A split-flow in-situ matrix purification liquid-liquid electroextraction device, method and application

Abstract

The present application relates to a kind of shunt-in-situ matrix purification liquid-liquid electroextraction device, method and application, it is related to chemical analysis technical field.The device includes: extraction component, including push-pull device, injector electrode and shunt pipe, injector electrode includes the injector electrode wire and injector connected, injector is used to accommodate electric conductive liquid, push-pull device drives the piston of injector to carry out push-pull movement, one end of injector electrode wire is connected with injector, the other end is grounded or connected power supply;One end of shunt pipe is communicated with injector, the other end is used to immerse in the extraction object;And sample component, including sample container, sample electrode wire, one end of sample electrode wire is used to immerse in the extraction object, the other end is used for grounding or connecting power supply;Sample container is used to accommodate extraction object.The equipment can reduce the risk of generating bubble by shunt, improve baseline stability and electroextraction efficiency.

Description

Technical Field

[0001] This invention relates to the field of chemical analysis technology, and in particular to a diversion-in-situ matrix purification solution-electrohydride extraction device, method and application. Background Technology

[0002] Liquid-liquid electro-extraction (LC-EIE) technology has demonstrated numerous compelling advantages, but its practical application faces challenges due to complex matrix interference. On one hand, while theoretically the extraction rate of LC-EIE can be significantly increased by indefinitely increasing the electric field (e.g., by raising the voltage), the sample matrix actually increases the conductivity of the electro-extraction system, leading to increased current and Joule heating. This localized temperature rise can cause bubble formation, interfering with or even interrupting the extraction process. Simultaneously, increasingly vigorous electrode reactions can also contribute to bubble generation. Bubble problems severely limit the improvement of electro-extraction efficiency. On the other hand, complex matrix components can interfere with the electro-extraction process, resulting in decreased extraction rate and reduced stability. Co-extracted impurities can also cause matrix effects. These problems directly lead to excessively long electro-extraction times, low extraction recoveries, and poor extraction precision and accuracy, making it difficult to achieve exhaustive extraction.

[0003] Therefore, establishing a liquid-liquid electro-extraction technology and device that is simple to operate, low in cost, has excellent enrichment effect, strong matrix purification ability, and can avoid the generation of bubbles in the miscible two phases is of great practical significance for the further development and promotion of the practical application of electro-extraction technology. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a diversion-in-situ matrix purification liquid-electrohydride extraction device. This device can reduce the risk of bubble generation by diverting the liquid, thereby improving the efficiency and stability of electro-extraction.

[0005] To achieve the above objectives, the present invention provides a diversion-in-situ matrix purification solution-electrohydride extraction device, comprising: An extraction assembly includes a push-pull device, a syringe electrode, and a shunt tube. The syringe electrode includes a connected syringe electrode wire and a syringe, which contains an electrolytic fluid. The push-pull device drives a piston in the syringe to perform a push-pull motion. One end of the syringe electrode wire is connected to the syringe, and the other end is grounded or connected to a power source. One end of the shunt tube is connected to the syringe, and the other end is used to immerse the extractant. The sample assembly includes a sample container and a sample electrode wire, one end of which is used to immerse the sample to be extracted, and the other end is used to ground or connect to a power source; the sample container is used to hold the sample to be extracted.

[0006] During the research process, the inventors discovered that the risk of bubble formation can be reduced by increasing the number of pipes in the shunt tube. Specifically, increasing the number of pipes in the shunt tube reduces the actual current flowing through each pipe under the same conditions, thereby reducing the temperature rise of each pipe and ultimately reducing the risk of bubble formation.

[0007] Meanwhile, the aforementioned device, by connecting the syringe electrode wire to the syringe to form a "syringe electrode" structure, allows for convenient control of solution collection and device cleaning via a syringe pump. Sufficient conductive liquid in the syringe can be used for multiple sample electroextractions, improving the efficiency of electroextraction. Furthermore, the significant difference in cross-sectional areas between the conventional sample container and the splitter tube facilitates faster diffusion mass transfer within the sample container while significantly suppressing diffusion mass transfer within the splitter tube, thus preventing the back-diffusion of target substances (including the test sample or standard sample) back into the sample container. When using the aforementioned device for split-in-situ matrix purification-electrohydride extraction, the target substances in the sample container gradually form a target substance enrichment zone in the splitter tube after electroextraction. This zone is far from the contact surface between the sample container and the splitter tube, preventing the back-diffusion of target substances from the splitter tube back into the sample container.

[0008] In one embodiment, the other end of the syringe electrode wire is grounded or connected to the high-voltage output terminal of the power supply; the other end of the sample electrode wire is grounded or connected to the high-voltage output terminal of the power supply.

[0009] In one embodiment, the number of pipes in the shunt pipe is ≥1.

[0010] In one embodiment, the number of pipes in the shunt pipe is 1 to 11.

[0011] In one embodiment, the number of pipes in the diversion pipe is 3 to 10.

[0012] In one embodiment, the number of pipes in the shunt pipe is 5.

[0013] In one embodiment, one end of the syringe electrode wire is inserted into the tail of the syringe piston rod and exposed at the head of the piston rod.

[0014] The aforementioned syringe electrode wire, once exposed from the head of the piston rod, can be submerged in the conductive fluid.

[0015] In one embodiment, the substance to be extracted includes a sample or a standard.

[0016] In one embodiment, the shunt tube is connected to the syringe via a Luer connector or a hollow plastic cone.

[0017] In one embodiment, the shunt is an insulated shunt with a length of 35-45 cm and an inner diameter of 0.3-1.0 mm.

[0018] In one embodiment, the sample container is an insulated sample container with a capacity of 5-15 mL, a height of 6-8 cm, and an inner diameter of 1-2 cm.

[0019] In one embodiment, the power source is a positive high voltage power source of 0~30kV or a negative high voltage power source of -30~0kV.

[0020] In one embodiment, the syringe electrode wire is a stainless steel electrode wire, and the sample electrode wire is a platinum double-ring electrode wire. The diameters of both the syringe electrode wire and the sample electrode wire are 0.3~0.7 mm.

[0021] In one embodiment, the push-pull device is an injection pump with a flow rate of 150~250μL / min and the syringe has a capacity of 5~10mL.

[0022] The present invention also provides a split-in-situ matrix purification solution-electrohydride extraction method, comprising the following steps: preparing a sample to be extracted, preparing a standard, and using the aforementioned split-in-situ matrix purification solution-electrohydride extraction device to perform electro-extraction on the sample to be extracted and the standard to obtain a test sample and a standard sample; the test sample is enriched in a split tube; The step of preparing the sample to be extracted includes: mixing the sample with a purifying agent and extracting it with a solvent to obtain the sample to be extracted; The steps for preparing the standard include: mixing the standard solution with a purifying agent, extracting it with a solvent, and obtaining the standard.

[0023] The aforementioned miscible two-phase liquid-liquid electro-extraction method achieves matrix purification and selective extraction by adding a purifying agent, thereby realizing efficient concentration and enrichment. It is simple to operate, low in cost, and produces excellent enrichment results. During extraction, the target analyte undergoes a continuous deceleration migration effect in the split tube and tends to stagnate, achieving regional enrichment and ultimately producing an enrichment zone.

[0024] In one embodiment, the sample to be tested can be pushed out of the shunt tube by a push-pull device using a syringe, and analyzed and detected using an online coupled analysis device or collected in a container for analysis and detection.

[0025] In one embodiment, the conditions for electro-extraction include: immersing the shunt tube and sample electrode wire into the substance to be extracted, using an extraction voltage of -100kV to 100kV, wherein the extraction voltage is not 0, and an extraction time of ≤200min.

[0026] In one embodiment, the extraction voltage is 0~60kV or 0~-60kV, and the extraction voltage is not 0.

[0027] In one embodiment, the purifying agent comprises at least one of silica gel, bonded silica gel, porous carbon materials, metal oxides, metal salts, metal-organic frameworks, covalent organic frameworks, microporous organic polymers, functional polymers, ionic liquids, eutectic solvents, supramolecular solvents, surfactants, adsorption resins, anion exchange resins, cation exchange resins, molecularly imprinted polymers, magnetic nanomaterials, activated carbon, activated carbon fibers, graphitized carbon black, graphene, graphene oxide, carbon nanotubes, carbon nanoparticles, melamine sponges, hydrogels, metal hydroxides, metal complexes, complexing agents, chitosan, chitin, N-propylethylenediamine bonded silica gel adsorbents, magnesium sulfate, cyclodextrin, urea, zirconium oxide, titanium dioxide, polyethylene glycol, polystyrene, or octadecyl silica, wherein the mass ratio of the sample or standard solution to the purifying agent is 10000:1 to 1:10. The solvents include methanol, acetonitrile, ethanol, water, ethyl acetate, butyl acetate, isoamyl acetate, isopropyl acetate, benzoyl acetate, isoborneol acetate, bornyl acetate, linalyl acetate, geraniol acetate, cinnamyl acetate, ethyl benzoate, methyl benzoate, butyl benzoate, isoamyl benzoate, isopropyl benzoate, isopropanol, n-butanol, tert-butanol, isoamyl alcohol, benzyl alcohol, geraniol, linalool, higher fatty alcohols, diethyl ether, methyl ether, methyl tert-butyl ether, tetrahydrofuran, diethyl ether, benzaldehyde, cinnamaldehyde, vanillin, citral, dichloromethane, chloroform, carbon tetrachloride, n-hexane, n-heptane, n-octane, isooctane, cyclohexane, methylcyclohexane, petroleum ether, formic acid, acetic acid, and lipids. Fatty acid, ammonia, dimethyl sulfoxide, butanone, trifluoroacetic acid, ethyl trifluoroacetate, methyl trifluoroacetate, isopropyl trifluoroacetate, isobutyl trifluoroacetate, isoamyl trifluoroacetate, isohexyl trifluoroacetate, isohexyl trifluoroacetate, isooctyl trifluoroacetate, isodecyl trifluoroacetate, ethylene trifluoroacetate, propylene trifluoroacetate, butyl trifluoroacetate, pentane trifluoroacetate, hexane trifluoroacetate, octane trifluoroacetate, decane trifluoroacetate, pentaerythritol trifluoroacetate, sorbitol trifluoroacetate, mannitol trifluoroacetate, dimethylformamide, pyridine, benzene, toluene, carbon disulfide, dimethyl carbonate, diethyl carbonate, 1,4-dioxane, and acetone, at least one of these. The conductive solution for electroextraction includes a conductive solvent and an electrolyte. The concentration of the electrolyte in the conductive solution is 0~1 mol / L, and the electrolyte includes an acid, a base, or a salt.

[0028] The above-mentioned conductive solution can also achieve electro-extraction when the electrolyte concentration is 0, but the electro-extraction effect is better after adding electrolyte.

[0029] In one embodiment, the magnesium sulfate is anhydrous magnesium sulfate.

[0030] In one embodiment, the conductive solvent includes methanol.

[0031] In one embodiment, the acid includes an organic acid, which includes at least one of malonic acid, phthalic acid, acetic acid, and formic acid; the base includes an organic base, which includes at least one of triethylamine, diethylamine, and ammonium acetate.

[0032] The present invention also provides an electro-extraction analysis method, comprising the following steps: extracting the analyte using the split-in-situ matrix purification solution-liquid electro-extraction method to obtain the analyte sample or standard sample, analyzing and detecting it using an online coupled analysis device or collecting it into a container for analysis and detection, and comparing the obtained spectra.

[0033] In one embodiment, the comparison includes: comparing and analyzing the liquid chromatography spectrum of the sample to be tested with the liquid chromatography spectrum or mass spectrometry spectrum of the standard sample, and calculating the content of the target component in the analyte.

[0034] The present invention also provides the application of the electroextraction analysis method in the detection of shellfish toxins and / or sulfonamides.

[0035] The present invention also provides a method for detecting shellfish toxins, comprising the following steps: detecting the analyte using the electroextraction analysis method described above; The purifying agent includes chitosan, and the mass ratio of the analyte to the purifying agent is 10000:1 to 1:10; the solvent includes acetonitrile.

[0036] In one embodiment, in the method for detecting shellfish toxins, the extraction voltage is -4.5 to -3.5 kV, and the extraction time is 10 to 16 min.

[0037] In one embodiment, the method for detecting shellfish toxins includes a shellfish tissue sample as the analyte, and the shellfish toxin includes at least one of scallop toxin, scallop toxin, oospermia toxin, or algal toxin.

[0038] The present invention also provides a method for detecting sulfonamide drugs, comprising the following steps: detecting the analyte using the electroextraction analysis method described above; The purifying agent includes magnesium sulfate, and the mass ratio of the analyte to the purifying agent is 10000:1 to 1:10; the solvent includes acetonitrile.

[0039] In one embodiment, in the method for detecting sulfonamide drugs, the extraction voltage is -8.5 to -6.5 kV, and the extraction time is 10-16 min.

[0040] In one embodiment, in the method for detecting sulfonamide drugs, the analyte includes animal meat, and the sulfonamide drug includes at least one of sulfathiazole, sulfamethhidiazole, sulfachlorpyridazine, sulfadiazine, sulfacetamide, or sulfadiazine.

[0041] Compared with the prior art, the present invention has the following beneficial effects: This invention discloses a diversion-in-situ matrix purification liquid-electrohydride extraction device, method, and application. The device reduces the risk of bubble generation and improves baseline stability and electro-extraction efficiency through diversion. The method achieves matrix purification and selective extraction by adding a purifying agent, thereby achieving highly efficient concentration and enrichment. It is simple to operate, low in cost, and provides excellent enrichment results. During extraction, the target analyte undergoes a continuous deceleration migration effect in the diversion tube and tends to stagnate, achieving regional enrichment and ultimately creating an enrichment zone. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the split-in-situ matrix purification solution-electrohydride extraction device of Example 1, wherein 10 is a high-voltage power supply, 20 is a precision injection pump, 30 is a syringe, 31 is an electrolytic fluid, 40 is a stainless steel electrode wire, 50 is a platinum double-ring electrode wire, 60 is a split tube, 70 is a sample bottle, and 71 is a sample solution. Figure 2 This is a schematic diagram of the state during the electro-extraction process of the split-in-situ matrix purification solution-electro-liquid extraction device in Example 1, where 50 is the upper and lower double ring electrode wire of platinum, 60 is the split tube, 70 is the sample bottle, 71 is the sample solution, and 72 is the target enrichment zone. Figure 3 The graph shows the current variation of different numbers of shunt pipes in Example 2 within 300s at 10kV, where Sample 1, Sample 2, Sample 3, and Sample 4 are parallel experiments under the same conditions. Figure 4 This is a graph showing the relationship between the crystal violet extraction rate and time for different numbers of split-channels in Example 2; Figure 5 This is a graph showing the relationship between the shellfish toxin extraction rate and time at -4kV for different numbers of diversion pipes in Example 3; Figure 6 This is a graph showing the relationship between the extraction rate of sulfonamide antibiotics and time at -7kV for different numbers of diversion pipes in Example 4. Detailed Implementation

[0043] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0044] It should be noted that when a component is said to be "fixed to" another component, it can be directly on the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0046] source: Unless otherwise specified, all reagents, materials, and equipment used in this embodiment are commercially available; unless otherwise specified, all test methods are conventional test methods in this field.

[0047] Example 1 A diversion-in-situ matrix purification liquid-electrohydride extraction device.

[0048] I. A schematic diagram of the device is shown below. Figure 1 As shown.

[0049] The device includes an extraction assembly and a sample assembly. The extraction assembly includes a push-pull device, a syringe electrode, and a shunt tube. The syringe electrode consists of a syringe electrode wire and a syringe. The push-pull device drives the syringe piston in a push-pull motion. One end of the syringe electrode wire is inserted into the tail of the syringe piston rod and protrudes through and is exposed at the rubber head of the piston rod, forming the structure of the "syringe electrode." The other end of the syringe electrode wire is connected to a grounded wire. The syringe inlet is connected to the shunt tube, and the other end of the shunt tube is immersed in the sample to be extracted.

[0050] In this embodiment, the syringe electrode wire is a stainless steel electrode wire, the push-pull device is a precision injection pump, and the syringe is injected with an electrolyte containing organic electrolytes and fixed on the precision injection pump.

[0051] The sample assembly includes a sample container and a sample electrode wire. One end of the sample electrode wire is connected to a power source, and the other end extends into the sample container containing the extractant and is immersed in the extractant.

[0052] In this embodiment, the sample container is a sample bottle, the sample electrode wire is a platinum double-ring electrode wire, and the power supply is a high-voltage power supply.

[0053] II. Assembly of the diversion-in-situ matrix purification solution-electrohydride extraction device.

[0054] 1. Insert the stainless steel electrode wire 40 into the piston rod of the syringe 30 and pass it through the rubber head on the piston rod to form a "syringe electrode" structure. Connect the stainless steel electrode wire 40 to the ground.

[0055] 2. Inject the conductive solution 31 containing electrolyte components into the syringe 30, and then fix the syringe 30 onto the precision injection pump 20; the conductive solution 31 is a methanol solution or a methanol-water solution with a volume fraction of 2:1, which contains a certain concentration of organic electrolyte; the organic electrolyte is 3 mmol / L malonic acid or other organic acids with similar acidity (e.g., at least one of phthalic acid, acetic acid, and formic acid) and 3 mmol / L triethylamine or other organic bases with similar basicity (e.g., at least one of triethylamine, diethylamine, and ammonium acetate).

[0056] 3. Use a Luer connector or hollow plastic cone to tightly connect the syringe 30 to one end of the shunt tube 60, and use the syringe pump 20 to fill the shunt tube 60 with conductive fluid.

[0057] 4. Insert the other end of the shunt tube 60 and the platinum upper and lower double ring electrode wire 50 connected to the high voltage power supply 10 into the sample bottle 70 containing the sample solution 71, and immerse them in the sample solution 71.

[0058] In this embodiment, the shunt tube 60 is made of insulating material, with a length of 40 cm and an inner diameter of 0.46 mm. The sample vial 70 is also made of insulating material, with a capacity of 10 mL, a height of 8 cm, and an inner diameter of 1.4 cm. The significant difference in cross-sectional area between the sample vial 70 and the shunt tube 60 facilitates faster permeation mass transfer within the sample vial while significantly suppressing diffusion mass transfer within the shunt tube, thus preventing the target substance from diffusing back into the vial.

[0059] The high-voltage power supply 10 is a positive high-voltage power supply of 0~30kV or a negative high-voltage power supply of -30~0kV. The stainless steel electrode wire 40 and the platinum double-ring electrode wire 50 both have a diameter of 0.5mm. The precision syringe pump 20 has a flow rate of 200μL / min, and the syringe capacity is 5mL or 10mL.

[0060] III. An electro-extraction analysis method.

[0061] Electro-extraction is performed using the above-described diversion-in-situ matrix purification solution-electro-liquid extraction device, and its schematic diagram is shown below. Figure 2 As shown. The specific steps are as follows.

[0062] 1. Preparation of the sample solution: Mix the sample with the purification agent, and use a polar solvent to extract the target analyte from the sample. The volume of the polar solvent is 3 mL.

[0063] 2. Preparation of standard series sample solutions: Mix the standard solution with the purification agent, and dilute the standard solution stepwise to obtain a series of standard solutions of known concentrations. Extract the target analyte using 3 mL of polar solvent.

[0064] In this embodiment, the purifying agent includes at least one of chitosan, magnesium sulfate, polyethylene glycol, C18, PSA, or chitin. The mass ratio of the sample or standard solution to the purifying agent is 10000:1 to 1:10 (the amount of purifying agent is selected based on the change in the extraction rate of the target analyte with the amount of purifying agent added; the amount of purifying agent added ranges from 0 to 100 mg, and a line graph is plotted between the extraction rate of the target analyte and the amount of purifying agent to select the optimal amount of purifying agent); the polar solvent includes at least one of methanol, acetonitrile, ethanol, ethyl acetate, isopropanol, and acetone. After immersing the platinum double-ring electrode wire and shunt tube of the electroextraction device into the standard sample solution, the power is turned on to begin electroextraction. After a certain period, the power is turned off, and a series of standard injection solutions of varying concentrations are obtained by using a syringe pump. The initial sample solution is as follows: Figure 2 As shown in state a.

[0065] 3. Assemble the electroextraction device. Immerse the shunt tube and platinum double-ring electrode wires in the sample solution. Adjust the voltage to 2~7kV or -7~-2kV, and turn on the power. At this time, the sample solution... Figure 2 As shown in state b; the electroextraction duration is 2~20 min; the sample solution at the end of extraction is as follows: Figure 2 As shown in state c, the target analyte is enriched within the tube, and the target analyte enrichment zone 72 is clearly visible, displaying the color of the target analyte. This zone is located away from the contact surface between the sample vial and the splitter tube. Extraction was then performed on the test sample solution and the standard series sample solutions, respectively.

[0066] 4. After extraction, if Figure 2 As shown in state d, the sample is directly coupled online for analysis and detection via a syringe pump, or 200 μL of the sample solution or standard solution (i.e., the target enrichment zone 72) is collected in the split tube and then analyzed.

[0067] 5. Compare the liquid chromatography spectrum of the enriched sample solution with the liquid chromatography spectrum or mass spectrum of each concentration of enriched standard solution. The characteristic peak of the corresponding component with the same retention time in the liquid chromatography spectrum of the enriched standard solution is the characteristic peak of the same substance. Calculate the content of the target substance in the sample based on the peak area of ​​the characteristic peak using the accompanying standard curve.

[0068] Example 2 Crystal violet in methanol was enriched by electro-extraction.

[0069] I. The instruments used in this embodiment include the split-in-situ matrix purification solution-electrohydride extraction device from Example 1, a 1 / 10000 electronic balance, a micropipette, an LC-20A high-performance liquid chromatograph (SPD-M20A diode array detector), and a SHIMADZU C18 column (250 × 4.6 mm, 5 μm). The reagents used are: methanol and acetonitrile (chromatographic grade), and malonic acid (analytical grade).

[0070] II. The number of pre-prepared branch pipes of varying quantities, according to... Figure 3 The time-current variation curves of single-channel (a), dual-channel (b), triple-channel (c), quadruple-channel (d), quintuple-channel (e), seven-channel (f), and eleven-channel (g) at 10kV over 300s show that when the number of split channels is 1 and 2, the current drops sharply during extraction due to bubble formation within the channels, forcing the electro-extraction process to stop. As the number of split channels increases, the electro-extraction process gradually stabilizes, and the current shows a steady downward trend over time. When the number of split channels reaches 11, the current hardly decreases during electro-extraction, which instead leads to a sharp decrease in electro-extraction efficiency. In the experiment on the extraction rate of crystal violet, as shown... Figure 4 As shown, the extraction rate is low when the number of split channels is 1. The extraction efficiency of crystal violet increases with the number of channels, but decreases when the number of channels reaches 11. Therefore, 5 channels were ultimately chosen as the optimal number of split channels.

[0071] III. Sample to be tested in this embodiment: Methanol suspected of being contaminated with crystal violet; Standard: Crystal violet, analytical grade, purchased from Shanghai Maclean Biochemical Technology Co., Ltd., batch number CAS: 548-62-9.

[0072] Weigh 100 mg of crystal violet into a 100 mL volumetric flask, dilute to the mark with methanol, and shake well to prepare a 1000 μg / L crystal violet standard solution.

[0073] The crystal violet of methanol was enriched by electroextraction using the diversion-in-situ matrix purification solution-electrohydride extraction device of Example 1. The specific steps are as follows: 1. Prepare the injection solution for the sample to be tested.

[0074] Assemble the electroextraction apparatus. Add 3 mL of the methanol to be tested to the sample vial, shake well, and prepare the sample solution. Immerse the platinum double-ring electrode wire and shunt of the electroextraction apparatus into the sample solution, adjust the voltage to +5 kV, and turn on the power to begin electroextraction. After 10 minutes, turn off the power and collect 200 μL of the sample solution in the shunt using a syringe pump.

[0075] 2. Prepare the standard injection solution.

[0076] Assemble the electroextraction apparatus. Then, serially dilute the crystal violet standard solution to prepare a series of standard sample solutions with concentrations of 0, 200, 400, 600, 800, and 1000 μg / L. Immerse the platinum double-ring electrode wire and shunt of the electroextraction apparatus into the standard sample solutions, adjust the voltage to +5 kV, and turn on the power to start electroextraction. After 10 minutes, turn off the power and collect 200 μL of solution in the shunt using a syringe pump to obtain a series of standard injection solutions.

[0077] 3. High performance liquid chromatography detection.

[0078] Mobile phase: By volume ratio, the mobile phase consists of 60% phase A and 40% phase B.

[0079] Phase A is acetonitrile, and Phase B is an aqueous solution of 5 mmol / L ammonium acetate + 0.1% formic acid. Phase B is prepared by the following method: 0.771 g of ammonium acetate is weighed using a 1 / 1000 electronic balance and placed in a 500 mL volumetric flask. After dissolving in 400 mL of water, 0.5 mL of formic acid is added, and the solution is brought to a final volume of 500 mL. The solution is then filtered and degassed by sonication for later use.

[0080] High performance liquid chromatography (HPLC) detection conditions: flow rate 1.0 mL / min, injection volume 10 μL. Crystal violet detection wavelength: 588 nm.

[0081] 4. Data processing.

[0082] After the system is balanced, the sample solution to be tested and a series of standard solutions of different concentrations are injected separately, and the chromatograms of the sample solution and the standard solution are recorded.

[0083] A scatter plot of crystal violet standard injection solutions was created, with the peak area of ​​each standard injection solution as the ordinate and the concentration of the standard injection solution as the abscissa. A two-variable linear regression analysis was then performed on the scatter plots regarding the peak area and concentration of each standard injection solution to obtain the standard curve equation, where x is the concentration of the standard injection solution (μg / L) and y is the peak area (mAU). s), a and b are constants; the elution position of the sample injection is determined based on the retention time of the peak of the standard injection solution, and the peak area of ​​the sample injection solution is substituted into the above relevant equations for calculation to obtain the crystal violet content in the sample to be tested.

[0084] After testing and calculation, the crystal violet content in the sample tested in this embodiment was 816 μg / L.

[0085] Example 3 I. The instruments used in this embodiment include the split-in-situ matrix purification solution-electrohydride extraction device of Example 1, a 1 / 1000 electronic balance, a 1 / 10000 electronic balance, a 50 mL graduated cylinder, a micropipette, a Vortex-Genie adjustable vortex mixer, a Milli-Q ELement ultrapure water treatment system, a CT15RT benchtop centrifuge, an LC-20A high-performance liquid chromatograph, a 4000 QTRAP® triple quadrupole mass spectrometer, and a Poroshell 120 SB C18 column (100 mm × 4.6 mm, 2.7 μm, Agilent Technologies).

[0086] The reagents used are: methanol, acetonitrile, triethylamine (chromatographic grade); malonic acid (analytical grade).

[0087] II. The number of pre-prepared branch pipes of varying quantities, according to... Figure 5 The time-extraction rate curves at -4 kV for single-channel (a), dual-channel (b), triple-channel (c), quadruple-channel (d), quintuple-channel (e), seven-channel (f), and eleven-channel (g) show that, compared to other pathways, when the number of split channels is 5, all four shellfish toxins reach exhaustion extraction in a very short time and have good stability. Therefore, 5 channels were selected as the optimal number of split channels.

[0088] III. The sample to be tested in this embodiment is: Shellfish samples to be tested: Shellfish samples suspected of containing shellfish toxins; Blank shellfish samples: Normal shellfish samples without shellfish toxins; Standards: Dinophysistoxin-1 (DTX1), Okadaicacid (OA), Yessotoxin (YTX), and 1-Homoyessotoxin (hYTX) were purchased from the National Research Centre of Canada.

[0089] The extraction of shellfish toxins from shellfish samples using the split-in-situ matrix purification solution-electrohydride extraction device of Example 1 includes the following steps: 1. Prepare the injection solution for the sample to be tested.

[0090] Assemble the electroextraction apparatus. Accurately weigh 20 mg of shellfish sample into a 10 mL polypropylene tube, add 40 μL of water, vortex mix for 60 s, then add 70 mg of chitosan and 3 mL of acetonitrile, sonicate for 10 min, and centrifuge at 13000 rpm for 5 min. Immerse the upper and lower double-ring electrode wires of the cathode and the Teflon tube into the sample solution for electroextraction. Set the high-voltage power supply parameters to -4 kV and the precision syringe pump flow rate to 200 μL. After electroextraction for 15 min with the high-voltage power supply turned on, turn off the power supply and run the syringe pump to collect 200 μL of the receiving phase solution in the Teflon tube into a glass liner tube, mix well, and then perform LC-MS / MS detection.

[0091] 2. Prepare the standard injection solution.

[0092] Assemble the electroextraction apparatus. Prepare a series of standard solutions with concentrations of 0, 10, 20, 30, 40, 50, 60, and 70 μg / kg by adding a standard solution of shellfish toxins to 10 mL centrifuge tubes. Add 60 μL of water, vortex for 60 s, then add 70 mg of chitosan and 3 mL of acetonitrile, sonicate for 10 min, and centrifuge at 13000 rpm for 5 min. Immerse the upper and lower double-ring electrode wires of the cathode and the Teflon tube into the sample solution for electroextraction. Set the high-voltage power supply parameters to -4 kV and the precision syringe pump flow rate to 200 μL. After electroextraction for 15 min with the high-voltage power supply turned on, turn off the power and run the syringe pump to collect 200 μL of the receiving phase solution from the Teflon tube into a glass liner tube, mix well, and perform LC-MS / MS analysis. Obtain a series of standard injection solutions at various concentrations.

[0093] 3. Detection using liquid chromatography-mass spectrometry.

[0094] Mobile phase: The mobile phase consists of acetonitrile (A) and an aqueous solution of 10 mmol / L ammonium formate containing 0.1% formic acid (B). Phase B is prepared by the following method: 0.315 g of ammonium formate is accurately weighed using a 1 / 1000 electronic balance, dissolved in ultrapure water, transferred to a 500 mL volumetric flask, 500 μL of formic acid is added, and the solution is diluted to the mark with ultrapure water. After filtration, the solution is degassed by sonication and set aside for later use.

[0095] Liquid chromatography detection conditions: flow rate 0.4 mL / min, injection volume 35 μL, column temperature 40℃.

[0096] Mass spectrometry detection conditions: Ionization mode was negative ion mode, and scanning mode was multiple reaction monitoring (MRM). Collision gas (CAD): medium, curtain gas (CUR): 15.0 psi, ionization voltage (IS): -4200.0 V, ion source temperature (TEM): 500.0 °C, nebulizer gas (GS1): 60.0 psi, heating gas (GS2): 50.0 psi, inlet voltage (EP): -10.0 V, collision chamber outlet voltage (CXP): -15.0 V. The corresponding declustering voltage, collision energy, precursor ion, and product ion for each other analyte are listed in the table below. The residence time for all analytes was set to 100 ms.

[0097] Table 1. Chromatographic retention time, precursor ion, daughter ion, declustering voltage, and collision energy parameters of the target analyte.

[0098] a. Used for quantitative analysis 4. Data processing.

[0099] After the system is balanced, the sample solution to be tested and a series of standard solutions of different concentrations are injected separately.

[0100] By inputting the concentrations of the series of standard solutions into the software, the peak area-concentration standard curve equation can be obtained, and the software can calculate the content of each shellfish toxin component in the sample to be tested.

[0101] Results: The concentration of datian linuric acid in the shellfish samples was 99.3 μg / kg, the concentration of fin algae toxin was 37.4 μg / kg, and no other shellfish toxins were detected.

[0102] Furthermore, to further demonstrate the effectiveness and accuracy of this method for detecting the aforementioned shellfish toxins, the limits of detection (LOD), lower limits of quantitation (LQ), accuracy, and precision of each shellfish toxin in shellfish samples were evaluated according to the validation guidelines for analytical methods in EU Food Safety Regulation 2021 / 808 / EC (European Commission 2021). The LOD was calculated for samples with a signal-to-noise ratio (SNR) of 3, and the LQ was calculated for shellfish samples with a SNR of 10. The LOD and LQ for shellfish samples are summarized in Table 2. Accuracy and precision were evaluated by calculating intra-day and inter-day recoveries and relative standard deviations (RSDs). Inter-day differences were obtained from the determination of six parallel samples at three concentrations on the same day, and intra-day differences were obtained from the parallel determination of six parallel samples at three concentrations per day for three days, as shown in Table 3.

[0103] Table 2. Limits of detection and lower limits of quantification for shellfish toxins extracted by electroextraction.

[0104] Table 3. Accuracy and precision data of electro-extraction of shellfish toxins from shellfish samples.

[0105] Example 4 I. The instruments used in this embodiment include the split-in-situ matrix purification solution-electrohydride extraction device of Example 1, a 1 / 1000 electronic balance, a 50 mL graduated cylinder, a micropipette, a Vortex-Genie adjustable vortex mixer, a Milli-Q ELement ultrapure water treatment system, a CT15RT benchtop centrifuge, an LC-20A high-performance liquid chromatograph, a 4000 Q TRAP® triple quadrupole mass spectrometer, and a Poroshell 120 SB C18 column (100 mm × 4.6 mm, 2.7 μm, Agilent Technologies).

[0106] The reagents used are: methanol, acetonitrile, triethylamine (chromatographic grade); malonic acid (analytical grade).

[0107] II. The number of different pre-prepared branch pipes, the number of different pre-prepared branch pipes, according to Figure 6 The time-extraction rate curves at -7KV for single-channel (a), dual-channel (b), triple-channel (c), quadruple-channel (d), quintuple-channel (e), seven-channel (f), and eleven-channel (g) show that, compared to other pathways, when the number of split channels is 5, all six sulfonamide antibiotics reach exhaustion extraction in a very short time and have good stability. Therefore, 5 channels are selected as the optimal number of split channels.

[0108] III. The sample to be tested in this embodiment is: Meat samples to be tested: meat samples suspected of containing sulfonamide antibiotic residues; blank meat samples: normal meat samples without sulfonamide antibiotic residues; standards: sulfathiazole (STZ), sulfamethizole (SMT), sulfachloropyridazine (SCP), sulfaphenazolum (SPZ), sulfacetamide (SFM), and sulfisoxazole (SSZ) were purchased from Beijing Mairuida Technology Co., Ltd.

[0109] The extraction of sulfonamide antibiotics from meat samples using the split-in-situ matrix purification solution-electrohydride extraction device of Example 1 includes the following steps: 1. Prepare the injection solution for the sample to be tested.

[0110] Assemble the electroextraction apparatus. Accurately weigh 20 mg of meat sample into a 10 mL polypropylene tube, vortex to mix for 1 min, then add 30 mg of anhydrous magnesium sulfate and 3 mL of acetonitrile, sonicate for 7 min, and centrifuge at 13000 rpm for 5 min. Immerse the upper and lower double-ring electrode wires of the cathode and the Teflon tube into the sample solution for electric field-assisted extraction, extracting at -8 kV high voltage for 15 min. After turning off the power, run the syringe pump to collect 200 μL of the receiving phase solution from the Teflon tube into a glass liner tube, mix well, and then perform LC-MS / MS detection.

[0111] 2. Prepare the standard injection solution.

[0112] Assemble the electroextraction apparatus. A series of standard solutions with concentrations of 0, 1, 2, 3, 4, 5, 6, and 7 μg / kg were prepared by adding a standard solution of sulfonamide antibiotics to 10 mL centrifuge tubes. The solutions were vortexed for 60 s, then 30 mg of anhydrous magnesium sulfate and 3 mL of acetonitrile were added. The mixture was sonicated for 7 min and centrifuged at 13000 rpm for 5 min. The upper and lower double-ring electrode wires of the cathode and the Teflon tube were immersed in the sample solution for electric field-assisted extraction at -8 kV for 15 min. After turning off the power, the syringe pump was run, and 200 μL of the receiving phase solution from the Teflon tube was collected in a glass liner tube. After mixing, the solution was analyzed by LC-MS / MS to obtain a series of standard injection solutions at various concentrations.

[0113] 3. Detection using liquid chromatography-mass spectrometry.

[0114] Mobile phase: The mobile phase consists of acetonitrile (A) and an aqueous solution of 20 mmol / L ammonium acetate containing 0.1% formic acid (B). Phase B is prepared by the following method: 0.771 g of ammonium acetate is accurately weighed using a 1 / 1000 electronic balance, dissolved in ultrapure water, transferred to a 500 mL volumetric flask, 500 μL of formic acid is added, and the solution is diluted to the mark with ultrapure water. The solution is then filtered and degassed by sonication for later use.

[0115] Liquid chromatography detection conditions: flow rate 0.4 mL / min, injection volume 10 μL, column temperature 40℃.

[0116] Mass spectrometry detection conditions: Ionization mode was positive ion mode, and scanning mode was multiple reaction monitoring (MRM). Collision gas (CAD): medium, curtain gas (CUR): 10.0 psi, ionization voltage (IS): 5500.0 V, ion source temperature (TEM): 400.0 °C, nebulizer gas (GS1): 60.0 psi, heating gas (GS2): 60.0 psi, inlet voltage (EP): 10.0 V, collision chamber outlet voltage (CXP): 15.0 V. The corresponding declustering voltage, collision energy, precursor ion, and product ion for each other analyte are listed in Table 4. The residence time for all analytes was set to 100 ms.

[0117] Table 4. Chromatographic retention time, parent ion, daughter ion, declustering voltage, and collision energy parameters of the target analyte.

[0118] a. Used for quantitative analysis 4. Data processing.

[0119] After the system is balanced, the sample solution to be tested and a series of standard solutions of different concentrations are injected separately.

[0120] By inputting the concentrations of the series of standard solutions into the software, the peak area-concentration standard curve equation can be obtained, and the content of each sulfonamide antibiotic in the sample to be tested can be calculated by the software.

[0121] Results: No sulfonamide antibiotics were detected in the meat samples tested.

[0122] In addition, to further demonstrate the effectiveness and accuracy of this method for the detection of sulfonamide antibiotics, the limits of detection (LOD), lower limits of quantitation (LQ), accuracy, and precision of each sulfonamide antibiotic in meat samples were evaluated according to the analytical method validation guidelines of EU Food Safety Regulation 2021 / 808 / EC (European Commission 2021). The LOD of the sample was calculated based on the concentration value of the sample with a signal-to-noise ratio (SNR) of 3, and the LQ of the meat sample was calculated based on the concentration value of the meat sample with a SNR of 10. The LOD and LQ of the meat samples are summarized in Table 5. Accuracy and precision were evaluated by calculating the intra-day and inter-day recoveries and relative standard deviations (RSDs). The inter-day difference was obtained from the determination of six parallel samples of three concentrations on the same day, and the intra-day difference was obtained from the parallel determination of six parallel samples of three concentrations per day for three days, as shown in Table 6.

[0123] Table 5. Limits of detection and lower limits of quantitation for sulfonamide antibiotics obtained by electroextraction.

[0124] Table 6. Accuracy and precision data of electroextraction of sulfonamide antibiotics in meat samples

[0125] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0126] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A diversion-in-situ matrix purification solution-electrohydride extraction device, characterized in that, include: The extraction assembly includes a push-pull device, a syringe electrode, and a shunt tube. The syringe electrode includes a connected syringe electrode wire and a syringe. The syringe is used to contain an electrolytic fluid. The push-pull device drives the piston of the syringe to perform a push-pull movement. One end of the syringe electrode wire is connected to the syringe, and the other end is grounded or connected to a power source. All syringe electrode wires converge and are grounded or connected to a power source together. The shunt tube has ≥3 channels. One end of each shunt tube is connected to its corresponding syringe, and the other end is used to immerse the same extractant. as well as The sample assembly includes a sample container and a sample electrode wire; when the other end of the syringe electrode wire is grounded, one end of the sample electrode wire is used to immerse the extractant and the other end is used to connect to a power source; when the other end of the syringe electrode wire is connected to a power source, one end of the sample electrode wire is used to immerse the extractant and the other end is used to ground; the sample container is used to hold the extractant.

2. The diversion-in-situ matrix purification liquid-electrohydride extraction device according to claim 1, characterized in that, One end of the syringe electrode wire is inserted into the tail of the syringe piston rod and exposed at the head of the piston rod.

3. A method for diversion-in-situ matrix purification solution-electrohydride extraction, characterized in that, Includes the following steps: Prepare the extractant and the standard, and use the split-in-situ matrix purification liquid-electrohydride extraction device according to any one of claims 1 to 2 to perform electro-extraction on the extractant and the standard to obtain the test sample and the standard sample. The sample to be tested is enriched in the shunt tube; The step of preparing the extractant includes: mixing the sample with a purifying agent and extracting it with a solvent to obtain the extractant; The steps for preparing the standard include: mixing the standard solution with a purifying agent, extracting it with a solvent, and obtaining the standard.

4. The method for diversion-in-situ matrix purification solution-electrohydride extraction according to claim 3, characterized in that, The conditions for electro-extraction include: immersing the shunt tube and sample electrode wire into the substance to be extracted, using an extraction voltage of -100kV to 100kV, wherein the extraction voltage is not 0, and an extraction time of ≤200min.

5. The method for diversion-in-situ matrix purification solution-electrohydride extraction according to claim 3, characterized in that, The purifying agent includes at least one of silica gel, porous carbon materials, metal oxides, metal salts, metal-organic frameworks, covalent organic frameworks, microporous organic polymers, ionic liquids, eutectic solvents, supramolecular solvents, surfactants, adsorption resins, molecularly imprinted polymers, magnetic nanomaterials, melamine sponges, hydrogels, metal hydroxides, metal complexes, complexing agents, cyclodextrins, or urea, and the mass ratio of the sample or standard solution to the purifying agent is 10000:1 to 1:10; The solvents include methanol, acetonitrile, ethanol, water, ethyl acetate, butyl acetate, isoamyl acetate, isopropyl acetate, benzoyl acetate, isoborneol acetate, bornyl acetate, linalyl acetate, geraniol acetate, cinnamyl acetate, ethyl benzoate, methyl benzoate, butyl benzoate, isoamyl benzoate, isopropyl benzoate, isopropanol, n-butanol, tert-butanol, isoamyl alcohol, benzyl alcohol, higher fatty alcohols, dimethyl ether, methyl tert-butyl ether, tetrahydrofuran, diethyl ether, benzaldehyde, cinnamaldehyde, vanillin, citral, dichloromethane, chloroform, carbon tetrachloride, n-hexane, n-heptane, n-octane, isooctane, cyclohexane, methylcyclohexane, petroleum ether, fatty acids, ammonia, dimethyl ether. At least one of the following: sulfone, butanone, trifluoroacetic acid, ethyl trifluoroacetate, methyl trifluoroacetate, isopropyl trifluoroacetate, isobutyl trifluoroacetate, isoamyl trifluoroacetate, isohexyl trifluoroacetate, isohexyl trifluoroacetate, isooctyl trifluoroacetate, isodecyl trifluoroacetate, ethylene glycol trifluoroacetate, propylene glycol trifluoroacetate, butyl trifluoroacetate, pentanediol trifluoroacetate, hexanediol trifluoroacetate, octanediol trifluoroacetate, decanediol trifluoroacetate, pentaerythritol trifluoroacetate, sorbitol trifluoroacetate, mannitol trifluoroacetate, dimethylformamide, pyridine, benzene, toluene, carbon disulfide, dimethyl carbonate, diethyl carbonate, 1,4-dioxane, and acetone; The conductive solution for electroextraction includes a conductive solvent and an electrolyte. The concentration of the electrolyte in the conductive solution is 0~1 mol / L, and the electrolyte includes an acid, a base, or a salt.

6. An electro-extraction analysis method, characterized in that, The method includes the following steps: extracting the analyte using the split-in-situ matrix purification solution-electrohydride extraction method as described in any one of claims 3-5 to obtain the analyte sample or standard sample, analyzing and detecting it using an online coupled analysis device, or collecting it into a container for analysis and detection, and comparing the obtained spectra.

7. The application of the electroextraction analysis method according to claim 6 in the detection of shellfish toxins and / or sulfonamides.

8. A method for detecting shellfish toxins, characterized in that, The method includes the following steps: detecting the analyte using the electroextraction analysis method described in claim 6; The purifying agent includes chitosan, and the mass ratio of the analyte to the purifying agent is 10000:1 to 1:10; the solvent includes acetonitrile.

9. A method for detecting sulfonamide drugs, characterized in that, The method includes the following steps: detecting the analyte using the electroextraction analysis method described in claim 6; The purifying agent includes magnesium sulfate, and the mass ratio of the analyte to the purifying agent is 10000:1 to 1:10; the solvent includes acetonitrile.

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