such that, as the rotor rotates, without stopping the sample loading pump, the flow path inside the sample loading valve is kept unobstructed by utilizing the second layer of flow channel, and the flow path is automatically switched to achieve sample loading.

[0007] In some embodiments, the interface on the stator further includes at least one of the following: a quantitative loop inlet, a quantitative loop outlet; a waste liquid outlet; a chromatography column interface; and a syringe interface.

[0008] In some embodiments, the end face flow channel includes a first end face flow channel, a second end face flow channel, a third end face flow channel, a fourth end face flow channel, and a fifth end face flow channel.

[0009] In some embodiments, the through hole includes a first through hole, a second through hole, and a third through hole, wherein the first through hole is adjacent to the first end face flow channel, the second through hole is connected to the second end face flow channel, and the third through hole is connected to the third end face flow channel.

[0010] In some embodiments, the first end face flow channel, the second end face flow channel, the third end face flow channel and the fourth end face flow channel are arc-shaped, and the fifth end face flow channel is L-shaped.

[0011] In some embodiments, the second layer flow channel is a single channel that communicates with the first through hole, the second through hole, and the third through hole, respectively.

[0012] In some embodiments, the sample loading valve has a first operating state: in the first operating state, the liquid from the sample loading pump flows through the sample loading pump interface of the stator, through the second through-hole into the second laminar flow channel, into the third through-hole, and then flows out from the chromatography column inlet communicating with the third through-hole; and / or, The liquid enters from the stator's syringe interface, passes through the fifth end face flow channel, flows out from the metering ring outlet connected to the fifth end face flow channel to the external metering ring, and then flows out from the metering ring inlet through the first end face flow channel connected to the metering ring inlet and out from the waste liquid outlet.

[0013] In some embodiments, the sample loading valve has a second operating state: in the second operating state, liquid enters the second end face flow channel from the sample loading pump interface, and then enters the second layer flow channel through the second through hole communicating with the second end face flow channel. A portion of the liquid in the second layer flow channel flows out of the sample loading valve after passing through the second layer flow channel, the first through hole and the quantitative loop inlet, and another portion of the liquid in the second layer flow channel flows out of the sample loading valve after passing through the second layer flow channel, the third through hole and the chromatography column interface.

[0014] In some embodiments, the sample loading valve has a third operating state: in the third operating state, the liquid enters the second layer flow channel after passing through the sample loading pump interface of the stator, the second end face flow channel, and the second through hole, then flows out from the metering loop inlet after passing through the first through hole, and after passing through the metering loop outlet, it flows out from the chromatography column interface after passing through the fourth end face flow channel; and / or, The cleaning solvent enters through the syringe port, flows through the fifth end face channel, and then flows out from the waste liquid outlet.

[0015] According to another aspect of the present invention, a liquid chromatography apparatus includes a sample loading pump, a chromatography column, a quantitative loop, a syringe, and a sample loading valve as described in any of the above embodiments.

[0016] Compared with the prior art, the embodiments of the present invention have the following advantages: In this embodiment of the invention, the sample loading valve, by setting an independent second-layer flow channel (MPP flow channel) inside the rotor, ensures that at any moment during rotor rotation switching, the outlet of the plunger pump has at least one path connected to the downstream of the system. This fundamentally eliminates the instantaneous high pressure caused by a completely closed flow path, enabling the high-pressure plunger pump to maintain a constant flow rate from start to finish, and avoiding equipment risks caused by pressure shocks.

[0017] Because the plunger pump does not need to be stopped and started, the liquid pressure and flow rate to the chromatography column and detector remain constant, eliminating the pressure pulsations and flow fluctuations caused by traditional switching methods. This results in an exceptionally stable signal baseline for detectors such as UV detectors, effectively preventing signal attenuation, drift, or loss, and greatly improving the accuracy, reproducibility, and sensitivity of chromatographic data.

[0018] This invention, through its unique flow channel design, allows for flexible bypassing or reuse of the quantitative loop during a single run by controlling operations such as reverse rotor rotation. This provides the hardware foundation for multiple, continuous, and automated sample loading. This improves the efficiency of high-throughput screening or preparative purification.

[0019] Integrated cleaning function reduces cross-contamination. The working design includes a channel from the syringe flow path to the waste liquid port, which can be used to easily clean the syringe, quantitative loop and related flow path before and after sample loading, effectively reducing the risk of cross-contamination caused by sample residue. It is especially suitable for scenarios that require high-precision quantification or continuous analysis of different samples.

[0020] The optimized flow path layout reduces ineffective rotor rotation stroke, shortens valve switching time, and improves system response speed. Wear-resistant materials are used to manufacture core components, enhancing the valve's service life and sealing reliability under long-term high pressure and high-frequency switching. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the interface layout of the stator end face in an embodiment of the present invention.

[0022] Figure 2(a) is a schematic diagram of the end face flow channel and through hole of the rotor in an embodiment of the present invention.

[0023] Figure 2(b) is a schematic diagram of the second layer flow channel structure of the rotor in an embodiment of the present invention.

[0024] Figure 3 This is a schematic cross-sectional view of the rotor and stator after they are combined in an embodiment of the present invention.

[0025] Figure 4 This is a schematic diagram of the flow path when the sample loading valve is in the first working state in an embodiment of the present invention.

[0026] Figure 5 This is a schematic diagram of the flow path when the sample loading valve is in the second working state in an embodiment of the present invention.

[0027] Figure 6 This is a schematic diagram of the flow path when the sample loading valve is in the third working state in an embodiment of the present invention.

[0028] Attached image annotations: 1. Quantitative loop inlet; 2. Quantitative loop outlet; 3. First waste liquid outlet; 4. Second waste liquid outlet; 5. Sample pump interface; 6. Syringe interface; 7. Chromatography column interface; C1. First end face channel; C2. Second end face channel; C3. Third end face channel; C4. Fourth end face channel; C5. Fifth end face channel; M1. First through hole; M2. Second through hole; M3. Third through hole; MPP. Second laminar flow channel. Detailed Implementation

[0029] Numerous specific details are set forth in the following description to provide a full understanding of the invention. However, the invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0030] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0031] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0032] In the description of this invention, references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this invention.

[0033] In the description of this invention, "multiple" refers to two or more.

[0034] This invention discloses a sample loading valve for chromatography equipment, particularly a single sample loading valve, combined with... Figure 1-3 As shown, the sample loading valve includes a stator and a rotor, with the rotor rotatably connected to the end face of the stator. Optionally, the stator and rotor are made of wear-resistant ceramic material, and their end faces are precisely fitted together and can rotate relative to each other.

[0035] The stator has multiple interfaces on its end face, and at least one of the multiple interfaces is a sample pump interface connected to the sample pump. The rotor has multiple end face channels and through holes on the end face that engages with the stator. The rotor has a second layer of channels inside, and the second layer of channels communicates with the end face channels and / or the end face of the rotor through the through holes. The sample loading valve is configured such that, as the rotor rotates, without stopping the sample loading pump, the flow path inside the sample loading valve is kept unobstructed by utilizing the second layer of flow channel, and the flow path is automatically switched to achieve sample loading.

[0036] For details, see Figure 1 Multiple fluid interfaces are provided on the end face of the stator: quantitative loop inlet 1, quantitative loop outlet 2, first waste liquid outlet 3, second waste liquid outlet 4, chromatography column interface 7, sample loading pump interface 5, and syringe interface 6. An external quantitative loop is connected between quantitative loop inlet 1 and quantitative loop outlet 2, wherein the sample loading pump can be a high-pressure plunger pump.

[0037] Referring to Figure 2, five recessed end-face flow channels are machined on the end face of the rotor: first to fifth end-face flow channels C1, C2, C3, C4, and C5. Among them, C1, C2, C3, and C4 are arc-shaped flow channels, and C5 is an L-shaped flow channel. The rotor also has three vertical through holes: first through hole M1, second through hole M2, and third through hole M3. M1 is located near flow channel C1, second through hole M2 connects to the second end-face flow channel C2, and third through hole M3 connects to the third end-face flow channel C3. Inside the rotor, an internal second-layer flow channel MPP is machined, directly communicating with the end face. The second-layer flow channel MPP is a channel located inside the rotor; optionally, this channel has an L-shaped or other bent structure, communicating with the three through holes M1, M2, and M3 respectively.

[0038] The sample loading valve has three main operating states, and the plunger pump does not need to be stopped during the switching process: The first operating state is the bypass / loading state, when the rotor rotates to... Figure 4 The location shown.

[0039] System bypass: The liquid phase enters the sample loading valve through the sample loading pump interface 5, then enters the second through hole M2 through the second end face flow channel C2, and then flows into the second layer flow channel MPP inside the rotor, and then flows out through the third through hole M3, through the third end face flow channel C3, and finally flows to the chromatography column through the chromatography column interface 7. At this time, the system is in bypass circulation state, and the pump continues to run to balance the system.

[0040] Filling the metering loop: The operator injects the sample through the syringe port 6 using a syringe. The sample flows out from the metering loop outlet 2 through the fifth end face flow channel and enters the outer metering loop. Air or existing liquid in the metering loop is expelled, returns to the sample loading valve through the metering loop inlet 1, and then exits from the first waste liquid outlet through the first end face flow channel C1 until the metering loop is full of sample.

[0041] The second working state is an intermediate transition state, such as Figure 5 When sample injection is required, the rotor begins to rotate from the first state to the third state. At this transition position: The mobile phase from the sample pump interface 5 enters the second-layer flow channel MPP inside the rotor via the second end face flow channel C2 and the second through hole M2. At this time, due to the rotor position, the second-layer flow channel MPP (which simultaneously connects the first through hole M1 and the third through hole M3) divides the mobile phase into two paths within the second-layer flow channel MPP: one path continues to flow to the chromatography column interface 7 via the third through hole M3 and the third end face flow channel C3, maintaining the flushing of the chromatography column; the other path flows to the quantitative loop inlet 1 via the first through hole. Throughout the entire rotation switching process, the pump outlet remains connected to the chromatography column and / or quantitative loop through the internal flow channel MPP, eliminating the risk of instantaneous closure. Therefore, the pump can maintain a constant flow rate throughout the entire process.

[0042] The third working state is the sample loading state, where the rotor rotates to the position shown in the image. Figure 6 The locations shown include: Sample loading: The mobile phase from the sample loading pump interface enters the second layer flow channel MPP inside the rotor through the second end face flow channel C2 and the second through hole M2. At this time, the second layer flow channel MPP is mainly connected to the first through hole M1. The mobile phase flows out from the quantitative loop inlet 1 through the first through hole M1 and enters the external quantitative loop, "pushing" the sample stored in the quantitative loop out. The pushed-out sample returns to the sample loading valve through the quantitative loop outlet 2, flows through the fourth end face flow channel C4, and finally enters the chromatography column through the chromatography column interface 7, completing the sample loading process.

[0043] Cleaning flow path: Cleaning solvent can be injected through syringe port 6 during or after sample injection. The cleaning solvent is discharged directly from the second waste liquid outlet 4 through the fifth end face flow channel C5, used to clean the syringe and related sample loading flow path, in preparation for the next operation.

[0044] Workflow Summary: The system initially operates in the first working state, with the pump running in bypass mode while the sample is loaded into the quantitative loop using a syringe. After a sample loading command is issued, the rotor rotates through the second working state (transition) to the third working state, where the pump's mobile phase delivers the sample from the quantitative loop into the chromatography column. Throughout the entire process, the pump never stops. After sample loading is complete, the rotor can rotate in the opposite direction to re-enter the above working state. At this point, new sample can be loaded again into the emptied quantitative loop using the syringe, achieving continuous sample loading.

[0045] In summary, this invention creatively solves the problem of inevitable flow path interruption when switching the sample loading valve by setting the second flow channel MPP inside the rotor and its connection with the three through holes (M1, M2, M3), realizing continuous and stable operation of the high-pressure plunger pump throughout the sample loading process, and greatly improving the pressure stability, data quality and operating efficiency of the liquid chromatography system.

[0046] The beneficial effects brought about by the embodiments of the present invention include: In this embodiment of the invention, a second flow channel is added inside the rotor, allowing the sample loading valve to load samples without stopping the system pump.

[0047] The sample loading valve's rotor rotates in reverse during repeated sample loading, bypassing the quantitative loop. The sample loading syringe in the chromatography system can be cleaned by draining waste liquid through the waste outlet. After cleaning, rotating the valve in reverse allows for secondary sample loading of the quantitative loop.

[0048] Because the rotor flow channel optimization reduces the distance between the rotor and the stator orifice, the valve running time can be reduced. The reduced valve running time in the system can improve the performance of the chromatography system.

[0049] It should be noted that although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope defined in the claims of the present invention.

Claims

1. A sample loading valve for a liquid chromatography apparatus, the sample loading valve comprising a stator and a rotor, the rotor being rotatably connected to the end face of the stator, characterized in that, The stator has multiple interfaces on its end face, and at least one of the multiple interfaces is a sample pump interface connected to the sample pump. The rotor has multiple end face channels and through holes on the end face that engages with the stator. The rotor has a second layer of channels inside, and the second layer of channels communicates with the end face channels and / or the end face of the rotor through the through holes. The sample loading valve is configured such that, as the rotor rotates, without stopping the sample loading pump, the flow path inside the sample loading valve is kept unobstructed by utilizing the second layer of flow channel, and the flow path is automatically switched to achieve sample loading.

2. The sample loading valve according to claim 1, characterized in that, The interfaces on the stator also include at least one of the following: a quantitative loop inlet, a quantitative loop outlet; a waste liquid outlet; a chromatography column interface; and a syringe interface.

3. The sample loading valve according to claim 2, characterized in that, The end face flow channels include a first end face flow channel, a second end face flow channel, a third end face flow channel, a fourth end face flow channel, and a fifth end face flow channel.

4. The sample loading valve according to claim 3, characterized in that, The through hole includes a first through hole, a second through hole, and a third through hole. The first through hole is adjacent to the first end face flow channel, the second through hole is connected to the second end face flow channel, and the third through hole is connected to the third end face flow channel.

5. The sample loading valve according to claim 4, characterized in that, The first end face flow channel, the second end face flow channel, the third end face flow channel and the fourth end face flow channel are arc-shaped, and the fifth end face flow channel is L-shaped.

6. The sample loading valve according to claim 4 or 5, characterized in that, The second layer flow channel is a single channel that is connected to the first through hole, the second through hole, and the third through hole, respectively.

7. The sample loading valve according to claim 6, characterized in that, The sample loading valve has a first operating state: in the first operating state, the liquid from the sample loading pump flows through the sample loading pump interface of the stator, through the second through hole into the second laminar flow channel, and into the third through hole, and then flows out from the chromatography column inlet connected to the third through hole; and / or, The liquid enters from the stator's syringe interface, passes through the fifth end face flow channel, flows out from the metering ring outlet connected to the fifth end face flow channel to the external metering ring, and then flows out from the metering ring inlet through the first end face flow channel connected to the metering ring inlet and out from the waste liquid outlet.

8. The sample loading valve according to claim 6, characterized in that, The sample loading valve has a second working state: in the second working state, the liquid enters the second end face flow channel from the sample loading pump interface, and then enters the second layer flow channel through the second through hole connected to the second end face flow channel. A part of the liquid in the second layer flow channel flows out of the sample loading valve after passing through the second layer flow channel, the first through hole and the quantitative loop inlet. Another part of the liquid in the second layer flow channel flows out of the sample loading valve after passing through the second layer flow, the third through hole and the chromatography column interface.

9. The sample loading valve according to claim 6, characterized in that, The sample loading valve has a third operating state: in the third operating state, the liquid enters the second layer flow channel after passing through the sample loading pump interface of the stator, the second end face flow channel, and the second through hole, then flows out from the metering loop inlet after passing through the first through hole, and after passing through the metering loop outlet, it flows out from the chromatography column interface after passing through the fourth end face flow channel; and / or, The cleaning solvent enters through the syringe port, flows through the fifth end face channel, and then flows out from the waste liquid outlet.

10. A liquid chromatography apparatus, characterized in that, The liquid chromatography apparatus includes a sample pump, a chromatography column, a quantitative loop, a syringe, and a sample valve as described in any one of claims 1-9.

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