System and probe for rotary in-situ preparation of polymer coating capillary tube and application of system and probe

Abstract

The invention discloses a system and a probe for rotary in-situ preparation of a polymer coating capillary tube and application of the system and the probe, and belongs to the technical field of rapid sample extraction and analysis. The system comprises: a surface activation treatment module, which is used for forming a pre-modification layer on the inner surface of a capillary substrate through a bifunctional grafting reagent; the local ablation module is used for carrying out patterning treatment on the pre-modification layer through an electric heating or laser mask technology; the rotary polymerization module is used for driving the capillary tube to rotate around the axis and exciting in-situ polymerization reaction of the monomer solution; and the control module is used for controlling polymerization reaction conditions and generating a polymer in-situ growth layer with adjustable porosity. The probe is composed of a capillary base body and a polymer in-situ growth layer, a coating on the inner surface of the probe has axial uniformity and multi-segment patterning characteristics, and the probe is suitable for in-situ extraction detection of small-size biological samples such as whole blood, plasma and urine. The rotary parameterization control of the coating thickness and the porosity is realized, various chemical derivatization methods are compatible, and the detection sensitivity is remarkably improved.

Description

Technical Field

[0001] The invention relates to the technical field of solid phase extraction analysis, and in particular to a system for preparing a polymer coating capillary in situ by rotation, and a method for preparing a probe for rapid extraction, in situ ionization and photoderivation reaction by using the system. Background Art When analyzing organic components in samples with complex components such as biological tissues and environmental samples, due to the complexity of the sample composition, sufficient pretreatment of the obtained samples is an essential step; first subjecting the samples to liquid-liquid extraction, then using liquid chromatography for separation, and finally analyzing by mass spectrometry has become the industry's gold standard. The currently commonly used liquid-liquid extraction method has a complex operating process, is time-consuming, and will introduce reagents such as chloroform that are seriously polluting and toxic. There is also a considerable loss of samples during repeated transfers. Liquid chromatography also has shortcomings such as high operating costs and long separation times. Rapid sampling extraction and in-situ ionization technology have significant advantages in this field. This type of technology can not only save time and human resources, and improve the convenience and timeliness of detection, but also reduce dependence on large amounts of organic solvents, thereby reducing the pollution burden on the environment.

[0002] In response to the above problems, researchers have developed many methods based on solid phase extraction to speed up the steps of sample extraction and purification and separation. This type of method mainly adheres functional particles to the outside of a solid rod, which only simplifies and improves the rapid pre-treatment of samples. The sample still needs to be migrated for extraction to achieve ionization and mass spectrometry analysis, and a complete analysis method independent of liquid chromatography-mass spectrometry technology has not been realized. In addition, the method of adhering the extraction material to the outside of the solid rod requires a sample volume far exceeding the actual volume that is effectively extracted during the extraction process, resulting in a waste of precious samples. It also has great limitations when facing trace sample analysis scenarios.

[0003] Extraction in a capillary can significantly save the sample volume, and porous polymers and other materials with large porosity have high specific surface areas, providing sufficient adsorption sites for the adsorption of analytes, which can improve the extraction rate and material recovery rate in the limited space of the capillary. Capillary and mass spectrometry analysis already have mature interface devices, which can directly perform electrospray ionization in situ for rapid analysis. Porous polymers can adjust the framework and pore size according to the structure and properties of the target analyte to enhance its adsorption selectivity, and can be functionally modified to enhance the interaction with the target analyte, eliminate the interference of complex sample matrices, and improve the selectivity of the analysis.

[0004] However, due to the extremely limited space inside the capillary wall and the inability to directly contact the inner wall surface, the process of fabricating solid-phase microextraction fibers cannot be directly transferred to the scenario of in-tube modification. Moreover, the free radical reaction used to modify the polymer has a fast reaction rate, making it difficult to accurately control the initiation and termination of the reaction. Polymerization in the capillary is prone to clogging the hollow structure. Therefore, the technology for modifying high-quality polymer thin layers on small-inner-diameter capillaries still needs further development.

[0005] Therefore, to meet the need for rapid analysis of specific substances in biological samples, a device and application technology for rapid detection of biological fluid samples highly coupled with mass spectrometry are required to meet the requirements of trace sample extraction and in-situ rapid ionization. Summary of the Invention

[0006] The present invention aims to solve at least one of the technical problems existing in the prior art. For this purpose, an object of the present invention is to provide a system for rotating in-situ preparation of a polymer-coated capillary and a method for rapid extraction, in-situ ionization, and photoderivatization reaction using a probe prepared thereby.

[0007] A first aspect of the present invention provides a system for rotating in-situ preparation of a polymer-coated capillary for preparing a polymer-coated capillary probe, wherein the in-situ polymer growth layer in the polymer-coated capillary probe is porous, has a uniform and stable thickness, and does not change the hollow structure of the capillary matrix.

[0008] According to an embodiment of the first aspect of the present invention, the system for rotating in-situ preparation of a polymer-coated capillary includes: A surface activation treatment module for treating the inner surface of the capillary matrix with a surface activation solution to form a pre-modified layer; A local ablation module configured to pattern the pre-modified layer, and the patterning method is electrothermal decomposition or laser mask irradiation; A rotary polymerization module including a motor, a rotary shaft, a clamping device, and a reaction excitation device. The clamping device clamps the capillary matrix and makes the capillary matrix coaxial with the rotary shaft, and drives the rotation through the motor and excites the in-situ polymerization of the monomer solution in the capillary matrix to generate an in-situ polymer growth layer; A control module electrically connected to the motor and the reaction excitation device, and controls the porosity and thickness of the in-situ polymer growth layer by adjusting the rotation speed and reaction time.

[0009] In summary, the rotation in-situ polymer-coated capillary system according to the first aspect embodiment of the present invention can prepare a polymer-coated capillary probe. The thickness of the in-situ growth layer of the polymer on the inner wall of the capillary matrix is uniform and stable, and the hollow structure of the capillary matrix is not changed, so that the polymer-coated capillary probe has an axial channel coaxial with the capillary matrix; the in-situ growth layer of the polymer is porous and has a large specific surface area.

[0010] In some embodiments, the surface activation treatment module fully rinses the inner surface of the capillary matrix with a surface activation solution, and the surface activation solution contains a bifunctional grafting reagent. The first functional group of the bifunctional grafting reagent is covalently bonded to the surface of the capillary matrix, and the second functional group of the bifunctional grafting reagent is covalently bonded to the polymer monomer, so that grafting active groups are obtained on the inner surface of the capillary matrix.

[0011] In some embodiments, the local ablation module includes an electric heating element with a required shape arranged on the outer wall of the capillary matrix or a photomask device arranged on the outer wall of the capillary matrix. The local grafting active groups on the inner surface of the capillary matrix are removed by pyrolysis; or a photomask is arranged on the outer wall of the capillary, and the active groups in the unmasked area are decomposed by laser irradiation.

[0012] In some embodiments, the various reactants in the monomer solution include a radical initiator, a polymer monomer, and an extraction modifier. The radical initiator, the polymer monomer, and the extraction modifier can undergo a polymerization reaction to generate a polymer. Among them, the radical initiator includes, but is not limited to, a radical initiator excited by ultraviolet light irradiation and a radical initiator excited by heating. The extraction modifier includes, but is not limited to, a hydrophilic group modifier, a hydrophobic group modifier, and a specific antibody. By changing the extraction modifier, the in-situ growth layer of the polymer can be modified to achieve highly selective extraction.

[0013] In some embodiments, the rotation polymerization module injects a monomer solution onto the inner surface of the capillary matrix, and the reactants are brought into contact and polymerized by rotation, and after washing and drying, the in-situ growth layer of the polymer is formed.

[0014] In some embodiments, the rotational polymerization module includes a motor, a rotating shaft, a clamping device, and a reaction excitation device. The rotary motor is connected to the rotating shaft. The clamping device is arranged on the rotating shaft. The clamping device clamps the capillary matrix and makes the axis of the capillary matrix coaxial with the rotating shaft. The reaction excitation device is arranged near one side of the capillary matrix. An appropriate amount of monomer solution is injected into the inner surface of the capillary matrix to make the monomer solution fully contact with the grafting active groups on the inner surface of the capillary matrix. Then, the capillary matrix is rotated around its own axis, and a variety of reactants in the monomer solution are excited by the reaction excitation device to undergo a polymerization reaction, so that the generated polymer grows and fixes directly in-situ on the pre-modified layer with a pattern on the inner surface of the capillary matrix, obtaining the patterned polymer in-situ growth layer.

[0015] In some embodiments, the control module and the reaction excitation module are electrically connected to control the operation of the motor and the reaction excitation module. The porosity of the polymer in-situ growth layer is controlled by adjusting the motor speed through the control module; the thickness of the polymer in-situ growth layer can be controlled by adjusting the excitation time of the polymerization reaction through the control module.

[0016] The second aspect of the present invention provides a polymer-coated capillary probe prepared by rotational in-situ.

[0017] According to the system for preparing a polymer-coated capillary by rotational in-situ in the first aspect embodiment of the present invention, the polymer-coated capillary probe in the second aspect embodiment of the present invention can be obtained. The thickness and position of the in-situ growth layer of the probe polymer are controllable, and the modification of the in-situ growth layer of the polymer is firm, without falling off during use.

[0018] The preparation method of the polymer-coated capillary probe in the second aspect embodiment of the present invention includes the following steps: S1: The inner surface of the capillary matrix is treated by the surface activation module to form a pre-modified layer; S2: The pre-modified layer on the inner surface of the capillary matrix is locally etched to make the remaining active groups on the inner surface of the capillary matrix form a patterned pre-modified layer; S3: A monomer solution is injected into the capillary matrix, the capillary matrix is clamped on the rotational polymerization module, the capillary is driven to rotate around its own axis, and a controllable in-situ polymerization reaction is excited to in-situ grow a patterned polymer in-situ growth layer at the patterned pre-modified layer on the inner surface of the capillary matrix.

[0019] The polymer coated capillary probe of the second aspect of the present invention has an axial channel coaxial with the capillary matrix and can absorb trace amounts of solution, and the solution flows unimpeded in the polymer coated capillary probe because the polymer in-situ growth layer grows coaxially in-situ on the inner surface of the capillary matrix and does not block the central channel of the capillary matrix.

[0020] By inhaling a trace amount of the solution to be tested, the polymer in-situ growth layer in the polymer coated capillary probe of the second aspect of the present invention can adsorb or enrich the target analyte in the solution to be tested; by inhaling a trace amount of the washing solution, the target analyte on the polymer in-situ growth layer in the polymer coated capillary probe of the second aspect of the present invention can be purified and impurities in the target analyte can be removed; by inhaling a trace amount of the eluent, the target analyte on the polymer in-situ growth layer in the polymer coated capillary probe of the second aspect of the present invention can be eluted or released into the eluent in the polymer coated capillary probe, and by applying high voltage to the polymer coated capillary probe, the eluent containing the target analyte in the polymer coated capillary probe of the second aspect of the present invention can be in-situ ionized and an electrospray can be formed at the closed tip.

[0021] When the elution solution contains a photoderivation reaction reagent, in situ ionization and photoderivation reactions can be carried out simultaneously in the polymer-coated capillary probe of the second aspect of the present invention, thereby realizing coupling with mass spectrometry and being compatible with a variety of chemical derivatization analysis methods, and being suitable for application scenarios such as high-throughput mass spectrometry analysis and in situ field detection.

[0022] When the polymer-coated capillary probe of the second embodiment of the present invention is used for extraction and detection, the operation process is simple, convenient and rapid, and the extraction effect is good and the detection sensitivity is high.

[0023] In some embodiments, the thickness of the polymer in-situ grown layer is uniform in different directions of any transverse cross-section perpendicular to the axis of the capillary matrix; the thickness of the polymer in-situ grown layer is uniform on any multiple transverse cross-sections with equal inner diameters perpendicular to the axis of the capillary matrix.

[0024] In some embodiments, the polymer in-situ grown layer is directly grown on the inner surface of the capillary matrix from a monomer solution through an in-situ reaction, and the polymer in-situ grown layer is a porous structure with adjustable porosity.

[0025] In some embodiments, the in-situ grown polymer layer is a continuously distributed in-situ grown polymer layer along the inner surface of the capillary matrix, or a patterned in-situ grown polymer layer discontinuously distributed along the inner surface of the capillary matrix, or a patterned in-situ grown polymer layer with multiple different modifications distributed at different parts of the inner surface of the capillary matrix.

[0026] In some embodiments, the material of the in-situ grown polymer layer includes but is not limited to organic polymers, silica microsphere crosslinked polymers, graphene, metal / covalent organic frameworks; the modification methods of the in-situ grown polymer layer include but are not limited to hydrophilic group modification, hydrophobic group modification, and addition of specific antibodies or aptamers.

[0027] An embodiment of the third aspect of the present invention provides an application of a polymer-coated capillary probe, which is used for in-situ extraction and detection of target substances in whole blood, plasma or urine samples, and the in-situ extraction and detection can be combined with chemical derivatization methods.

[0028] The additional aspects and advantages of the present invention will be partially given in the following description, partially become apparent from the following description, or be understood through the practice of the present invention. Description of the Drawings

[0029] Figure 1 It is a schematic structural diagram of a system for rotating in-situ preparation of a polymer-coated capillary of the present invention; Figure 2 It is a schematic working process diagram of the local ablation module of the system of the present invention; Figure 3 It is a schematic structural diagram of the rotating polymerization module of the system of the present invention; Figure 4 It is a schematic working process diagram of the rotating polymerization module of the system of the present invention; Figure 5 It is a cross-sectional scanning electron microscope photograph of the polymer-coated capillary prepared by the system of the present invention; Figure 6a It is a curve showing the relationship between the thickness of the in-situ grown polymer layer of the polymer-coated capillary prepared by the system of the present invention and the polymerization reaction time; Figure 6b It is a scanning electron microscope photograph of the thickness of the in-situ grown polymer layer of the polymer-coated capillary prepared by the system of the present invention with different polymerization reaction time lengths; Figure 7 It is a schematic structural diagram of the polymer-coated capillary probe prepared by the system of the present invention; Figure 8 It is a physical photograph and a microscopic imaging schematic diagram of the polymer-coated capillary probe and the capillary matrix of the present invention; Figure 9 Schematic diagram for comparing the extraction effect of the polymer-coated capillary probe of the present invention with the number of lipid species extracted by the liquid-liquid extraction method; Figure 10a Mass spectrometry diagram in positive ion mode of the polymer-coated capillary probe of the present invention for extracting plasma samples; Figure 10b Mass spectrometry diagram in negative ion mode of the polymer-coated capillary probe of the present invention for extracting plasma samples; Figure 11a Effect diagram of the polymer-coated capillary probe of the present invention for extracting phosphatidylcholine; Figure 11b Effect diagram of the polymer-coated capillary probe of the present invention for extracting phosphatidylethanolamine; Figure 11c Effect diagram of the polymer-coated capillary probe of the present invention for extracting triglyceride; Figure 12 Schematic diagram of the identification result of the unsaturated lipid structure in human plasma samples analyzed by the polymer-coated capillary probe of the present invention.

[0030] Reference numerals: System 1000 for rotating in-situ preparation of polymer-coated capillary; surface activation treatment module 1; local ablation module 2; electric heating element 201; photomask device 202; rotating polymerization module 3; motor 301, rotating shaft 302, clamping device 303; reaction excitation device 304; control module 4; polymer-coated capillary probe 2000; main pipe section 501; closed end pipe section 502; tip pipe section 503; capillary matrix 5; main pipe section 501, closed end pipe section 502; tip pipe section 503; pre-modified layer 6; patterned pre-modified layer 6'; polymer in-situ growth layer 7. Detailed implementation manners The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals indicate the same or similar elements or elements with the same or similar functions from beginning to end. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation to the present invention.

[0031] The following will be combined with Figures 1 to 12 to describe the system 1000 for rotating in-situ preparation of polymer-coated capillary of the embodiments of the present invention, the method for preparing the polymer-coated capillary probe 2000 using this system, and the method for extraction and photo-derivatization reaction in the polymer-coated capillary probe 2000.

[0032] As Figure 1 shown, a first aspect of the present invention provides a system 1000 for rotating in-situ preparation of polymer-coated capillary.

[0033] A system 1000 for rotation in-situ preparation of a polymer-coated capillary according to an embodiment of the first aspect of the present invention includes the following components: a surface activation treatment module 1, a local ablation module 2, a rotation polymerization module 3, and a control module 4. Among them, the surface activation treatment module 1 is used to treat the inner surface of the capillary matrix with a surface activation solution to form a pre-modified layer; the local ablation module 2 is configured to pattern the pre-modified layer, and the patterning method is electrothermal decomposition or laser mask irradiation; the rotation polymerization module 3 includes a motor 301, a rotating shaft 302, a clamping device 303, and a reaction excitation device 304. The clamping device clamps the capillary matrix 5 and makes the capillary matrix 5 coaxial with the rotating shaft 302, and drives rotation through the motor 301 and excites in-situ polymerization of the monomer solution to generate a polymer in-situ growth layer 7; the control module 4 is electrically connected to the motor 301 and the reaction excitation device 304, and controls the porosity and thickness of the coating (i.e., the polymer in-situ growth layer 7) by adjusting the rotation speed (2000 - 12000 rpm) and the reaction time (30 - 500 s).

[0034] In some embodiments, the surface activation solution used in the surface activation treatment module 1 contains a bifunctional grafting reagent. The first functional group of the bifunctional grafting reagent covalently binds to the surface of the capillary matrix 5, and the second functional group of the bifunctional grafting reagent covalently binds to the polymer monomer. This is conducive to firmly connecting the pre-modified layer 6 to the capillary matrix 5 and the polymer in-situ growth layer 7.

[0035] In some embodiments, the local ablation module 2 includes an electrothermal element 201 with a required shape provided on the outer wall of the capillary matrix 5 or a photomask device 202 provided on the outer wall of the capillary matrix 5. Specifically, as Figure 2 shown, the local ablation module 2 is specifically that the electrothermal element 201 heats a local position of the capillary matrix 5, and the local grafting active groups on the inner surface of the capillary matrix 5 are removed through pyrolysis to obtain a patterned pre-modified layer 6'; or a photomask device 202 is provided on the outer wall of the capillary matrix 5, and the active groups in the unmasked area are decomposed by laser irradiation to obtain a patterned pre-modified layer 6'. Furthermore, a corresponding patterned polymer in-situ growth layer 7 can be modified inside the capillary matrix 5.

[0036] In some embodiments, the monomer solution contains a radical initiator, a polymerization monomer, and an extraction modifier. Among them, the radical initiator includes, but is not limited to, a radical initiator excited by ultraviolet light irradiation and a radical initiator excited by heating. The extraction modifier includes, but is not limited to, a hydrophilic group modifier, a hydrophobic group modifier, and a specific antibody. By changing the extraction modifier, the polymer in-situ growth layer 7 can be modified to achieve highly selective extraction.

[0037] In some embodiments, the rotary polymerization module 3 injects a monomer solution onto the inner surface of the capillary matrix 5, and through rotation, the reactants are brought into contact and polymerized. After washing and drying, a polymer in-situ growth layer 7 is formed. Specifically, as Figure 3 shown, the rotary polymerization module 3 includes a motor 301, a rotary shaft 302, a clamping device 303, and a reaction excitation device 304; the control module 4 is connected to the motor 301 and the reaction excitation device 304; the motor 301 is connected to the rotary shaft 302 and is used to drive the rotary shaft 302 to rotate around its own axis. The clamping device 303 is arranged on the rotary shaft 302. The clamping device 303 clamps the capillary matrix 5 and makes the capillary matrix 5 coaxial with the rotary shaft 302. In this way, the capillary matrix 5 rotates synchronously with the rotary shaft 302 around its own axis. The reaction excitation device 304 is arranged near one side of the capillary matrix 5 to excite various reactants in the monomer solution in the capillary matrix 5 to undergo a polymerization reaction. The generated polymer particles settle onto the inner surface of the capillary matrix 5 under the action of centrifugal force and further polymerize and solidify on the inner surface of the capillary matrix 5, ensuring the coating adhesion strength while maintaining the porous morphology, ensuring that the polymer-coated capillary probe 2000 has a central axis channel and can normally aspirate and release the solution. Therefore, a polymer-coated capillary probe 2000 with a smaller spray opening can be prepared for the detection of more trace samples.

[0038] The control module 4 is electrically connected to the motor 301 and the reaction excitation device 304 to control the operation of the motor 301 and the reaction excitation device 304. By adjusting the rotation speed of the rotary motor 301, the magnitude of the centrifugal force can be controlled, and further, characteristics such as the porosity of the polymer in-situ growth layer 7 can be controlled; by adjusting the length of the polymerization reaction time, the thickness of the polymer in-situ growth layer 7 can be controlled. Using this device to prepare a thin-layer polymer material microextraction probe (polymer-coated capillary probe 2000), a probe with a highly uniform inner wall polymer thickness and a controllable modification thickness can be obtained, and the hollow nature of the polymer-coated capillary probe 2000 will not be changed, ensuring that the polymer-coated capillary probe 2000 has an axis channel.

[0039] In some embodiments, the reaction excitation device 304 includes, but is not limited to, an ultraviolet light source module and a heating source module, which can be selected according to actual needs. As Figure 3 and Figure 4As shown below, a specific example of the preparation method of a polymer-coated capillary probe is given. After the inner surface of the capillary substrate 5 is thoroughly cleaned and the surface groups are activated, a grafting reagent is used to pre-modify the patterned grafting active groups, and the grafting active groups form a pre-modified layer 6. The inside of the capillary substrate 5 is filled with a monomer solution containing components such as polymerization monomers and radical initiators, and the monomer solution is brought into full contact with the surface to be modified. The capillary substrate 5 is fastened on the clamping device 303, and the axis of the capillary substrate 5 is collinear with the rotating shaft 302. Rotation is started and the polymerization reaction is excited. Under the condition of rotation around the axis, the polymer generated by the polymerization reaction is deposited on the inner surface of the capillary substrate 5 under the action of centrifugal force and connected to each other to form a uniform in-situ polymer growth layer 7. Due to the symmetry of rotation, the thickness of the polymer grown on each part of the capillary substrate 5 is uniform and stable, and the polymer is only distributed on the inner surface, without changing the hollow structure of the capillary substrate 5, so that the polymer-coated capillary probe 2000 has an axial channel coaxial with the capillary substrate 5.

[0040] Figure 5 (a) in it is the scanning electron microscope image of the in-situ polymer growth layer 7, and it can be seen that the in-situ polymer growth layer 7 grown on the capillary substrate 5 has the characteristics of being porous and having a large specific surface area; Figure 5 (b) and (c) in it are the cross-sectional scanning electron microscope images of the capillary substrate 5, and it can be seen that a uniform in-situ polymer growth layer 7 is attached to the inner wall of the capillary substrate 5, and at the tip part of one end of the polymer-coated capillary probe 1000, there is still a layer uniformly grown on the inner surface of the capillary substrate 5, indicating that the tip of the capillary substrate 5 also has the function of extraction. By adjusting the length of the polymerization reaction time, the thickness of the in-situ polymer growth layer 7 can be controlled, as Figure 6a and Figure 6b shown.

[0041] As shown in Figure 6, the porosity of the in-situ polymer growth layer 7 is controlled by adjusting the motor speed through the control module 4; by adjusting the excitation time of the polymerization reaction through the control module 4, the thickness of the in-situ polymer growth layer 7 can be controlled, and the excitation time of the polymerization reaction is 30 - 500 s. Thus, the polymer-coated capillary probe 2000 can be rapidly prepared, and the thickness of the polymer-coated capillary probe 2000 is highly correlated with the polymer reaction time.

[0042] In summary, the rotation in-situ preparation polymer-coated capillary system 1000 according to the first aspect embodiment of the present invention can prepare a polymer-coated capillary probe 2000. The thickness of the in-situ polymer growth layer 7 on the inner wall of the capillary substrate 5 is uniform and stable, and does not change the hollow structure of the capillary substrate 5, so that the polymer-coated capillary probe 2000 has an axial channel coaxial with the capillary substrate 5; the in-situ polymer growth layer 7 has the characteristics of being porous and having a large specific surface area.

[0043] In the second aspect of the embodiments of the present invention, a polymer-coated capillary probe 2000 prepared by in-situ rotation is proposed.

[0044] As Figure 7 shown, the polymer-coated capillary probe 2000 of the second aspect of the embodiments of the present invention is prepared by using the system 1000 for in-situ rotation preparation of polymer-coated capillaries in the first aspect of the embodiments of the present invention.

[0045] Figure 8 The photos and optical microscope images of the polymer-coated capillary probe 2000 are taken for the in-situ controllable and uniform growth of the thin polymer in-situ growth layer 7 in the prepared capillary substrate 5. Compared with the capillary substrate 5 before modification, the inner surface of the modified polymer-coated capillary probe 2000 is covered with an opaque polymer in-situ growth layer 7. The appearance structure of the substrate capillary substrate 5 is not damaged before and after modification, and the hollow characteristic of the capillary substrate 5 is also retained.

[0046] In some embodiments, the capillary substrate 5 in the capillary probe 2000 includes a main tube section 501, a necked tube section 502, and a tip tube section 503 that are coaxially and sequentially connected. The tip tube section 503 can be used as a sampling tube section, that is, by inserting the tip tube section 503 into the solution, so that the polymer-coated capillary probe 2000 can suck in the solution; the necked tube section 502 can be used as an electrospray ionization tube section, that is, by applying a high voltage to the polymer-coated capillary probe 2000, an electrospray is generated at the necked tip of the necked tube section 502 of the capillary substrate 5 for the solution inside. The material of the capillary substrate 5 includes but is not limited to glass, quartz, polypropylene, polyether ether ketone, other polymer materials, etc.

[0047] The in-situ grown polymer layer 7 is tubular and coaxially in-situ grown on the inner surface of the tip tube section 503, the necking tube section 502, or / and the main tube section 501, enabling the polymer-coated capillary probe 2000 to have an axial channel. That is to say, the in-situ grown polymer layer 7 is obtained by directly depositing and fixing the polymer formed by the polymerization reaction of various reactants in the monomer solution in the capillary matrix 5 on the inner surface of the capillary matrix 5 in-situ. The in-situ grown polymer layer 7 is tubular and coaxially attached to the inner surface of the capillary matrix 5 without blocking the central channel of the capillary matrix 5, enabling the polymer-coated capillary probe 2000 to have an axial channel coaxial with the capillary matrix 5, ensuring that the polymer-coated capillary probe 2000 can suck in the solution, and the solution can flow freely without obstruction in the axial channel of the polymer-coated capillary probe 2000; the position of the in-situ grown polymer layer 7 in the capillary matrix 5 can be controlled and can be fixed on the inner surface of the tip tube section 503, the inner surface of the necking tube section 502, or / and the inner surface of the main tube section 501 according to actual needs. The in-situ grown polymer layer 7 has a high specific surface area and can quickly adsorb or enrich the target analyte in the solution to be measured.

[0048] In some embodiments, the preparation method of the polymer-coated capillary probe 2000 includes the following steps, as Figure 4 shown: S1: Treat the inner surface of the capillary matrix 5 with a surface activation solution to form a pre-modified layer 6.

[0049] S2: Perform local etching treatment on the pre-modified layer 6 on the inner surface of the capillary matrix 5 to form a patterned pre-modified layer 6' from the remaining active groups on the inner surface of the capillary matrix 5.

[0050] S3: Inject a monomer solution into the capillary substrate 5, clamp the capillary substrate 5 on the rotary polymerization module 3, and drive the capillary substrate 5 to rotate around its own axis. Through a controllable in-situ polymerization reaction, a patterned polymer in-situ growth layer 7 is in-situ grown at the patterned pre-modification layer 6' on the inner surface of the capillary substrate 5. That is, the polymer in-situ growth layer 7 is directly in-situ deposited and fixed on the inner surface of the capillary substrate 5 by the polymer formed by the polymerization reaction of various reactants in the monomer solution. The polymer in-situ growth layer 7 is coaxially and tubularly fixed on the inner surface of the capillary substrate 5 without blocking the central channel of the capillary substrate 5, so that the polymer-coated capillary probe 2000 has an axial channel coaxial with the capillary substrate 5, ensuring that the polymer-coated capillary probe 2000 can suck in the solution and the solution can flow freely without obstruction in the axial channel of the polymer-coated capillary probe 2000; the position of the polymer in-situ growth layer 7 in-situ grown in the capillary substrate 5 is controllable and can be fixed on the inner surface of the necked tube section 502, can be fixed on the inner surface of the main tube section 501, or can be fixed on the inner surfaces of both the necked tube section 502 and the main tube section 501 according to actual needs. The polymer in-situ growth layer 7 has a high specific surface area and can quickly adsorb or enrich target analytes in the solution to be measured.

[0051] Through step S3, a polymer in-situ growth layer 7 with extremely uniform thickness along the inner surface of the capillary substrate 5 can be prepared, and the polymer in-situ growth layer 7 can be modified even when the spray end opening is extremely small without causing blockage at the spray end opening. The polymer particles generated in the monomer solution settle to the inner surface of the capillary substrate 5 under the action of centrifugal force and are further polymerized and consolidated on the inner surface of the capillary substrate 5, ensuring the adhesion strength of the polymer in-situ growth layer 7 while maintaining the porous morphology, and ensuring that the polymer-coated capillary probe 2000 can normally suck in and release the solution. Therefore, a probe with a smaller spray opening can be prepared for the detection of more trace samples. Also, because most of the generated polymer particles finally settle to the inner surface of the capillary substrate 5 and are consolidated, the thickness of the polymer in-situ growth layer 7 is highly correlated with the polymerization reaction time. By controlling the duration of the polymerization reaction, the thickness of the polymer in-situ growth layer 7 inside the capillary substrate 5 can be controlled. The quality of the polymer-coated capillary probes 2000 prepared in different batches is stable, which is convenient for large-scale preparation of polymer-coated capillary probes 2000 for high-throughput analysis.

[0052] In some embodiments, the thickness of any transverse cross-section of the in-situ grown polymer layer 7 perpendicular to the axis of the capillary matrix 5 is uniform in different directions; on any plurality of transverse cross-sections with equal inner diameters perpendicular to the axis of the capillary matrix 5, the thickness of the in-situ grown polymer layer 7 is uniform. This is beneficial for not changing the characteristics of the central channel of the capillary matrix 5, enabling the polymer-coated capillary probe 2000 to have an axial channel coaxial with the capillary matrix 5.

[0053] In some embodiments, the material of the in-situ grown polymer layer 7 includes but is not limited to organic polymers, silica microsphere crosslinked polymers, graphene, metal / covalent organic frameworks; the modification methods of the in-situ grown polymer layer 7 include hydrophilic / hydrophobic group modification or antibody / aptamer addition, which can achieve highly selective extraction.

[0054] In some embodiments, as shown in FIG. 6, the in-situ grown polymer layer 7 is a porous structure with adjustable porosity, which is directly formed by an in-situ polymerization reaction. That is to say, the porosity of the in-situ grown polymer layer 7 can be regulated during the in-situ growth of the in-situ grown polymer layer 7, so as to achieve the enrichment of the target analyte by the in-situ grown polymer layer 7.

[0055] In some embodiments, the in-situ grown polymer layer 7 can be continuously distributed, discontinuously patterned distributed, or multi-modified section distributed, and can be directly formed by an in-situ polymerization reaction according to actual needs. In some embodiments, obviously, the in-situ grown polymer layer 7 can be provided on the inner surface of the capillary matrix 5 with a very small inner diameter without changing the hollow characteristics of the capillary matrix 5. The polymer-coated capillary probe 2000 has an axial channel for liquid flow inside, which is beneficial for saving the sample to be tested and achieving rapid enrichment, and has high detection sensitivity.

[0056] The third aspect embodiment of the present invention proposes an application of a polymer-coated capillary probe. The polymer-coated capillary probe 2000 is used for in-situ extraction and detection of target substances in whole blood, plasma or urine samples, and this in-situ extraction and detection can be combined with a chemical derivatization method.

[0057] For example, the extraction method in the polymer-coated capillary probe of the embodiment of the present invention is used to detect plasma samples. Figure 9 、 Figures 10a - 10b 、 Figures 11a - 11cThey are respectively the statistical comparison chart of various lipid species identified in the extracts of the polymer-coated capillary probe 2000 proposed in the third aspect of the present invention and the extracts of traditional liquid-liquid extraction, the comparison of mass spectrometry diagrams collected in positive and negative ion modes, and the mass spectrometry comparison diagram of phosphatidylcholine, phosphatidylethanolamine, and triglyceride species detected. It can be seen that the results obtained by the rapid extraction method proposed in the third aspect of the present invention are basically the same as those obtained by the current industry gold standard, and most of the lipids can be extracted, and the time used is greatly shortened.

[0058] The extraction of the polymer-coated capillary probe in the embodiment of the present invention is compatible with the photochemical derivatization reaction method. When preparing an elution solution containing a photochemical derivatization reaction reagent, the same method is used for elution. During in-situ ionization spraying, a light source with a characteristic wavelength is placed on the side of the polymer-coated capillary probe 2000 where electrospray is generated, and the photochemical derivatization reaction can be carried out online during the electrospray process, enabling a more accurate judgment of the molecular structure of the substance to be analyzed. Figure 12 It shows the results of identifying the positions of carbon-carbon double bonds of unsaturated phosphatidylcholine and phosphatidylethanolamine in human plasma by adding acetone as a photochemical derivatization reagent to the elution solvent. The photochemical derivatization reaction is carried out on the lipid, and the position information of the carbon-carbon double bond of the lipid is obtained through tandem mass spectrometry analysis, thereby enabling the fine structure analysis of the lipid. It can be seen that phosphatidylcholine PC 34:1 has two double bond position isomers, Δ9 and Δ11, reflecting that this method can simultaneously carry out in-situ photochemical derivatization reaction for fine structure analysis.

[0059] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0060] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and purposes of the present invention, and the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A system for in-situ preparing a polymer-coated capillary by rotation, characterized in that, Comprising: A surface activation treatment module for treating the inner surface of a capillary matrix with a surface activation solution to form a pre-modified layer; A local ablation module configured to perform patterning treatment on the pre-modified layer, and the patterning treatment method is electric heating decomposition or laser mask irradiation; A rotary polymerization module including a motor, a rotary shaft, a clamping device and a reaction excitation device, the clamping device clamps the capillary matrix and makes the capillary matrix coaxial with the rotary shaft, and drives rotation through the motor and excites in-situ polymerization of the monomer solution in the capillary matrix to generate a polymer in-situ growth layer; A control module is electrically connected to the motor and the reaction excitation device, and controls the porosity and thickness of the polymer in-situ growth layer by adjusting the rotation speed and reaction time.

2. The system for in-situ preparation of a polymer-coated capillary by rotation according to claim 1, characterized in that, The surface activation solution used by the surface activation treatment module contains a bifunctional grafting reagent, the first functional group of the bifunctional grafting reagent is covalently bonded to the surface of the capillary matrix, and the second functional group of the bifunctional grafting reagent is covalently bonded to the polymer monomer.

3. The system for rotation in-situ preparation of a polymer-coated capillary according to claim 1, wherein The local ablation module includes an electric heating element with a required shape arranged on the outer wall of the capillary matrix or a photomask device arranged on the outer wall of the capillary matrix.

4. The system for in-situ preparation of a polymer-coated capillary by rotation according to claim 1, characterized in that, The monomer solution contains a radical initiator, a polymerization monomer and an extraction modifier.

5. The system for in-situ preparing a polymer-coated capillary by rotation according to claim 1, wherein The rotary polymerization module injects the monomer solution onto the inner surface of the capillary matrix, makes the reactants contact and polymerize by rotation, and forms the polymer in-situ growth layer after washing and drying.

6. A polymer-coated capillary probe, characterized in that, The polymer-coated capillary probe is prepared by the system for rotating in-situ preparing a polymer-coated capillary according to any one of claims 1-5. The thickness of the polymer in-situ growth layer is uniform on any transverse section of the inner surface of the capillary matrix, and the inner diameters of different axial sections are equal.

7. The polymer-coated capillary probe according to claim 6, characterized in that, Its preparation method includes the following steps: S1: Treat the inner surface of the capillary matrix through the surface activation module to form a pre-modified layer; S2: Perform local ablation treatment on the pre-modified layer on the inner surface of the capillary matrix, so that the remaining active groups on the inner surface of the capillary matrix form a patterned pre-modified layer; S3: Inject the monomer solution into the capillary matrix, clamp the capillary matrix on the rotary polymerization module, drive the capillary matrix to rotate around its own axis, and excite a controllable in-situ polymerization reaction to in-situ grow a patterned polymer in-situ growth layer at the patterned pre-modified layer on the inner surface of the capillary matrix.

8. The polymer-coated capillary probe according to claim 6, characterized in that, The polymer in-situ growth layer is a porous structure with adjustable porosity and is directly generated by an in-situ polymerization reaction.

9. The polymer-coated capillary probe according to claim 6, characterized in that, The polymer in-situ growth layer is continuously distributed, discontinuously patterned distributed or multi-modified section distributed.

10. The polymer-coated capillary probe according to claim 6, wherein, The material of the polymer in-situ growth layer includes organic polymers, silica microsphere cross-linked polymers, graphene, metal / covalent organic frameworks; the modification method of the polymer in-situ growth layer includes hydrophilic / hydrophobic group modification or antibody / aptamer addition.

11. Application of a polymer-coated capillary probe, characterized in that, The polymer-coated capillary probe is the polymer-coated capillary probe described in any one of claims 6-10, and is used for in-situ extraction and detection of target substances in whole blood, plasma or urine samples, and the detection can be combined with a chemical derivatization method.

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