Electrochemical-mass spectrometry device and method for synchronously acquiring chemical information of inorganic and organic components in PM2.5

Abstract

The invention discloses an electrochemical-mass spectrometry analysis method for synchronously acquiring chemical information of inorganic and organic components in PM2.5, and relates to the field of analysis. A strategy of combining online extraction of components of a to-be-detected object and real-time detection of two mass spectrometers is adopted; the electrospray ionization device is coupled with the two mass spectrometers; collected PM2.5 is placed in the device, water-soluble, fat-soluble, indissolvable, oxidizable, reducible and other different components in PM2.5 are subjected to online extraction and ionization by means of solvent extraction, complex reaction, electrochemical oxidation and electrochemical reduction, and then the components are transmitted to two linear ion trap mass spectrometers to be simultaneously detected in real time in positive and negative modes; and the problems of complicated operation, long time consumption, loss and pollution of an object to be detected and the like in offline extraction are avoided.

Description

Technical Field

[0001] The present invention relates to the field of analysis technology, and in particular to an electrochemical-mass spectrometry analysis method for synchronously acquiring chemical information of inorganic and organic components in PM2.5. Background Art

[0002] PM2.5 can enter people's lungs through the respiratory system, further migrate to the blood system, and even appear in the brain, causing an increase in the incidence of circulatory, respiratory, cardiovascular, and nervous system diseases. PM2.5 contains extremely complex chemical components, which accumulate chemical pollutants from the local environment, including but not limited to heavy metals (such as lead, cadmium, and chromium), anions (such as NO 2- 、NO 3- , Cl - 、SO4 2- and CO3 2- ) and organic species (such as polycyclic aromatic hydrocarbons, organic acids and organic amines). These chemicals are key components of PM2.5 that are harmful to human health and are indicative substances of pollution sources. Detailed PM2.5 chemical composition analysis can achieve higher accuracy in assessing related health risks and tracing pollution sources.

[0003] At present, the analysis strategy for multiple components in PM2.5 generally combines two key steps: offline extraction and detection. In general, in order to analyze the various components present in PM2.5 (such as organic acids, metal compounds), different sample pretreatments are required for the corresponding components. Therefore, it is necessary to divide the collected PM2.5 into multiple parts, and adopt different extraction methods to obtain the test liquid according to the different properties of the target detection object. Then, the corresponding detection technology is selected for the target detection object for detection. For example, ion chromatography, atomic emission spectroscopy, atomic absorption spectroscopy, or inductively coupled plasma mass spectrometry, gas chromatography-mass spectrometry, high performance liquid chromatography-mass spectrometry, etc.

[0004] Analytical techniques such as Fourier transform infrared spectroscopy, X-ray crystallography, scanning electron microscopy-energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy have also been tried for the analysis of PM2.5.

[0005] Therefore, up to now, there is no analytical method that can achieve one-time acquisition of information on all chemical species in PM2.5. The above-mentioned "offline extraction and detection" analysis strategy has the following disadvantages:

[0006] (1) The offline extraction process is complicated and time-consuming. In addition, there are risks such as loss and contamination of the analyte during the extraction process, which increases the factors that affect the accuracy of the measurement.

[0007] (2) The offline extraction process requires a large amount of sample, which is not conducive to the analysis of small samples (e.g., in the milligram range);

[0008] (3) The differences between the sample and the test solution obtained by offline pretreatment make it difficult to elucidate the physical and chemical relationships between chemical species in PM2.5.

[0009] (4) After offline extraction, the detection of the test liquid requires the selection of corresponding detection technology according to the type of the test object, which means that multiple detection instruments are required for joint analysis, which is costly.

[0010] Analytical techniques such as Fourier transform infrared spectroscopy, X-ray crystallography, scanning electron microscopy-energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy do not require sample pretreatment to analyze PM2.5, but these methods cannot provide quantitative and qualitative information for organic and inorganic chemical components at the same time. Summary of the invention

[0011] The purpose of the present invention is to solve at least one of the technical problems existing in the prior art and to provide an electrochemical-mass spectrometry analysis method for synchronously acquiring chemical information of inorganic and organic components in PM2.5.

[0012] The technical solution of the present invention is as follows:

[0013] An electrochemical-mass spectrometry analysis device for synchronously acquiring chemical information of inorganic and organic components in PM2.5, comprising a first channel, a second channel and a third channel connected by a three-way connector;

[0014] It also includes a liquid storage bottle and an electrolytic cell, wherein the liquid storage bottle is connected to the electrolytic cell via a six-way valve and a peristaltic pump in sequence, and the electrolytic cell is connected to the first channel;

[0015] The electrolytic cell comprises a working electrode, a reference electrode and a counter electrode. The working electrode is provided with a conductive film, which is connected to an electrochemical workstation via a Pt wire. A filter membrane is attached to the conductive film, and PM2.5 particles are collected on the filter membrane.

[0016] The second channel and the third channel are connected to the first mass spectrometer and the second mass spectrometer respectively. Electrospray ionization devices are arranged between the second channel and the first mass spectrometer and between the third channel and the second mass spectrometer.

[0017] As a preferred embodiment of the present invention, the electrospray ionization device comprises a metal tube capable of applying voltage, both ends of the metal tube are connected to the capillary, and the metal tube is exposed.

[0018] As a preferred solution of the present invention, the second channel and the third channel both use capillaries of the same length.

[0019] As a preferred solution of the present invention, the three-way joint is made of metal and is grounded.

[0020] As a preferred embodiment of the present invention, the atomization gas pressures of the electrospray ionization devices are the same.

[0021] As a preferred solution of the present invention, the flow rates of the second channel and the third channel are the same.

[0022] The present invention also discloses an electrochemical-mass spectrometry analysis method for synchronously acquiring chemical information of inorganic and organic components in PM2.5, which is applied to any of the above-described devices, wherein a filter membrane collecting PM2.5 particles is attached to a conductive surface of a conductive membrane, and the solvents in a liquid storage bottle are first transported to an electrolytic cell one by one via a peristaltic pump, and water-soluble components, fat-soluble components and poorly soluble components in PM2.5 particles are extracted and complexed in turn, and oxidizable and reducible metal compounds in PM2.5 particles are extracted in turn via electrochemical oxidation and reduction of an electrochemical workstation; then, the analytes extracted by complexation with substances added in the second channel and the third channel are ionized by an electrospray ionization device, and sent to a mass spectrometer for detection and analysis.

[0023] As a preferred embodiment of the present invention, there are three liquid storage bottles, each containing water, methanol and EDTA-2Na aqueous solution;

[0024] The second channel is fed with EDTA-2Na solution;

[0025] The third channel is filled with silver nitrate solution.

[0026] As a preferred embodiment of the present invention, the following steps are included:

[0027] S1: At t=t0, the peristaltic pump is started to pump water into the electrolytic cell to extract the water-soluble components in the PM2.5 sample; the water-soluble components are divided into two equal parts, one of which is mixed with the EDTA-2Na introduced into the second channel, the metal ions in the aqueous solution component are complexed with EDTA-2Na to form an M-EDTA complex, and the organic acid in the water-soluble component is ionized by the electrospray ionization device and enters the first mass spectrometer for detection in the negative ion mode; the organic amine substances in the other equal part of the aqueous solution component are mixed with the AgNO3 introduced into the third channel, and after ionization by the electrospray ionization device, enter the second mass spectrometer for detection in the positive ion mode;

[0028] After the mass spectrometry signal of the water-soluble component drops to the baseline level t=t1, the peristaltic pump is started to pump methanol into the electrolytic cell to extract the fat-soluble component, and the fat-soluble component is divided into two equal parts; one equal part of the fat-soluble component is mixed with EDTA-2Na in the second channel, and the fat-soluble organic acid is detected in the negative ion mode of the first mass spectrometer; the other equal part of the fat-soluble component is mixed with AgNO3 in the third channel, and the polycyclic aromatic hydrocarbons are complexed with AgNO3 to form Ag-PAHs complexes, which are detected by mass spectrum in the positive ion mode of the second mass spectrometer;

[0029] When the MS signal of the fat-soluble component drops to the baseline t=t2, the peristaltic pump is started to pump the EDTA-2Na solution into the electrolytic cell to extract the sparingly soluble metal substances, and the sparingly soluble metal components are divided into two equal parts, one of which is mixed with the EDTA-2Na in the second channel, and the M-EDTA complex formed by the complexation of the sparingly soluble metal ions and EDTA-2Na is ionized by an electrospray ionization device and enters the first mass spectrometer for detection in the negative ion mode; the other is mixed with the silver nitrate solution in the third channel, and is ionized by an electrospray ionization device and enters the second mass spectrometer for detection in the positive ion mode;

[0030] After the mass spectrometry signal of the sparingly soluble metal component drops to the baseline t=t3, an EDTA-2Na aqueous solution is used as an electrolyte, a voltage is applied using an electrochemical workstation, and an electro-oxidation method is used to extract the oxidizable metal components in PM2.5; the oxidizable metal component is divided into two equal parts, one of which is mixed with the EDTA-2Na in the second channel, and the M-EDTA complex formed by the complexation of the oxidizable metal ions and EDTA-2Na is detected in the first mass spectrometer in the negative ion mode via an electrospray ionization device; the other equal part of the oxidizable metal component is mixed with the silver nitrate solution in the third channel, ionized by the electrospray ionization device, and entered into the second mass spectrometer in the positive ion mode for detection;

[0031] After the mass spectrometry signal of the oxidizable metal component drops to the baseline t=t4, the EDTA-2Na aqueous solution is still used as the electrolyte, the voltage is applied by the electrochemical workstation, and the reducible metal component is extracted by the electric reduction method; the reducible metal component is divided into two equal parts, one equal part of the reducible metal component is mixed with the EDTA-2Na in the second channel, and the M-EDTA complex formed by the complexation of the reducible metal ion and the EDTA-2Na is detected in the first mass spectrometer in the negative ion mode by an electrospray ionization device, and the other equal part of the reducible metal component is mixed with the silver nitrate solution in the third channel, ionized by the electrospray ionization device and entered into the second mass spectrometer in the positive ion mode for detection;

[0032] When the MS signal of the reducible metal component drops to the baseline at t=t5, the entire analysis procedure is completed.

[0033] The beneficial effects of the present invention are:

[0034] The analysis method of the present invention adopts a strategy combining online extraction of the components of the analyte and real-time detection by two mass spectrometers. At the same time, a special electrochemical ionization device for PM2.5 analysis is provided, which is coupled to two mass spectrometers. The collected PM2.5 is placed in the device, and the different components such as water-soluble, fat-soluble, poorly soluble, oxidizable and reducible components in PM2.5 are extracted and ionized online by means of solvent extraction, complex reaction, electrochemical oxidation and electrochemical reduction, and then transmitted to two linear ion trap mass spectrometers for real-time detection in positive and negative modes at the same time. The analysis method has the following advantages:

[0035] 1. Online extraction of target objects avoids the problems of offline extraction, such as complicated operation, long time consumption, loss of objects to be detected, and contamination;

[0036] 2. The required sample volume is small, only milligram level is needed;

[0037] 3. In addition to providing qualitative and quantitative information on chemical components, the online synchronous analysis of two mass spectrometers can also construct the physical and chemical relationship between chemical components based on the ion flow diagram of the target object.

[0038] 4. The detection of two mass spectrometers in positive and negative ion modes can simultaneously obtain qualitative and quantitative information of metal ions, anions, and organic matter, simplifying the detection process. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of the structure of a preferred embodiment of the present invention; wherein, 1-liquid storage bottle, 2-six-way valve, 3-peristaltic pump, 4-electrolytic cell, 5-first channel, 6-second channel, 7-third channel, 8-first mass spectrometer, 9-second mass spectrometer, 10-filter membrane, 11-conductive membrane, 12-electrospray ionization device, 13-metal tube;

[0040] Figure 2 is an analysis flow chart of a preferred embodiment of the present invention;

[0041] Figure 3 This is the ion current diagram of a mixed sample of standards with different forms analyzed by electrochemical mass spectrometry of the present invention. DETAILED DESCRIPTION

[0042] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. If no specific techniques or conditions are specified in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used that do not specify the manufacturer are all conventional products that can be obtained commercially.

[0043] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but it cannot be understood as a limitation on the scope of protection of the present invention.

[0044] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0045] In the description of the present invention, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood as not including the number itself, and "above", "below", "within" etc. are understood as including the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0046] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0047] Reference Figures 1 to 3 , the first embodiment of the present invention:

[0048] An electrochemical-mass spectrometry analysis device for synchronously acquiring chemical information of inorganic and organic components in PM2.5, comprising a first channel 5, a second channel 6 and a third channel 7 connected by a three-way connector;

[0049] It also includes a liquid storage bottle 1 and an electrolytic cell 4, wherein the liquid storage bottle 1 is connected to the electrolytic cell 4 via a six-way valve 2 and a peristaltic pump 3 in sequence, and the electrolytic cell 4 is connected to the first channel 5;

[0050] The electrolytic cell 4 includes a working electrode, a reference electrode and a counter electrode. The working electrode has a conductive film 11, which is connected to the electrochemical workstation via a Pt wire. A filter membrane 10 is attached to the conductive film 11, and PM2.5 particles are collected on the filter membrane 10.

[0051] The second channel 6 and the third channel 7 are connected to the first mass spectrometer 8 and the second mass spectrometer 9 respectively. An electrospray ionization device 12 is provided between the second channel 6 and the first mass spectrometer 8 and between the third channel 7 and the second mass spectrometer 9.

[0052] As a preferred embodiment of the present invention, it may also have the following additional technical features:

[0053] The electrospray ionization device 12 comprises a metal tube 12 to which a high voltage can be applied. Both ends of the metal tube 12 are connected to the capillary, and the metal tube is exposed.

[0054] The three-way connector is made of metal and is grounded to prevent voltage interference between the electrochemical workstation and the two mass spectrometers.

[0055] The second channel 6 and the third channel 7 both use capillaries of the same length, and more specifically, the pipe connections of the entire device all use capillaries. The atomization gas pressure of the electrospray ionization device 12 is the same. The flow rates of the second channel 6 and the third channel 7 are the same, so that the solution separated in the first channel 5 can reach the two electrospray ionization devices 12 at the same time, so as to ensure that the two mass spectrometers in the positive and negative ion detection modes simultaneously detect the chemical substances extracted in PM2.5 in real time.

[0056] The present invention also provides another embodiment, an electrochemical-mass spectrometry analysis method for synchronously obtaining chemical information of inorganic and organic components in PM2.5, which is applied to a device such as the first embodiment, wherein a filter membrane 10 collecting PM2.5 particles is attached to a conductive surface of a conductive membrane 11, and the solvent in the liquid storage bottle 1 is first transported to the electrolytic cell one by one through a peristaltic pump, and the water-soluble components, fat-soluble components and insoluble components in the PM2.5 particles are extracted and complexed in turn, and the oxidizable and reducible metal compounds in the PM2.5 particles are extracted in turn through electrochemical oxidation and reduction of an electrochemical workstation; then, the analytes extracted by complexation with substances added in the second channel and the third channel are ionized by an electrospray ionization device 12, and sent to a mass spectrometer for detection and analysis.

[0057] The liquid storage bottles 1 are provided with three, respectively containing water, methanol and EDTA-2Na solution;

[0058] The second channel 6 is fed with EDTA-2Na solution;

[0059] The third channel 7 is filled with silver nitrate solution.

[0060] Specifically include the following steps, refer to Figure 2 : In the specific test, the concentration of EDTA-2Na solution is 0.5mM EDTA-2Na, H2O / CH3OH (v / v=1 / 1); the concentration of silver nitrate is: 10mg / L AgNO3, H2O / CH3OH (v / v=1 / 1);

[0061] S1: At t=t0, the peristaltic pump 3 is started to pump water into the electrolytic cell 4 to extract the water-soluble components in the PM2.5 sample; the water-soluble components are divided into two equal parts, one of which is mixed with the EDTA-2Na introduced into the second channel 6, the metal ions in the aqueous solution component are complexed with EDTA-2Na to form an M-EDTA complex, and the organic acid in the water-soluble component is ionized by the electrospray ionization device 12 and enters the first mass spectrometer 8 for detection in the negative ion mode; the organic amine substances in the other equal part of the aqueous solution component are mixed with the AgNO3 introduced into the third channel 7, and after ionization by the electrospray ionization device 12, enter the second mass spectrometer 9 for detection in the positive ion mode;

[0062] After the mass spectrometry signal of the water-soluble component drops to the baseline level t=t1, the peristaltic pump 3 is started to pump methanol into the electrolytic cell 4 to extract the fat-soluble component, and the fat-soluble component is divided into two equal parts; one equal part of the fat-soluble component is mixed with EDTA-2Na of the second channel 6, and the fat-soluble organic acid is detected in the negative ion mode of the first mass spectrometer 8; the other equal part of the fat-soluble component is mixed with AgNO3 of the third channel 7, and the polycyclic aromatic hydrocarbons are complexed with AgNO3 to form Ag-PAHs complexes, which are detected by mass spectrum in the positive ion mode of the second mass spectrometer 9;

[0063] When the MS signal of the fat-soluble component drops to the baseline t=t2, the peristaltic pump 3 is started to pump the methanol EDTA-2Na aqueous solution into the electrolytic cell to extract the sparingly soluble metal substances, and the sparingly soluble metal components are divided into two equal parts, one of which is mixed with the EDTA-2Na in the second channel, and the M-EDTA complex formed by the complexation of the sparingly soluble metal ions and EDTA-2Na is ionized by the electrospray ionization device 12 and enters the first mass spectrometer 8 for detection in the negative ion mode. The other is mixed with the silver nitrate solution in the third channel 7, and is ionized by the electrospray ionization device 12 and enters the second mass spectrometer 9 for detection in the positive ion mode. No component information is obtained.

[0064] After the mass spectrometer signal of the sparingly soluble metal component drops to the baseline t=t3, EDTA-2Na aqueous solution is used as the electrolyte, voltage is applied using an electrochemical workstation, and the oxidizable metal components in PM2.5 are extracted by electro-oxidation method; the oxidizable metal component is divided into two equal parts, one of which is mixed with EDTA-2Na in the second channel, and the M-EDTA complex formed by the complexation of the oxidizable metal ions and EDTA-2Na is ionized by an electrospray ionization device 12 and detected in the first mass spectrometer 8 in the negative ion mode; the other equal part of the oxidizable metal component is mixed with the silver nitrate solution in the third channel 7, ionized by the electrospray ionization device 12 and entered into the second mass spectrometer 7 for detection in the positive ion mode, and no component information is obtained.

[0065] After the mass spectrometer signal of the oxidizable metal component drops to the baseline t=t4, the EDTA-2Na aqueous solution is still used as the electrolyte, the voltage is applied by the electrochemical workstation, and the reducible metal component is extracted by the electric reduction method; the reducible metal component is divided into two equal parts, one of which is mixed with the EDTA-2Na in the second channel, and the M-EDTA complex formed by the complexation of the reducible metal ions and EDTA-2Na is detected in the first mass spectrometer 8 under the negative ion mode via the electrospray ionization device 12; the other reducible metal component is mixed with the silver nitrate solution in the third channel 7, ionized by the electrospray ionization device 12 and entered into the second mass spectrometer 9 for detection under the positive ion mode, and no component information is obtained.

[0066] When the MS signal of the reducible metal component drops to the baseline at t=t5, the entire analysis procedure is completed.

[0067] The performance of the method was characterized using mixed samples of standard substances in different forms. The experiment showed that different species can be extracted sequentially without mutual interference. The ion chromatograms of each component in the mixed sample are shown in Table 1 and Figure 3 As shown, the recovery rate of each component is calculated to be 85.0%-110.0%.

[0068] Table 1 Recovery rates of various components in mixed samples detected by electrochemical-mass spectrometry analysis

[0069]

[0070] Under the premise that no conflict occurs, those skilled in the art may freely combine and superimpose the above-mentioned additional technical features.

[0071] The above-mentioned embodiments only express the preferred implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, various other corresponding changes and deformations can be made according to the technical solutions and concepts described above, and all these changes and deformations should fall within the scope of protection of the claims of the present invention.

Claims

1. An electrochemical-mass spectrometry analysis device for synchronously acquiring chemical information of inorganic and organic components in PM2.5, characterized in that: A first channel (5), a second channel (6) and a third channel (7) connected by a three-way joint; It also comprises a liquid storage bottle (1) and an electrolytic cell (4), wherein the liquid storage bottle (1) is connected to the electrolytic cell (4) via a six-way valve (2) and a peristaltic pump (3) in sequence, and the electrolytic cell (4) is connected to the first channel (5); The electrolytic cell (4) comprises a working electrode, a reference electrode and a counter electrode. The working electrode is provided with a conductive film (11), the conductive film (11) is connected to an electrochemical workstation via a Pt wire, a filter membrane (10) is attached to the conductive film (11), and PM2.5 particles are collected on the filter membrane (10); The second channel (6) and the third channel (7) are connected to the first mass spectrometer (8) and the second mass spectrometer (9) respectively, and an electrospray ionization device (12) is provided between the second channel (6) and the first mass spectrometer (8) and between the third channel (7) and the second mass spectrometer (9).

2. The electrochemical-mass spectrometry analysis device for synchronously acquiring chemical information of inorganic and organic components in PM2.5 according to claim 1, characterized in that: The electrospray ionization device (12) comprises a metal tube (13) capable of applying voltage, both ends of the metal tube (13) are connected to the capillary, and the metal tube (13) is exposed to the outside.

3. The electrochemical-mass spectrometry analysis method for synchronously acquiring chemical information of inorganic and organic components in PM2.5 according to claim 1, characterized in that: The second channel (6) and the third channel (7) both use capillaries of the same length.

4. The electrochemical-mass spectrometry analysis method for synchronously acquiring chemical information of inorganic and organic components in PM2.5 according to claim 1, characterized in that: The three-way joint is made of metal and is grounded.

5. The electrochemical-mass spectrometry analysis method for synchronously acquiring chemical information of inorganic and organic components in PM2.5 according to claim 1, characterized in that: The nebulization gas pressure of the two electrospray ionization devices (12) is the same.

6. The electrochemical-mass spectrometry analysis method for synchronously acquiring chemical information of inorganic and organic components in PM2.5 according to claim 1, characterized in that: The flow rates of the second channel (6) and the third channel (7) are the same.

7. An electrochemical-mass spectrometry analysis method for synchronously acquiring chemical information of inorganic and organic components in PM2.5, applied to the device as claimed in any one of claims 1 to 6, characterized in that: A filter membrane (10) collecting PM2.5 particles is attached to the conductive surface of a conductive membrane (11), and the solvent in the liquid storage bottle (1) is first transported to the electrolytic cell one by one through a peristaltic pump, and the water-soluble components, fat-soluble components and insoluble components in the PM2.5 particles are extracted and complexed in sequence, and the oxidizable and reducible metal compounds in the PM2.5 particles are extracted in sequence through electrochemical oxidation and reduction of an electrochemical workstation, and the substances added by the second channel (6) and the third channel (7) are combined with the extracted components for complexation; then, the components are ionized by an electrospray ionization device (12) and sent to a mass spectrometer for detection and analysis.

8. The electrochemical-mass spectrometry analysis method according to claim 7, characterized in that: The liquid storage bottles (1) are provided with three, respectively containing water, methanol and EDTA-2Na solution; The second channel (6) is fed with EDTA-2Na solution; The third channel (7) is filled with silver nitrate solution.

9. The electrochemical-mass spectrometry analysis method according to claim 8, characterized in that: The following steps are involved: S1: At t=t0, the peristaltic pump (3) is started to pump water into the electrolytic cell (4) to extract the water-soluble components in the PM2.5 sample; The water-soluble component is divided into two equal parts, wherein one equal part of the aqueous solution component is mixed with EDTA-2Na introduced into the second channel, the metal ions in the aqueous solution component are complexed with EDTA-2Na to form an M-EDTA complex which is ionized by an electrospray ionization device (12), and the organic acid in the water-soluble component is directly ionized by the electrospray ionization device (12) and enters the first mass spectrometer (8) for detection in the negative ion mode; the organic amine substances in the other equal part of the aqueous solution component are mixed with AgNO3 introduced into the third channel, ionized by the electrospray ionization device (12) and enter the second mass spectrometer (9) for detection in the positive ion mode; After the mass spectrometry signal of the water-soluble component drops to the baseline level t=t1, the peristaltic pump (3) is started to pump methanol into the electrolytic cell (4) to extract the fat-soluble component, and the fat-soluble component is divided into two equal parts; one equal part of the fat-soluble component is mixed with EDTA-2Na in the second channel, and the fat-soluble organic acid is detected in the negative ion mode of the first mass spectrometer (8); the other equal part of the fat-soluble component is mixed with AgNO3 in the third channel, and the polycyclic aromatic hydrocarbons are complexed with AgNO3 to form Ag-PAHs complexes, which are detected by mass spectrum in the positive ion mode of the second mass spectrometer (9); When the MS signal of the fat-soluble component drops to the baseline t=t2, the peristaltic pump (3) is started to pump the EDTA-2Na solution into the electrolytic cell to extract the sparingly soluble metal substances, and the sparingly soluble metal components are divided into two equal parts, wherein one equal part of the sparingly soluble metal components is mixed with the EDTA-2Na in the second channel, and the M-EDTA complex formed by the complexation of the sparingly soluble metal ions and EDTA-2Na is ionized by the electrospray ionization device (12) and enters the first mass spectrometer (8) for detection in the negative ion mode; the other equal part of the sparingly soluble metal components is mixed with the silver nitrate solution in the third channel (7), and is ionized by the electrospray ionization device (12) and enters the second mass spectrometer (9) for detection in the positive ion mode; After the mass spectrometry signal of the sparingly soluble metal component drops to the baseline t=t3, an EDTA-2Na solution is used as an electrolyte, a voltage is applied by an electrochemical workstation, and an electro-oxidation method is used to extract the oxidizable metal component in PM2.5; the oxidizable metal component is divided into two equal parts, one of which is mixed with the EDTA-2Na in the second channel, and the M-EDTA complex formed by the metal ion and the EDTA-2Na is ionized by an electrospray ionization device (12) and then detected in a first mass spectrometer (8) in a negative ion mode; the other equal part of the oxidizable metal component is mixed with the silver nitrate solution in the third channel (7), ionized by the electrospray ionization device (12) and then entered into a second mass spectrometer (7) in a positive ion mode for detection; After the mass spectrometry signal of the oxidizable metal component drops to the baseline t=t4, the EDTA-2Na solution is still used as the electrolyte, and the voltage is applied by the electrochemical workstation to extract the reducible metal component by the electric reduction method; the reducible metal component is divided into two equal parts, one of which is mixed with the EDTA-2Na in the second channel, and the M-EDTA complex formed by the metal ion and the EDTA-2Na is ionized by the electrospray ionization device (12) and then detected in the first mass spectrometer (8) in the negative ion mode; the other equal part of the metal component is mixed with the silver nitrate solution in the third channel (7), ionized by the electrospray ionization device (12) and then entered into the second mass spectrometer (9) in the positive ion mode for detection; When the MS signal of the reducible metal component drops to the baseline at t=t5, the entire analysis procedure is completed.

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