Mixing unit, mixing module, chromatographic analysis device and method

Abstract

The invention relates to the technical field of analytical instruments, in particular to a mixing unit, a mixing module and a chromatographic analysis device and method.The mixing unit comprises at least one mixing layer and at least one diffusion layer which are sequentially arranged in the flow direction of fluid; the mixing layer comprises at least one flow dividing structure, and the flow dividing structure is configured to disperse fluid flowing into the mixing layer into multiple flow paths; the diffusion layer comprises at least one special-shaped micro-channel, and the special-shaped micro-channel is configured to enable fluid flowing through the special-shaped micro-channel to generate flow direction change and / or flow velocity change. According to the mixing unit disclosed by the invention, a single-strand fluid is firstly dispersed into multiple flow paths through the flow dividing structure, so that the contact area between a sample solution and a mobile phase is increased; and the flow direction or the flow velocity of the fluid shunted by the shunting structure is forcibly changed by the special-shaped micro-channel in the diffusion layer, so that the fluid generates turbulent flow, thereby realizing molecular-level mixing of a sample solution and a mobile phase and improving the accuracy of quantitative results of chromatographic analysis and mass spectrometry.

Description

Technical Field

[0001] This application relates to the field of analytical instrument technology, and in particular to mixing units, mixing modules, chromatographic analysis apparatus and methods. Background Technology

[0002] High-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS) are widely used analytical techniques in fields such as chemistry, biology, and medicine.

[0003] During analysis, samples typically need to be dissolved in a suitable sample solvent to form a sample solution, which is then introduced into the system via an injector. However, in practice, samples are often dissolved in strong solvents such as methanol, acetonitrile, or dimethyl sulfoxide (DMSO), while the mobile phase is usually a mixture of buffer salts and an organic phase. This mismatch in strength, polarity, and pH between the sample solvent and the mobile phase inevitably leads to solvent effects, resulting in peak tailing, leading peaks, or even double-headed peaks, thus reducing the accuracy of quantitative results in chromatographic and mass spectrometric analyses. Summary of the Invention

[0004] This application provides a mixing unit for use in a chromatography system, comprising: At least one mixing layer and at least one diffusion layer are sequentially arranged along the fluid flow direction; The hybrid layer includes: At least one flow splitting structure, the flow splitting structure being configured to disperse the fluid flowing into the mixing layer into multiple flow paths; The diffusion layer includes: At least one irregularly shaped microchannel, the irregularly shaped microchannel being configured to cause a change in flow direction and / or velocity of fluid flowing through the irregularly shaped microchannel, thereby creating turbulence.

[0005] In some implementations, the irregular microchannel is a microchannel structure, and the equivalent diameter of the microchannel structure ranges from 10 μm to 3000 μm.

[0006] In some implementations, the hybrid layer includes a first accommodating cavity, the first accommodating cavity comprising: The first fluid inlet is connected to the upstream flow path; The first fluid outlet is connected to the irregularly shaped microchannel; The diversion structure is disposed within the first accommodating cavity, and the diversion structure is connected to both the first fluid inlet and the first fluid outlet.

[0007] In some implementations, a first retention cavity is formed between the diversion structure and the first fluid inlet.

[0008] In some implementations, a second retention cavity is formed between the diversion structure and the first fluid outlet.

[0009] In some implementations, the irregularly shaped microchannel includes: At least one fluid mixing unit, comprising: At least one flow section, said flow section being configured to allow fluid to pass through; And / or, At least one disturbance section is disposed upstream of the flow section, downstream of the flow section, or within the flow section, and the disturbance section is connected to the flow section, the disturbance section being configured to change the flow direction and / or flow velocity of the fluid.

[0010] In some implementations, the flow section is at least one of a straight line, a curve, a spiral, or a wave.

[0011] In some implementations, the perturbation segment includes at least one of the following structures: A variable diameter section is connected to the flow section, and the cross-sectional area of ​​the variable diameter section is different along the fluid flow direction. The variable diameter section is configured to cause a change in the flow velocity of the fluid by changing the cross-sectional area. A turning section is connected to the flow section, and the turning section includes at least a first section and a second section. The first section is disposed near the upstream side, and the second section is disposed near the downstream side. The extension directions of the first section and the second section are both intersecting the fluid flow direction. The included angle between the first section and the second section is an acute angle or a right angle. The turning section is configured to generate turbulence in the fluid by changing the fluid flow direction. A stop portion is connected to the flow section, and the extension direction of the stop portion intersects the fluid flow direction. The angle between the stop portion and the flow direction of the fluid before contacting the stop portion is a right angle or an obtuse angle. The stop portion is configured to cause a change in the flow direction and / or a change in the flow velocity of the fluid by obstructing the flow of the fluid. A cavity portion, connected to the flow section, and having a cavity, is configured to allow the fluid to diffuse and / or mix by providing a buffer space.

[0012] In some implementations, multiple fluid mixing units are provided, and the multiple fluid mixing units are connected in series and / or in parallel.

[0013] In some implementations, multiple irregularly shaped microchannels are provided, and the multiple irregularly shaped microchannels are connected in series and / or in parallel.

[0014] In some implementations, the diffusion layer further includes: A rectifier structure is disposed downstream of the irregular microchannel and is connected to the downstream flow path. The rectifier structure is configured to collect the fluid output from the irregular microchannel into a single flow path.

[0015] In some implementations, multiple mixing layers and multiple diffusion layers are provided, and the multiple mixing layers and multiple diffusion layers are arranged along the fluid flow direction.

[0016] In some implementations, the hybrid unit includes: A primary mixing layer and a secondary mixing layer are arranged along the fluid flow direction; The diffusion layer is disposed between the primary mixing layer and the secondary mixing layer.

[0017] Another aspect of this application provides a mixing module for a chromatography system, comprising: The housing includes a second fluid inlet and a second fluid outlet; As described above, the mixing unit is disposed inside the housing.

[0018] In some implementations, the housing includes: First shell; The second housing is disposed downstream of the first housing; A second accommodating cavity is formed between the first housing and the second housing, and the mixing unit is disposed within the second accommodating cavity; The upstream side of the first housing and the downstream side of the second housing are respectively connected to the pipeline of the chromatography system.

[0019] In some implementations, the outer casing includes a third housing, the third housing comprising: The mixing unit is disposed within the third accommodating cavity; The second fluid inlet and the second fluid outlet are respectively formed at both ends of the third housing, and one end of the third housing is configured to communicate with the instrument port of the chromatography system, and the other end of the third housing is configured to communicate with the pipeline of the chromatography system.

[0020] This application also provides a chromatographic analysis apparatus, comprising: The pump, injector, chromatographic column, and detector are arranged sequentially along the fluid flow direction; The hybrid module as described above; The mixing module is disposed between the injector and the chromatographic column, the second fluid inlet of the mixing module is connected to the injector, and the second fluid outlet of the mixing module is connected to the inlet of the chromatographic column. Alternatively, the mixing module may be disposed between the chromatographic column and the detector, with the second fluid inlet of the mixing module connected to the chromatographic column and the second fluid outlet of the mixing module connected to the detector.

[0021] This application further provides a method for suppressing solvent effects in a chromatographic system, comprising: A mixing module as described above is provided, the mixing module comprising a mixing layer and a diffusion layer arranged sequentially along the fluid flow direction, the mixing layer comprising a flow splitting structure, and the diffusion layer comprising irregularly shaped microchannels; The mixing module is connected between the six-way valve and the chromatographic column; In the separated state, the mobile phase carrying the sample flows through the mixing module; in the mixing layer, the flow-dividing structure disperses the fluid into multiple flow paths; in the diffusion layer, the irregularly shaped microchannels create turbulence in the fluid, thereby achieving premixing of the mobile phase and the sample. The technical solution provided in this application can achieve the following beneficial effects: The mixing unit provided in this application first disperses a single fluid stream into multiple flow paths through a flow-splitting structure, increasing the contact area between the sample solution and the mobile phase. This facilitates thorough mixing of the sample solution and the mobile phase, improving mixing efficiency. After being split by the flow-splitting structure, the fluid's direction or velocity is forcibly changed by the irregularly shaped microchannels in the diffusion layer, causing turbulence. This achieves molecular-level mixing of the sample solution and the mobile phase, increasing the mixing intensity between them and thus improving the accuracy of quantitative results in chromatographic and mass spectrometric analyses. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is an exploded structural diagram of a hybrid unit provided in an embodiment of this application; Figure 2 This is a cross-sectional schematic diagram of a hybrid unit provided in an embodiment of this application; Figure 3 This is a cross-sectional schematic diagram of a hybrid layer provided in an embodiment of this application; Figure 4 This is a schematic diagram of the structure of a first fluid mixing unit provided in an embodiment of this application, intended to illustrate the structure of a first flow section; Figure 5This is a schematic diagram of the structure of a first type of fluid mixing unit provided in an embodiment of this application, intended to illustrate the structure of a second type of flow section; Figure 6 This is a schematic diagram of the structure of a first type of fluid mixing unit provided in an embodiment of this application, intended to illustrate the structure of a third type of flow section; Figure 7 This is a schematic diagram of the structure of a second type of fluid mixing unit provided in an embodiment of this application, intended to illustrate the structure of the first type of disturbance section; Figure 8 This is a schematic diagram of the structure of a second type of fluid mixing unit provided in an embodiment of this application, intended to illustrate the structure of the second type of disturbance section; Figure 9 This is a schematic diagram of a third type of fluid mixing unit provided in an embodiment of this application; Figure 10 This is a schematic diagram of another structure of the third type of fluid mixing unit provided in an embodiment of this application; Figure 11 This is another structural schematic diagram of the third type of fluid mixing unit provided in an embodiment of this application; Figure 12 This is a schematic diagram of the diffusion layer provided in an embodiment of this application, intended to illustrate the rectification structure; Figure 13 This is a schematic diagram of the overall structure of a hybrid module provided in an embodiment of this application; Figure 14 This is a cross-sectional schematic diagram of a hybrid module provided in an embodiment of this application; Figure 15 This is a schematic diagram of the composition of a chromatographic analysis apparatus provided in one embodiment of this application; Figure 16 This is a schematic diagram of the composition of another chromatographic analysis apparatus provided in one embodiment of this application; Figure 17 This is a schematic diagram of the composition of another chromatographic analysis apparatus provided in an embodiment of this application; Figure 18 This is a schematic diagram of the separation state of a chromatographic analysis apparatus provided in an embodiment of this application; Figure 19 This is a schematic diagram of the sample loading state of a chromatographic analysis apparatus provided in an embodiment of this application; Figure 20 This is a chromatogram of a chromatographic analysis apparatus provided in an embodiment of this application without the mixing module installed; Figure 21 This is a chromatogram of a chromatographic analysis device provided in an embodiment of this application after the mixing module has been installed.

[0024] Explanation of reference numerals in the attached figures: 100. Mixing layer; 100a. Primary mixing layer; 100b. Secondary mixing layer; 101. Diverting structure; 102. Sleeve; 103. First receiving cavity; 104. First retention cavity; 105. Second retention cavity; 200. Diffusion layer; 201. Irregularly shaped microchannel; 2011. Fluid mixing unit; 2012. Flow section; 2013. Disturbance section; 2013a. Variable diameter section; 2013b. Directional section; 2013c. Stop section; 2013d. Cavity section; 202. Rectifying structure; 300, outer casing; 301, first casing; 302, second casing; 303, second accommodating cavity; 304, second fluid inlet; 305, second fluid outlet; 306, mixing unit; 400, Hybrid Module; 501. Solvent container; 502. Pump; 503. Mixer; 504. Injector; 505. Chromatographic column; 506. Detector; 507. Quantitative loop; 508. Six-way valve; 600, First fluid inlet; 601, First fluid outlet; 602, Third fluid inlet; 603, Third fluid outlet. Detailed Implementation

[0025] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of this application.

[0026] It should be noted that many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0027] In the description of this application, it should be understood that the terms "upper," "lower," "horizontal," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application 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, and therefore should not be construed as a limitation on this application. In this application, unless otherwise expressly specified and limited, the first feature being "upper" or "lower" than the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium.

[0028] In this application, unless otherwise expressly specified and limited, the terms "connected," "linked," and "fixed," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral unit; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. However, specifying a direct connection indicates that the two entities at the point of connection are not connected through a transitional structure, but are simply linked together to form a whole. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0029] In this application, the use of terms such as "first," "second," etc., is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of those features.

[0030] High-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS) are widely used analytical techniques in fields such as chemistry, biology, and medicine.

[0031] During analysis, samples typically need to be dissolved in a suitable sample solvent to form a sample solution, which is then introduced into the system via a syringe. However, in practice, samples are usually dissolved in strong solvents such as methanol, acetonitrile, and dimethyl sulfoxide (DMSO), while the mobile phase is usually a mixture of buffer salts and organic phases. This inherent mismatch between the sample solvent and the mobile phase in terms of strength, polarity, and pH inevitably leads to solvent effects.

[0032] In HPLC, the solvent effect manifests as follows: the sample cannot establish a proper partition equilibrium upon entering the column head, leading to peak leading-out, bifurcation, and tailing, thus reducing column efficiency, worsening resolution, and affecting the accuracy of quantitative results. In LC-MS, the solvent effect can also exacerbate ion suppression due to the instantaneous concentrated efflux of the sample, reducing mass spectrometry response and sensitivity, while also compromising electrospray stability and increasing baseline noise.

[0033] Existing technologies have attempted to mitigate the solvent effect by reducing injection volume, altering sample diluents, or increasing pre-column tubing volume. However, these methods either compromise analytical accuracy, increase development costs, or require instrument modifications, making it difficult to balance ease of operation with effective mixing. Therefore, how to efficiently and uniformly premix the sample solution and mobile phase without altering existing analytical methods and operating habits, thereby suppressing the solvent effect, is a pressing technical problem to be solved in this field.

[0034] To solve the above technical problems, refer to Figures 1 to 3As shown, one embodiment of this application provides a mixing unit applied to a chromatography system to suppress solvent effects and improve the accuracy and sensitivity of quantitative results.

[0035] In some embodiments, refer to Figure 1 and Figure 2 As shown, the mixing unit 306 may include at least one mixing layer 100. The mixing layer 100 may include at least one flow splitting structure 101. The flow splitting structure 101 is configured to disperse the fluid (including sample solvent and mobile phase) flowing into the mixing layer 100 into multiple flow paths.

[0036] It is understandable that by dispersing a single fluid stream into multiple flow paths through the flow splitting structure 101, the contact area between the sample solution and the mobile phase can be increased, so as to facilitate the thorough mixing of the sample solution and the mobile phase and improve the mixing efficiency.

[0037] In some specific embodiments, the flow splitting structure 101 can be configured as a single unit. When the properties of the sample solution and the mobile phase are relatively similar, the flow splitting of a single mixing layer 100 is sufficient to meet the mixing requirements.

[0038] In some specific embodiments, the splitting structure 101 can be configured in multiple ways (e.g., two, three or more). When the sample solution and the mobile phase have significantly different properties (e.g., pure methanol and pure water), or the injection volume is large (e.g., exceeding 20 μL), the sample solution and the mobile phase can be more thoroughly mixed initially by sequentially splitting the flow through multiple mixing layers 100.

[0039] It should be noted that the flow-diverting structure 101 can be implemented in various ways. In some specific embodiments, the flow-diverting structure 101 can take the form of a converging microchannel, that is, multiple channels or flow paths are processed on the mixing layer 100 by means of machining, laser engraving, or etching, so that the incoming fluid is dispersed into multiple paths through multiple channels and then re-converged downstream. In some specific embodiments, the flow-diverting structure 101 can take the form of a porous medium, such as particle stacking, powder sintering, or multilayer mesh structure stacking, forming multiple microchannels, and the fluid is naturally dispersed into multiple paths when passing through multiple microchannels.

[0040] In some embodiments, refer to Figure 1 and Figure 2 As shown, the mixing unit 306 may include at least one diffusion layer 200. At least one mixing layer 100 and at least one diffusion layer 200 are sequentially arranged along the fluid flow direction. At least one irregularly shaped microchannel 201 may be provided within the diffusion layer 200. This irregularly shaped microchannel 201 is configured to cause a change in the flow direction and / or velocity of the fluid flowing through it, thereby creating turbulence.

[0041] It is understandable that after the fluid is split by the mixing layer 100, the direction or velocity of the fluid is forcibly changed by the irregular microchannels 201 in the diffusion layer 200, causing the fluid to generate turbulence, thereby achieving molecular-level mixing of the sample solution and the mobile phase, suppressing the solvent effect, and thus improving the accuracy of quantitative results of chromatographic and mass spectrometric analysis.

[0042] In some specific embodiments, the irregularly shaped microchannel 201 can be configured as a single one. When the properties of the fluids to be mixed are relatively similar, or when the requirement for mixing uniformity is not high, a single diffusion layer 200 is sufficient.

[0043] In some specific embodiments, the irregularly shaped microchannels 201 can be configured in multiple ways (e.g., two, three or more). When the properties of the sample solution and the mobile phase differ significantly, or when extremely high mixing uniformity is required (e.g., for LC-MS analysis), multiple diffusion layers 200 can achieve more thorough turbulent mixing.

[0044] In some embodiments, refer to Figure 1 and Figure 2 As shown, the irregular microchannel 201 can be a microchannel structure. The equivalent diameter of the microchannel structure can range from 10 μm to 3000 μm.

[0045] It should be noted that the aforementioned equivalent diameter range (10 μm to 3000 μm) refers to the hydraulic diameter range of the main channel in the irregular microchannel 201 through which the fluid continuously passes. For local structures in the irregular microchannel 201 (such as the variable diameter section 2013a, cavity section 2013d, etc. described below), their local dimensions can be set according to the mixing requirements, and this application does not impose strict limitations on them.

[0046] It should also be noted that in chromatographic systems, the inner diameter of capillary columns is typically 50 μm to 500 μm, the inner diameter of microcolumns can reach 1 mm, and the inner diameter of conventional analytical columns is 2 mm to 5 mm. Therefore, the range of 10 μm to 3000 μm covers a wide range of applications from nanoflow chromatography and capillary chromatography to conventional analytical columns. In this application, the equivalent diameter of the microchannel structure can be 10 μm, 500 μm, 1000 μm, 1500 μm, 2000 μm, 2500 μm, or 3000 μm, etc., which will not be listed here. As long as it falls within the range of 10 μm to 3000 μm, it is within the scope of protection of this application.

[0047] This application does not impose specific limitations on the equivalent diameter of the microchannel structure. The equivalent diameter of the microchannel structure is set according to the actual mixing requirements (such as the degree of difference between the sample solution and the mobile phase, the injection volume, the system pressure, etc.) to ensure that the fluid can achieve the required mixing effect when flowing through the microchannel structure.

[0048] It is understandable that when the equivalent diameter of the microchannel structure ranges from 10 μm to 1000 μm, the fluid flowing through the microchannel structure is usually in a laminar flow state, which is beneficial for precise control of the direction and volume of the fluid, thereby improving the mixing intensity of the sample solution and the mobile phase, further suppressing the solvent effect, and improving the accuracy of quantitative results of chromatographic and mass spectrometric analysis.

[0049] In some embodiments, refer to Figure 1 and Figure 2 As shown, the mixing layer 100 may further include a ferrule 102. The ferrule 102 has a first receiving cavity 103. The first receiving cavity 103 includes a first fluid inlet 600 and a first fluid outlet 601. The first fluid inlet 600 is connected to an upstream flow path (such as a sample injector), and the first fluid outlet 601 is connected to the irregular microchannel 201. A flow splitting structure 101 is disposed within the first receiving cavity 103, and the flow splitting structure 101 is connected to both the first fluid inlet 600 and the first fluid outlet 601.

[0050] It is understandable that the first accommodating cavity 103 can encapsulate the flow splitting structure 101, thereby forming a stable connection between the flow splitting structure 101 and the upstream flow path and the downstream diffusion layer 200, which facilitates the integration and installation of the mixing unit 306.

[0051] It should be noted that the ferrule 102 can be made of corrosion-resistant materials such as stainless steel, titanium alloy, polyetheretherketone (PEEK) or polytetrafluoroethylene (PTFE) to adapt to the high-pressure environment of the chromatography system.

[0052] It should also be noted that the mixing layer in this embodiment can adopt various structures to achieve the diversion function. For example, the inner cavity of the mixing layer 100 itself can form a first receiving cavity 103, and the diversion structure 101 is disposed in the first receiving cavity 103. As another example, the diversion function can be achieved by the sleeve 102 of the above embodiment cooperating with the first receiving cavity 103.

[0053] In some embodiments, refer to Figure 1 and Figure 2 As shown, a first retention cavity 104 can be formed between the diversion structure 101 and the first fluid inlet 600.

[0054] Understandably, the first retention chamber 104, acting as a buffer zone, allows the fluid entering the mixing layer 100 to undergo preliminary diffusion and deceleration before contacting the flow splitting structure 101. This reduces the impact of the fluid on the flow splitting structure 101, preventing damage due to prolonged high-pressure impact; and it also ensures a relatively uniform velocity distribution before the fluid enters the flow splitting structure 101, thereby improving the uniformity of the flow splitting.

[0055] In some specific embodiments, the first retention cavity 104 can be configured as a cylindrical cavity, and the inner diameter of the first retention cavity 104 is larger than the inner diameter of the first fluid inlet 600. In this way, when fluid enters the wider first retention cavity 104 from the narrower first fluid inlet 600, the flow rate is reduced, forming a buffer.

[0056] In some specific embodiments, the first retention cavity 104 can be configured as a conical or spherical cavity to accommodate different fluid characteristics.

[0057] In some embodiments, refer to Figure 2 and Figure 3 As shown, a second retention cavity 105 can be formed between the diversion structure 101 and the first fluid outlet 601.

[0058] Understandably, the second retention chamber 105, acting as a buffer zone, allows the multiple flow paths dispersed by the diversion structure 101 to undergo preliminary convergence and mixing before entering the diffusion layer 200. This allows the multiple flow paths to collide, diffuse, and initially mix within the second retention chamber 105, pre-forming a relatively uniform fluid state before entering the diffusion layer 200, thereby reducing the mixing burden on the diffusion layer 200 and improving overall mixing efficiency.

[0059] In some specific embodiments, the second retention cavity 105 can be configured as a cylindrical cavity, and the inner diameter of the second retention cavity 105 is larger than the aperture of the output end of the flow splitting structure 101. In this way, after the multiple flow paths are output from the flow splitting structure 101, they can freely diffuse and collide within the second retention cavity 105, thereby achieving preliminary mixing.

[0060] In some specific embodiments, the second retention cavity 105 can be configured as a conical cavity, with the inner diameter of the second retention cavity 105 gradually decreasing along the fluid flow direction to guide the fluid smoothly into the diffusion layer 200.

[0061] In some embodiments, refer to Figures 4 to 11 As shown, the irregularly shaped microchannel 201 may include at least one fluid mixing unit 2011. The fluid mixing unit 2011 includes at least one flow section 2012 and at least one disturbance section 2013. The flow section 2012 is configured to allow fluid to pass through. The disturbance section 2013 is connected to the flow section 2012 and is configured to change the direction and / or velocity of the fluid.

[0062] Understandably, decomposing the irregularly shaped microchannel 201 into a combination of a flow section 2012 and a disturbance section 2013 allows for precise control of the fluid path. Thus, the flow section 2012 provides the basic channel for the fluid, while the disturbance section 2013 forcibly alters the fluid's motion state, allowing the flow section 2012 and disturbance section 2013 to work together to form an alternating pattern of flow, disturbance, and flow. This ensures that the fluid undergoes enhanced mixing as it flows through each disturbance section 2013, thereby improving the uniformity of mixing between the sample solution and the mobile phase.

[0063] In some specific embodiments, the disturbance section 2013 can be located upstream of the flow section 2012. That is, the fluid first flows through the disturbance section 2013 for mixing and enhancement, and then enters the flow section 2012 for transport, which is suitable for scenarios where rapid mixing is required before the fluid enters long-distance transport.

[0064] In some specific embodiments, the disturbance section 2013 can be located downstream of the flow section 2012. That is, the fluid first flows through the flow section 2012 for transport, and then enters the disturbance section 2013 for mixing enhancement, which is suitable for scenarios where the fluid needs to remain stable during transport and only mixes at the end.

[0065] In some specific embodiments, the disturbance section 2013 can be disposed in the flow section 2012. That is, the disturbance section 2013 is located in the middle of the flow section 2012. The disturbance section 2013 divides the flow section 2012 into an upstream section and a downstream section, and the fluid flows through the upstream section, the disturbance section 2013, and the downstream section in sequence, which is suitable for scenarios that require multi-stage mixing or compact layout.

[0066] It should be noted that this application does not impose strict restrictions on the location of the disturbance section 2013. The location of the disturbance section 2013 is set according to the actual mixing requirements (such as the degree of difference between the sample solution and the mobile phase, the injection volume, the system pressure, etc.) to ensure that the fluid can achieve the required mixing effect when flowing through the disturbance section 2013.

[0067] Reference Figures 4 to 11 As shown, the irregular microchannel 201 includes a third fluid inlet 602 and a third fluid outlet 603.

[0068] The third fluid inlet 602 is connected to the first fluid outlet 601. The position of the third fluid inlet 602 can be set according to the position of the first fluid outlet 601, and this application does not impose strict limitations on this. In some examples, the first fluid outlet 601 is located at the center of the mixing layer 100, and correspondingly, the third fluid inlet 602 is located at the center of the diffusion layer 200.

[0069] The third fluid outlet 603 is connected to the downstream flow path. The location of the third fluid outlet 603 can be set according to the configuration of the irregular microchannel 201 and the interface position of the downstream flow path; this application does not impose strict limitations on this. In some examples, the output end of the irregular microchannel 201 is a multi-stream flow path, and the third fluid outlet 603 can be located at the inlet of the rectifying structure 202. In some examples, the irregular microchannel 201 is a single-stream flow path, and the third fluid outlet 603 can be directly connected to the downstream pipeline.

[0070] In some specific embodiments, refer to Figures 4 to 6 As shown, the fluid mixing unit 2011 may include only the flow section 2012 and exclude the disturbance section 2013.

[0071] It is understandable that the fluid mixing unit 2011, which only includes the flow section 2012, is suitable for scenarios where only simple guidance of fluid direction is required and vigorous mixing is not necessary.

[0072] In some specific embodiments, refer to Figure 7 and Figure 8 As shown, the fluid mixing unit 2011 may include a flow section 2012 and a disturbance section 2013, forming a basic functional unit for flow and disturbance.

[0073] For example, refer to Figure 7 As shown, the fluid mixing unit 2011 may include a flow section 2012 and a disturbance section 2013, and the disturbance section 2013 may consist only of a variable diameter section 2013a. For example, see reference... Figure 8 As shown, the fluid mixing unit 2011 may include a flow section 2012 and a disturbance section 2013, and the disturbance section 2013 may include a variable diameter section 2013a, a turning section 2013b, a stop section 2013c and a cavity section 2013d.

[0074] In some embodiments, the flow section 2012 may be at least one of a straight line, a curve, a spiral, or a wave.

[0075] For example, refer to Figure 4 As shown, the flow section 2012 can be curved. For example, refer to... Figure 5 As shown, the flow section 2012 can be a combination of straight and curved shapes. For example, refer to... Figure 6 As shown, the flow section 2012 can be a combination of straight lines, curves, and waves.

[0076] It should be noted that the winding direction of the flow section 2012 can remain unchanged at all times (e.g., Figure 4 As shown, the flow section 2012 always coils in a clockwise direction), and the coiling direction of the flow section 2012 can also continuously change (e.g. Figure 5 As shown, the flow section 2012 first winds clockwise and then winds counterclockwise.

[0077] Understandably, the straight flow section 2012 maintains the fluid's velocity and direction, making it suitable for scenarios requiring rapid fluid transport. The curved flow section 2012 introduces bends in the flow channel, generating centrifugal force in the fluid and thus creating a velocity gradient before entering the disturbance section 2013. The spiral flow section 2012 extends the fluid path by looping, increasing the fluid's residence time in the mixing unit 306. The wavy flow section 2012, through continuous directional changes, causes the fluid to constantly change direction during flow, producing a slight mixing effect.

[0078] The various shapes of the flow sections 2012 can be selected according to actual needs. For example, a spiral flow section 2012 can be selected when a compact layout is required; a straight flow section 2012 can be selected when lower flow resistance is required.

[0079] In some embodiments, refer to Figure 7 and Figure 8 As shown, the disturbance section 2013 may include at least one of the following structures: a variable diameter section 2013a, a steering section 2013b, a stop section 2013c, or a cavity section 2013d.

[0080] The variable diameter section 2013a is connected to the flow section 2012, and the cross-sectional area of ​​the variable diameter section 2013a is different along the fluid flow direction. The variable diameter section 2013a is configured to cause the fluid to change its flow velocity by changing the cross-sectional area.

[0081] It is understandable that the variable diameter section 2013a can cause a change in fluid velocity through abrupt changes in the flow channel cross-section. That is, when fluid moves from a channel with a larger flow cross-sectional area to a channel with a smaller flow cross-sectional area, the flow velocity increases sharply; when fluid moves from a channel with a smaller flow cross-sectional area to a channel with a larger flow cross-sectional area, the flow velocity decreases sharply and eddies are generated. This disrupts the laminar flow state and promotes mixing. In some specific embodiments, the variable diameter section 2013a can be a Venturi structure where the flow channel diameter suddenly decreases and then gradually increases; in some specific embodiments, refer to... Figure 7 and Figure 8 As shown, the variable diameter section 2013a can be a diffusion structure with a sudden increase in the diameter of the flow channel.

[0082] The steering section 2013b is connected to the flow section 2012. The steering section 2013b includes at least a first section and a second section. The first section is disposed near the upstream side, and the second section is disposed near the downstream side. The extension directions of both the first and second sections intersect the fluid flow direction. The included angle between the first and second sections is an acute angle or a right angle. The steering section 2013b is configured to generate turbulence in the fluid by changing the fluid flow direction.

[0083] It is understood that the steering unit 2013b can induce turbulence in the fluid by changing its flow direction. That is, when the fluid is forced to change its flow direction within the steering unit 2013b, velocity differences arise within the fluid due to inertia, forming turbulence. In some specific embodiments, the steering unit 2013b can be a 90° right-angle bend. In some specific embodiments, refer to... Figure 8 As shown, the steering part 2013b can be a U-shaped bend. In some specific embodiments, the steering part 2013b can be an S-shaped bend. It should be noted that the angle and radius of curvature of the bend can be selected according to the required mixing intensity, and the embodiments of this application do not impose strict limitations on this.

[0084] The stop portion 2013c is connected to the flow section 2012, and the extension direction of the stop portion 2013c intersects the fluid flow direction. The angle between the stop portion 2013c and the flow direction of the fluid before contacting the stop portion 2013c is a right angle or an obtuse angle. The stop portion 2013c is configured to cause a change in the flow direction and / or a change in the flow velocity of the fluid by obstructing the flow of the fluid.

[0085] It is understood that the stop 2013c causes a change in the flow direction and / or velocity of the fluid by obstructing its flow. That is, the stop 2013c is disposed in the flow channel, and when the fluid encounters the stop 2013c, it is forced to flow around it, thereby forming a vortex region downstream of the stop 2013c. In some specific embodiments, refer to... Figure 8 As shown, the stop portion 2013c can be a plate-shaped baffle perpendicular to the flow channel direction, that is, the angle between the stop portion 2013c and the flow direction of the fluid before contacting the stop portion 2013c is a right angle. In some specific embodiments, the stop portion 2013c can be an inclined plate-shaped baffle, and the angle between the stop portion 2013c and the flow direction of the fluid before contacting the stop portion 2013c is an obtuse angle.

[0086] The cavity section 2013d is connected to the flow section 2012, and the cavity section 2013d has a cavity. The cavity section 2013d is configured to allow the fluid to diffuse and / or mix by providing a buffer space.

[0087] It is understood that the cavity portion 2013d can facilitate fluid diffusion and / or mixing by providing a buffer space. That is, when fluid enters the cavity with a larger flow cross-sectional area from a channel with a smaller flow cross-sectional area, the flow velocity decreases, and the fluid freely diffuses and collides within the cavity, achieving mixing. In some specific embodiments, the cavity of the cavity portion 2013d can be a spherical expansion cavity. In some specific embodiments, the cavity of the cavity portion 2013d can be a cylindrical buffer cavity. In some specific embodiments, refer to... Figure 8 As shown, the cavity of cavity part 2013d can be a polygonal hybrid cavity.

[0088] It should be noted that the above four types of disturbance section 2013 structures can be used individually or in combination. For example, a variable diameter section 2013a and a steering section 2013b can be simultaneously provided in a fluid mixing unit 2011 to achieve dual mixing enhancement.

[0089] It should also be noted that the equivalent diameters of the aforementioned variable diameter section 2013a, turning section 2013b, stop section 2013c, and cavity section 2013d can exceed the equivalent diameter range (10 μm to 3000 μm) of the main channel of the aforementioned microfluidic structure. For example, the cavity diameter of the cavity section 2013d can be greater than 3 mm, and the local expansion section of the variable diameter section 2013a can also be greater than 3 mm. The equivalent diameters of the variable diameter section 2013a, turning section 2013b, stop section 2013c, and cavity section 2013d are set according to the mixing requirements, as long as the variable diameter section 2013a, turning section 2013b, stop section 2013c, and cavity section 2013d can achieve the function of changing the fluid flow direction and / or flow velocity, and together with the main channel of the irregular microfluidic channel 201, constitute a complete irregular microfluidic channel 201.

[0090] In some specific embodiments, the fluid mixing unit 2011 may include multiple flow sections 2012 and multiple disturbance sections 2013, and the multiple flow sections 2012 and multiple disturbance sections 2013 are alternately arranged to achieve multi-stage mixing enhancement. For example, the fluid mixing unit 2011 includes, along the fluid flow direction, a flow section 2012, a disturbance section 2013, a flow section 2012, a disturbance section 2013, and a flow section 2012.

[0091] In some embodiments, refer to Figures 9 to 11 As shown, multiple fluid mixing units 2011 are provided. Multiple fluid mixing units 2011 can be connected in series and / or in parallel.

[0092] It should be noted that the fluid mixing unit 2011 refers to the basic unit constituting a single irregular microchannel 201, that is, the smallest functional unit composed of the flow section 2012 and the disturbance section 2013. The connection method between multiple fluid mixing units 2011 determines the internal structural layout of a single irregular microchannel 201.

[0093] In some specific embodiments, refer to Figure 9 As shown, multiple fluid mixing units 2011 are connected in series. That is, multiple fluid mixing units 2011 are arranged sequentially along the fluid flow direction, and the fluid flows through each fluid mixing unit 2011 in sequence. The series connection enables multi-stage mixing and is suitable for applications with extremely high requirements for mixing uniformity (such as LC-MS analysis). When extremely high mixing uniformity is required, three, four or more fluid mixing units 2011 can be connected in series, and this embodiment does not impose strict limitations on this.

[0094] In some specific embodiments, refer to Figure 10 and Figure 11 As shown, multiple fluid mixing units 2011 are arranged in parallel. That is, multiple fluid mixing units 2011 are arranged side-by-side in a plane perpendicular to the fluid flow direction, and fluid flows through multiple fluid mixing units 2011 simultaneously. Parallel arrangement can increase the mixing throughput per unit time, suitable for high-flow-rate processing scenarios. When processing large-volume samples (such as preparative liquid chromatography), two, three, or more fluid mixing units 2011 can be selected to be connected in parallel. Multiple parallel fluid mixing units 2011 can form a symmetrical or asymmetrical array structure on the surface of the diffusion layer 200, such as... Figure 10 As shown, multiple fluid mixing units 2011 are arranged side by side in a symmetrical manner; refer to Figure 11 As shown, multiple fluid mixing units 2011 are arranged side by side in an asymmetrical manner.

[0095] In some specific embodiments, the multiple fluid mixing units 2011 include both series and parallel structures. For example, multiple fluid mixing units 2011 are first connected in parallel to form a group, and then multiple groups are connected in series; or, for another example, multiple fluid mixing units 2011 are first connected in series to form a column, and then multiple columns are connected in parallel. In this way, both mixing uniformity and processing throughput can be taken into account, making it suitable for application scenarios with high requirements for both mixing uniformity and processing throughput.

[0096] In some embodiments, refer to Figure 1 and Figure 2As shown, multiple irregularly shaped microchannels 201 are provided, and these microchannels 201 are connected in series and / or in parallel. It should be noted that each irregularly shaped microchannel 201 refers to an independent channel with complete mixing function, and each microchannel 201 may contain one or more fluid mixing units 2011. The connection method between the multiple irregularly shaped microchannels 201 determines the overall structural layout of the diffusion layer 200.

[0097] In some specific embodiments, multiple irregularly shaped microchannels 201 are arranged in series. That is, multiple irregularly shaped microchannels 201 are arranged sequentially along the fluid flow direction, and the fluid flows through each irregularly shaped microchannel 201 in sequence. The series arrangement enables multi-stage mixing and is suitable for applications with extremely high requirements for mixing uniformity (such as trace analysis). When extremely high mixing uniformity is required, three, four or more irregularly shaped microchannels 201 can be selected to be connected in series, and this application embodiment does not impose strict limitations on this.

[0098] In some specific embodiments, multiple irregularly shaped microchannels 201 are arranged in parallel. That is, multiple irregularly shaped microchannels 201 are arranged side by side in a plane perpendicular to the fluid flow direction, and the fluid flows through multiple irregularly shaped microchannels 201 simultaneously. Parallel arrangement can improve mixing throughput and is suitable for high-flow-rate processing scenarios. When processing large-volume samples (such as preparative liquid chromatography), two, three or more irregularly shaped microchannels 201 can be selected to be connected in parallel.

[0099] In some specific embodiments, the multiple irregularly shaped microchannels 201 include both series and parallel structures. For example, multiple irregularly shaped microchannels 201 are first connected in parallel to form a group, and then multiple groups are connected in series; or, for another example, multiple irregularly shaped microchannels 201 are first connected in series to form a column, and then multiple columns are connected in parallel. In this way, the multiple irregularly shaped microchannels 201 are configured in a series-parallel combination, which can take into account both mixing uniformity and processing throughput, and is suitable for a variety of application scenarios.

[0100] In some embodiments, refer to Figure 2 and Figure 12 As shown, the diffusion layer 200 may further include a rectifying structure 202. The rectifying structure 202 is disposed downstream of the irregular microchannel 201 and is connected to the downstream flow path. The rectifying structure 202 is configured to collect the fluid output from the irregular microchannel 201 near the downstream flow path into a single flow path.

[0101] It is understandable that after mixing in the irregular microchannel 201, the fluid may exist in the form of multiple flow paths. By using the rectifying structure 202 to collect the fluid output from the irregular microchannel 201 into a single flow path, the fluid can enter the downstream flow path with a stable flow pattern, while reducing the dead volume caused by the dispersion of flow paths.

[0102] In some specific embodiments, the rectifier structure 202 can be a tapered constriction channel, with the inner diameter of the rectifier structure 202 gradually decreasing along the fluid flow direction to guide and merge multiple flow paths.

[0103] In some specific embodiments, the rectifier structure 202 can be an end cap with a guide groove, which guides multiple flow paths to the central outlet, thereby achieving the guiding and merging of multiple flow paths.

[0104] In some specific embodiments, refer to Figure 12 As shown, the rectifier structure 202 can be a single outlet structure formed by the convergence of multiple micro-channels, realizing the guidance and convergence of multiple flow paths.

[0105] In some embodiments, refer to Figure 1 and Figure 2 As shown, multiple mixing layers 100 and multiple diffusion layers 200 are provided, and the multiple mixing layers 100 and multiple diffusion layers 200 are arranged along the fluid flow direction.

[0106] In some embodiments, the plurality of mixing layers 100 and the plurality of diffusion layers 200 can be arranged in various orders along the fluid flow direction. For example, the plurality of mixing layers 100 can be arranged continuously to form a mixing layer group, and the plurality of diffusion layers 200 can be arranged continuously to form a diffusion layer group, with the mixing layer group and the diffusion layer group arranged sequentially along the fluid flow direction. As another example, the mixing layer 100 and the diffusion layer 200 can be arranged in any order, as long as it is ensured that the fluid is fully mixed after flowing through all the mixing layers 100 and diffusion layers 200. The appropriate arrangement is selected according to actual mixing requirements (such as the degree of difference between the sample solvent and the mobile phase, the injection volume, the system pressure, etc.), and the embodiments of this application do not impose strict limitations on this.

[0107] In some specific embodiments, along the fluid flow direction, the mixing unit 306 may sequentially include a mixing layer 100, a diffusion layer 200, another mixing layer 100, and a diffusion layer 200 to achieve multi-stage mixing of splitting, turbulence, re-splitting, and re-turbulence. It is understood that with each combination of the mixing layer 100 and the diffusion layer 200, the degree of mixing between the sample solution and the mobile phase is further improved.

[0108] Thus, when the properties of the sample solvent and the mobile phase are very different (such as pure DMSO and pure water), or when extremely high mixing uniformity is required (such as trace analysis), two, three or more sets of alternating mixing layers 100 and diffusion layers 200 can be selected.

[0109] In some embodiments, refer to Figure 1 As shown, the mixing layer 100 includes a primary mixing layer 100a and a secondary mixing layer 100b disposed along the fluid flow direction. A diffusion layer 200 is disposed between the primary mixing layer 100a and the secondary mixing layer 100b.

[0110] Understandably, the primary mixing layer 100a first splits the fluid, increasing the contact area; the fluid then enters the diffusion layer 200, where turbulence is generated through the irregularly shaped microchannels 201, achieving molecular-level mixing of the sample solution and the mobile phase; finally, it enters the secondary mixing layer 100b for a second split, further homogenizing the fluid. In this way, a complete mixing process of splitting, turbulence, and re-splitting can be achieved within a compact space, resulting in high mixing efficiency and small volume, making it particularly suitable for integration into the tubing of a chromatography system.

[0111] In some specific embodiments, the primary mixing layer 100a and the secondary mixing layer 100b may have the same structure. In this way, the primary mixing layer 100a and the secondary mixing layer 100b form a symmetrical structure, which facilitates manufacturing and assembly, and at the same time enables a uniform flow distribution effect.

[0112] Another embodiment of this application provides a mixing module 400 for a chromatography system. (See also...) Figure 13 and Figure 14 As shown, the hybrid module 400 may include a hybrid unit 306 as described in any of the above embodiments.

[0113] In some embodiments, refer to Figure 13 and Figure 14 As shown, the hybrid module 400 may further include a housing 300 to provide a standardized interface for easy installation and replacement. The hybrid unit 306 is disposed inside the housing 300 for encapsulation and protection.

[0114] In some embodiments, refer to Figure 13 and Figure 14 As shown, the housing 300 may have a second fluid inlet 304 and a second fluid outlet 305. The second fluid inlet 304 is for connection to an upstream pipeline in the chromatography system. The second fluid outlet 305 is for connection to a downstream pipeline in the chromatography system.

[0115] It should be noted that the interface type of the second fluid inlet 304 and the second fluid outlet 305 can be selected according to the piping type of the chromatography system. In some specific embodiments, both the second fluid inlet 304 and the second fluid outlet 305 can be internally threaded interfaces for connection with the standard pipeline connectors of the chromatography system. In some specific embodiments, both the second fluid inlet 304 and the second fluid outlet 305 can be standard connectors with pipelines for direct insertion into the piping of the chromatography system.

[0116] In some embodiments, refer to Figure 13 and Figure 14As shown, the outer casing 300 may include a first casing 301 and a second casing 302 disposed downstream of the first casing 301. A second accommodating cavity 303 is formed between the first casing 301 and the second casing 302, and the mixing unit 306 is disposed within the second accommodating cavity 303. The upstream side of the first casing 301 and the downstream side of the second casing 302 are respectively connected to the piping of the chromatography system.

[0117] It should be noted that the first housing 301 and the second housing 302 can be fixedly connected by means of threaded connection, snap-fit ​​or welding, so as to facilitate the installation and maintenance of the mixing unit 306.

[0118] In some specific embodiments, the first housing 301 and the second housing 302 may be connected by threads to facilitate the disassembly and replacement of the mixing unit 306. In some specific embodiments, the first housing 301 and the second housing 302 may be connected by an interference fit, resulting in a compact structure.

[0119] In some embodiments, the housing 300 may include a third housing. The third housing may include a third accommodating cavity. The mixing unit 306 is disposed within the third accommodating cavity. A second fluid inlet 304 and a second fluid outlet 305 are respectively formed at both ends of the third housing. One end of the third housing is configured to communicate with the instrument port of the chromatography system, and the other end of the third housing is configured to communicate with the tubing of the chromatography system.

[0120] In some specific embodiments, one end of the third housing may be provided with a threaded structure for direct threaded connection to the instrument port of the chromatography system (such as the injector interface or column interface). In this way, the mixing module 400 can be directly installed on the instrument port without the need for additional adapter piping, resulting in a compact structure and convenient installation.

[0121] It should be noted that this application does not impose strict limitations on the specific structure of the third housing, as long as it can encapsulate the mixing unit 306 and provide a second fluid inlet 304 and a second fluid outlet 305. A suitable housing structure can be selected based on actual installation requirements (such as the interface type of the instrument port, space constraints, etc.). It is understood that when one end of the third housing is configured to connect directly to the instrument port in the chromatography system, additional adapter piping can be eliminated, improving the structural compactness of the chromatography system.

[0122] This application provides another aspect of a chromatographic analysis apparatus. (Refer to...) Figures 15 to 17 As shown, the chromatographic analysis device includes a pump 502, an injector 504, a chromatographic column 505 and a detector 506 arranged sequentially along the fluid flow direction, as well as a mixing module 400 as described in any of the above embodiments.

[0123] In some specific embodiments, the chromatographic analysis apparatus may be a liquid chromatography system. This liquid chromatography system includes a solvent container 501, a pump 502, a mixer 503, an injector 504, a chromatographic column 505, and a detector 506, arranged sequentially along the flow direction of the fluid to be detected. A mixing module 400 may be disposed between the injector 504 and the chromatographic column 505, or between the chromatographic column 505 and the detector 506, or between the injector 504 and the chromatographic column 505 and the detector 506, to suppress solvent effects.

[0124] It should be noted that the solvent container 501 is used to store the mobile phase. The pump 502 is used to drive the mobile phase to be delivered stably at high pressure. The mixer 503 is used to mix solvents of different proportions to form the desired mobile phase. The sample is dissolved in a suitable sample solvent to form a sample solution. The injector 504 is used to introduce the sample solution into the mobile phase flow path. The chromatographic column 505 is used to separate the components in the sample, and the detector 506 is used to detect the separated components. It is understood that the mixing module 400 provided in this application can be integrated into the above-mentioned chromatographic flow path to mix the sample solution and the mobile phase before or after entering the chromatographic column 505, so as to suppress the solvent effect.

[0125] It should be noted that when the mixing module 400 is integrated into the chromatographic flow path, the system presents two working states by switching the valve position of the injector 504.

[0126] Specifically, in some embodiments, reference is made to Figure 18 and Figure 19 As shown, the chromatographic analysis apparatus may also include a six-way valve 508 (or injection switching valve). The six-way valve 508 has six ports (ports a to f) arranged circumferentially, and a valve core that can switch between sample loading and separation states. A mixing module 400 is disposed between the six-way valve 508 and the chromatographic column 505, and is connected in series with the quantitative loop 507. It is used to premix the sample solution and mobile phase before the fluid enters the chromatographic column 505, reducing the influence of solvent effects on the analytical results.

[0127] Reference Figure 18 As shown, the system is initially in a disconnected state. Port a of the six-way valve 508 is connected to port f, port b is connected to port c, and port d is connected to port e.

[0128] The mobile phase flows out from pump 502, passes through port c and port b in sequence, enters the quantitative loop 507, then passes through port e and port d in sequence into the mixing module 400, and then flows into the chromatographic column 505 and detector 506 in sequence. At this time, the quantitative loop 507 is filled with mobile phase, and only mobile phase flows through the mixing module 400, and the system is in equilibrium.

[0129] Reference Figure 19 As shown, the six-way valve 508 is switched to the sample loading state: port a is connected to port b, port c is connected to port d, and port e is connected to port f.

[0130] The sample solution flows out from the injector 504 and sequentially enters the metering loop 507 through interface a and interface b. The original mobile phase in the metering loop 507 is pushed out by the sample solution and discharged into the waste liquid through interface e and interface f. The injection ends when the metering loop 507 is filled with the sample solution.

[0131] At this point, the mobile phase flows out of pump 502, sequentially through interface c and interface d into mixing module 400, and then sequentially through chromatographic column 505 to detector 506. Only the mobile phase flows through mixing module 400, maintaining stable system pressure.

[0132] Reference Figure 18 As shown, the six-way valve 508 switches back to the disconnected state. Port a of the six-way valve 508 is connected to port f, port b is connected to port c, and port d is connected to port e.

[0133] The mobile phase flows out of pump 502 and sequentially enters metering loop 507 through interface c and interface b, pushing the sample solution in metering loop 507 sequentially through interface e and interface d into mixing module 400. The sample solution and mobile phase are initially mixed at the outlet of metering loop 507, and then both enter mixing module 400 through interface d.

[0134] Within the mixing module 400, the sample solution and the mobile phase flow sequentially through the mixing layer 100 and the diffusion layer 200: In the mixing layer 100, the flow splitting structure 101 disperses the fluid into multiple flow paths, increasing the contact area between the sample solution and the mobile phase; In the diffusion layer 200, the irregularly shaped microchannels 201 change the direction and velocity of the fluid flow, generating turbulence and achieving molecular-level mixing of the sample solution and the mobile phase.

[0135] The homogeneous fluid flows out from the mixing module 400 and enters the chromatographic column 505 for separation. At this point, since the sample solution and mobile phase have been homogeneously mixed before entering the chromatographic column 505, the solvent effect is suppressed, thereby obtaining symmetrical and sharp chromatographic peaks and improving the resolution.

[0136] Understandably, in traditional chromatographic analysis devices, the six-way valve 508 is directly connected to the chromatographic column 505, and the sample solution and mobile phase are passively mixed only at the head of the chromatographic column 505. Due to the differences between the sample solvent and the mobile phase in terms of strength, polarity, pH value, etc., solvent effect is easily generated, which leads to chromatographic peak shape distortion, decreased column efficiency, and poor resolution. In LC-MS system, it will also aggravate ion suppression and reduce detection sensitivity.

[0137] This embodiment of the application incorporates a mixing module 400 between the six-way valve 508 and the chromatographic column 505, enabling pre-mixing of the sample solution and mobile phase before they enter the column 505. In the separation state, the mobile phase carries the sample through the mixing module 400, resulting in homogeneous mixing of the sample solution and mobile phase. This reduces the property differences between the sample solvent and the mobile phase, establishing a normal distribution equilibrium in the column 505, yielding symmetrical and sharp chromatographic peaks, and improving column efficiency and resolution. Furthermore, the further mixing of the mobile phase in the separation state via the mixing module 400 leads to a more homogeneous and stable composition, making it particularly suitable for LC-MS systems. This improves the stability of electrospray ionization, reduces baseline noise, and enhances detection sensitivity. Additionally, the mixing module 400 provided in this embodiment is ready to use immediately, requiring no changes to existing chromatographic analysis methods and operating habits, incurring no additional development costs, and not affecting instrument calibration, thus possessing broad applicability.

[0138] In some embodiments, refer to Figure 15 As shown, the mixing module 400 can be disposed between the injector 504 and the chromatographic column 505. The second fluid inlet 304 of the mixing module 400 is connected to the injector 504, and the second fluid outlet 305 of the mixing module 400 is connected to the chromatographic column 505.

[0139] Specifically, the sample solution and mobile phase are premixed before entering the chromatographic column 505. Through the split-flow turbulence of the mixing module 400, the sample solution and mobile phase are forcibly mixed uniformly, eliminating differences in strength, polarity, and pH between the sample solvent and the mobile phase. When the uniformly mixed fluid enters the chromatographic column 505, the sample can establish a normal partition equilibrium, resulting in symmetrical, sharp chromatographic peaks with stable retention times and improved resolution.

[0140] Understandably, for HPLC systems, pre-column installation is crucial for resolving peak shape issues. For LC-MS systems, pre-column installation not only improves peak shape but also provides stable injection conditions for mass spectrometry detection by stabilizing the composition of the mobile phase effluent from column 505.

[0141] In some embodiments, refer to Figure 16 As shown, the mixing module 400 can be disposed between the chromatographic column 505 and the detector 506. The second fluid inlet 304 of the mixing module 400 is connected to the chromatographic column 505, and the second fluid outlet 305 of the mixing module 400 is connected to the detector 506.

[0142] Specifically, in LC-MS analysis, the mobile phase undergoes electrospray ionization after entering the mass spectrometer nozzle. If the mobile phase composition is unstable (e.g., rapid changes in the organic phase ratio during the later stages of gradient elution), it can lead to spray instability, increased baseline noise, and signal fluctuations. By installing a post-column mixing module 400, the mobile phase can be further mixed, resulting in a more homogeneous composition and more stable spray, thereby improving detection sensitivity and signal stability.

[0143] In some embodiments, refer to Figure 17 As shown, a mixing module 400 can be installed between the injector 504 and the chromatographic column 505, and another mixing module 400 can be installed between the chromatographic column 505 and the detector 506. This achieves the dual benefits of improved peak shape and stable signal.

[0144] It should be noted that in practical applications, the position of the hybrid module 400 can be flexibly selected according to the requirements, and this application embodiment does not impose strict restrictions on this.

[0145] Liquid chromatography analysis methods include the following steps: S1. Dissolve the sample in a suitable sample solvent to form a sample solution; S2. Adjust the system to a separation state, so that the mobile phase fills the entire flow path of the chromatographic system (including quantitative loop 507, chromatographic column 505 and detector 506), and the system is in equilibrium. S3. Switch the system to sample loading mode so that the sample solution fills the quantitative loop 507. At this time, the mobile phase does not pass through the quantitative loop 507 and flows directly to the chromatographic column 505 to maintain the stability of the system pressure. S4. Switch the system back to separation mode. The mobile phase enters the quantitative loop 507 and pushes the sample solution in the quantitative loop 507. The sample solution flows sequentially through the chromatographic column 505 and the detector 506 under the carrying of the mobile phase, thereby realizing the separation and detection of sample components.

[0146] In the methods described above, the inherent mismatch between the sample solvent (e.g., pure methanol) and the mobile phase (e.g., 20% methanol aqueous solution) in terms of strength, polarity, and pH inevitably leads to solvent effects. Specifically, when the sample solution enters the column head, the strong solvent temporarily and locally alters the column head's elution capacity, causing weakly retained components in the sample to be prematurely elute. This results in peak forwarding, bifurcation, and tailing, affecting the effectiveness of chromatographic separation and the accuracy of quantitative results.

[0147] To suppress the aforementioned solvent effect, this application further provides a method for suppressing the solvent effect in a chromatographic system, the method being applied in step S4 (i.e., before the sample is carried into the chromatographic column 505 by the mobile phase). The method includes: Step S41: Provide a mixing module 400 as described in any of the above embodiments. The mixing module 400 includes a mixing layer 100 and a diffusion layer 200 arranged sequentially along the fluid flow direction. The mixing layer 100 includes a flow splitting structure 101, and the diffusion layer 200 includes a shaped microchannel 201. Step S42: Connect the mixing module 400 between the six-way valve and the chromatographic column 505 (i.e., connect it in series between the outlet of the quantitative loop 507 and the inlet of the chromatographic column 505). Step S43: In the separated state, the mobile phase carrying the sample flows through the mixing module 400. Specifically, in the mixing layer 100, the flow splitting structure 101 disperses the fluid into multiple flow paths, increasing the contact area between the sample and the mobile phase. In the diffusion layer 200, the irregularly shaped microchannels 201 generate turbulence in the fluid, achieving molecular-level mixing of the sample solvent and the mobile phase. The premixed fluid then enters the chromatographic column 505 for separation.

[0148] By using the above method, the sample solution and the mobile phase are mixed evenly before entering the chromatographic column 505, eliminating the differences in strength, polarity, and pH between the sample solvent and the mobile phase. This allows a normal distribution equilibrium to be established at the head of the chromatographic column 505, resulting in symmetrical and sharp chromatographic peaks and improving column efficiency and resolution.

[0149] To verify the effect of the mixing module 400 in eliminating the solvent effect in the embodiments of this application, a comparative experiment was conducted.

[0150] The experimental conditions are as follows: Chromatographic conditions: mobile phase was 20% (v / v) methanol aqueous solution; flow rate was 1 mL / min; detection wavelength was 265 nm; chromatographic column was YMC Triart C18 (5 μm, 250 × 4.6 mm).

[0151] Sample: Methanol solution of 80 μg / mL syringin; Injection volume: 16 μL.

[0152] Experimental results: Reference Figure 20 As shown (without the mixing module 400 in this embodiment), a significant solvent effect occurs due to the mismatch in strength between the sample solvent (methanol) and the initial mobile phase (20% methanol), manifested as the target analyte chromatographic peak shape (see...). Figure 20 (As shown by the middle arrow a) Severe forward extension, bifurcation, and peak distortion severely affect the accuracy of qualitative and quantitative analysis.

[0153] Reference Figure 21 (A mixing module 400 according to this embodiment is provided between the injector 504 and the chromatographic column 505), under the same conditions, the chromatographic peak shape (see...) Figure 21As shown by arrow b), the results are significantly improved. The peak shape is symmetrical and sharp, and the leading-out and bifurcation phenomena are basically eliminated. This indicates that the mixing module 400 of this application embodiment efficiently premixes the sample solvent and mobile phase, effectively eliminating the negative impact of the solvent effect and ensuring the effectiveness of chromatographic separation and the reliability of quantitative results.

[0154] The above detailed embodiments further illustrate the purpose, technical solutions, and beneficial effects of the embodiments of this application. It should be understood that the above are merely specific embodiments of the embodiments of this application and are not intended to limit the scope of protection of the embodiments of this application. Any modifications, equivalent substitutions, improvements, etc., made on the basis of the technical solutions of the embodiments of this application should be included within the scope of protection of the embodiments of this application.

Claims

1. A mixing unit for use in a chromatographic system, characterized in that, include: At least one mixing layer (100) and at least one diffusion layer (200) are sequentially arranged along the fluid flow direction. The hybrid layer (100) includes: At least one flow splitting structure (101) is configured to disperse the fluid flowing into the mixing layer (100) into multiple flow paths; The diffusion layer (200) includes: At least one irregularly shaped microchannel (201) is configured to cause a change in flow direction and / or velocity of fluid flowing through the irregularly shaped microchannel (201) to form turbulence.

2. The hybrid unit according to claim 1, characterized in that, The irregular microchannel (201) is a microchannel structure, and the equivalent diameter of the microchannel structure ranges from 10 μm to 3000 μm.

3. The hybrid unit according to claim 1, characterized in that, The mixing layer (100) includes a first receiving cavity (103), the first receiving cavity (103) comprising: The first fluid inlet (600) is connected to the upstream flow path; The first fluid outlet (601) is connected to the irregular microchannel (201); The diversion structure (101) is disposed in the first accommodating cavity (103), and the diversion structure (101) is connected to both the first fluid inlet (600) and the first fluid outlet (601).

4. The hybrid unit according to claim 3, characterized in that, A first retention cavity (104) is formed between the diversion structure (101) and the first fluid inlet (600).

5. The hybrid unit according to claim 3, characterized in that, A second retention cavity (105) is formed between the diversion structure (101) and the first fluid outlet (601).

6. The hybrid unit according to claim 1, characterized in that, The irregularly shaped microchannel (201) includes: At least one fluid mixing unit (2011) includes: At least one flow section (2012) is configured to allow fluid to pass through; And / or, At least one disturbance section (2013) is disposed on the upstream side, the downstream side, or within the flow section (2012), and the disturbance section (2013) is connected to the flow section (2012), the disturbance section (2013) being configured to change the flow direction and / or flow velocity of the fluid.

7. The hybrid unit according to claim 6, characterized in that, The flow section (2012) is at least one of a straight line, a curve, a spiral, or a wave.

8. The hybrid unit according to claim 6, characterized in that, The disturbance segment (2013) includes at least one of the following structures: A variable diameter section (2013a) is connected to the flow section (2012), and the cross-sectional area of ​​the variable diameter section (2013a) is different along the fluid flow direction. The variable diameter section (2013a) is configured to cause a change in the flow velocity of the fluid by changing the cross-sectional area. A turning section (2013b) is connected to the flow section (2012), and the turning section (2013b) includes at least a first section and a second section. The first section is disposed near the upstream side, and the second section is disposed near the downstream side. The extension directions of the first section and the second section are both intersecting the fluid flow direction. The included angle between the first section and the second section is an acute angle or a right angle. The turning section (2013b) is configured to generate turbulence in the fluid by changing the fluid flow direction. A stop (2013c) is connected to the flow section (2012), and the extension direction of the stop (2013c) intersects the fluid flow direction. The angle between the stop (2013c) and the flow direction of the fluid before contacting the stop (2013c) is a right angle or an obtuse angle. The stop (2013c) is configured to cause a change in the flow direction and / or a change in the flow velocity of the fluid by obstructing the flow of the fluid. The cavity section (2013d) is connected to the flow section (2012) and has a cavity, the cavity section (2013d) being configured to allow the fluid to diffuse and / or mix by providing a buffer space.

9. The hybrid unit according to claim 6, characterized in that, Multiple fluid mixing units (2011) are provided, and the multiple fluid mixing units (2011) are connected in series and / or in parallel.

10. The hybrid unit according to claim 1, characterized in that, Multiple irregularly shaped microchannels (201) are provided, and the multiple irregularly shaped microchannels (201) are connected in series and / or in parallel.

11. The hybrid unit according to claim 1, characterized in that, The diffusion layer (200) further includes: A rectifier structure (202) is disposed downstream of the irregular microchannel (201) and is connected to the downstream flow path. The rectifier structure (202) is configured to collect the fluid output from the irregular microchannel (201) into a single flow path.

12. The hybrid unit according to claim 1, characterized in that, Multiple mixing layers (100) and multiple diffusion layers (200) are provided, and the multiple mixing layers (100) and multiple diffusion layers (200) are arranged along the fluid flow direction.

13. The hybrid unit according to claim 1, characterized in that, The mixing unit includes: A primary mixing layer (100a) and a secondary mixing layer (100b) are disposed along the fluid flow direction; wherein, the diffusion layer (200) is disposed between the primary mixing layer (100a) and the secondary mixing layer (100b).

14. A mixing module for a chromatography system, characterized in that, include: The housing (300) includes a second fluid inlet (304) and a second fluid outlet (305); The mixing unit (306) as claimed in any one of claims 1 to 13 is disposed inside the housing (300).

15. The hybrid module according to claim 14, characterized in that, The housing (300) includes: First housing (301); The second housing (302) is disposed downstream of the first housing (301); A second accommodating cavity (303) is formed between the first housing (301) and the second housing (302), and the mixing unit (306) is disposed in the second accommodating cavity (303); The upstream side of the first housing (301) and the downstream side of the second housing (302) are respectively connected to the pipeline of the chromatography system.

16. The hybrid module according to claim 14, characterized in that, The outer casing (300) includes a third casing, the third casing comprising: The mixing unit (306) is disposed in the third accommodating cavity; The second fluid inlet (304) and the second fluid outlet (305) are respectively formed at both ends of the third housing, and one end of the third housing is configured to communicate with the instrument port of the chromatography system, and the other end of the third housing is configured to communicate with the pipeline of the chromatography system.

17. A chromatographic analysis apparatus, characterized in that, include: The pump (502), injector (504), chromatographic column (505) and detector (506) are arranged sequentially along the fluid flow direction. The hybrid module (400) as described in any one of claims 14 to 16. The mixing module (400) is disposed between the injector (504) and the chromatographic column (505), the second fluid inlet (304) of the mixing module (400) is connected to the injector (504), and the second fluid outlet (305) of the mixing module (400) is connected to the inlet of the chromatographic column (505). Alternatively, the mixing module (400) is disposed between the chromatographic column (505) and the detector (506), with the second fluid inlet (304) of the mixing module (400) connected to the chromatographic column (505) and the second fluid outlet (305) of the mixing module (400) connected to the detector (506).

18. A method for suppressing solvent effects in a chromatographic system, characterized in that, include: A mixing module (400) as described in any one of claims 14 to 16 is provided, the mixing module (400) comprising a mixing layer (100) and a diffusion layer (200) arranged sequentially along the fluid flow direction, the mixing layer (100) comprising a flow splitting structure (101), and the diffusion layer (200) comprising a shaped microchannel (201). The mixing module (400) is connected between the six-way valve (508) and the chromatographic column (505); In the separated state, the mobile phase carries the sample and flows together through the mixing module (400); in the mixing layer (100), the flow splitting structure (101) disperses the fluid into multiple flow paths; in the diffusion layer (200), the irregular microchannel (201) causes the fluid to form turbulence, thereby realizing the premixing of the mobile phase and the sample.

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