High-throughput and high-sensitivity qualitative and quantitative analysis method for organic components in solid samples

Abstract

The present invention discloses a high-throughput and high-sensitivity qualitative and quantitative analysis method for organic components of solid samples. The present invention adopts a non-targeted method of direct thermal desorption technology of the injection port of a gas chromatograph, which does not require pre-treatment, has little blank interference, is simple to operate, has good parallelism, and greatly shortens the time and manpower required for the sample extraction process; the present invention combines a gas chromatography-time-of-flight mass spectrometer, and only requires about 1 microgram of sample to complete sample detection, greatly reducing the sample loss rate; the detection species has a high flux and a wide concentration range, breaking through the limitations of existing scientific cognition, and can systematically identify and quantify more than 1,500 organic species, including aromatic oxygen-containing substances, aromatic nitrogen-containing substances, chain alkane substances and benzene series, etc., to achieve all potential organic species. Qualitative and quantitative non-targeted analysis, thereby improving the detection ability of samples.

Description

Technical Field

[0001] The invention relates to a detection technology for organic components in solid samples, and in particular to a high-throughput and high-sensitivity qualitative and quantitative comprehensive analysis method. Background Art

[0002] The analysis of organic components in solid samples can reveal the composition, structure and properties of substances, and is the research basis in the fields of chemistry, chemical engineering, agricultural production, petroleum industry, environmental science, etc. However, organic components are of various types and complex structures. At present, the detection of complex organic components in solid samples mainly uses a variety of physical and chemical separation methods, such as commonly used solid-liquid extraction, ion exchange, chromatography separation, etc. to separate and purify organic components from solid samples, and use infrared spectroscopy, mass spectrometry, and nuclear magnetic resonance detection. Among them, chromatography-mass spectrometry is widely used due to its high sensitivity and selectivity and qualitative and quantitative capabilities. However, the traditional analysis method of organic components in solid samples still has problems such as complex operation, serious matrix interference, and huge sample consumption. Due to the limitation of standard products, only a small amount of organic components can be qualitatively and quantitatively analyzed, which cannot meet the requirements of high-throughput identification and quantification of new organic components. Therefore, there is a lack of suitable organic component system analysis technology for solid samples with small sample volume and low organic component concentration. Summary of the invention

[0003] In view of the problems of complex pretreatment operation, serious blank interference, huge sample consumption, low detection sensitivity and throughput in traditional solid sample organic components, the present invention proposes a high-throughput and high-sensitivity qualitative and quantitative organic component analysis method, which does not require sample pretreatment and uses direct thermal desorption technology at the injection port to extract potential organic matter in the sample. Combined with gas chromatography-time-of-flight mass spectrometry, it can obtain standardized fragment mass information of more than 1,500 organic species with high throughput, thereby realizing potential full qualitative and quantitative, i.e. non-targeted detection.

[0004] Gas chromatography-time of flight mass spectrometry includes a gas chromatograph and a time of flight mass spectrometer connected in series.

[0005] The high-throughput and high-sensitivity qualitative and quantitative organic component analysis method of the present invention comprises the following steps:

[0006] 1) Before testing, quality control samples with known organic components were used to indicate the stability of the gas chromatography-time-of-flight mass spectrometer between different batches of testing;

[0007] 2) freeze-drying the solid sample for later use;

[0008] 3) adding the solid sample to be tested into a clean injection vial, the mass of the sample to be tested being the same as the mass of the quality control sample used to indicate the gas chromatograph and the time-of-flight mass spectrometer in step 1), adding an internal standard substance, and transferring the prepared injection vial to the injection port of the gas chromatograph-time-of-flight mass spectrometer;

[0009] 4) The initial temperature of the injection port of the gas chromatography-time-of-flight mass spectrometer is set higher than room temperature, the injection port is heated and pressurized, the temperature of the injection port of the gas chromatography-time-of-flight mass spectrometer is gradually increased from low temperature to high temperature in stages, and there is a residence time at each temperature, and the solid sample to be tested is thermally desorbed into a gaseous state during the heating process; thermal desorption is performed in stages to shorten the residence time of the solid sample to be tested in the injection port; during the thermal desorption process, a purge gas flow is blown to the injection port to the split outlet to prevent the injection port from being contaminated after the thermal desorption of the sample is completed; and in the initial stage of heating, the pressurization mode of the injection port is maintained in a pulsed non-split mode to reduce the matrix effect, improve the chromatographic peak shape and reduce peak broadening;

[0010] 5) The sample to be tested that is thermally desorbed into a gaseous state flows into a gas chromatography column of a gas chromatograph, and the gas chromatography column is heated in stages from low temperature to high temperature to ensure that the gaseous sample to be tested flows out of the gas chromatography column in sequence according to volatility and binding ability with the gas chromatography column, and a gas chromatographic peak is collected, and the gas chromatographic peak is a peak spectrum of chromatographic retention time, and the chromatographic retention time is the retention time of the organic matter on the gas chromatography column; the gas chromatograph collects the gas chromatographic peak of the low-boiling point easily degradable organic component at low temperature, and collects the gas chromatographic peak of the high-boiling point organic component at high temperature, thereby realizing the simultaneous collection of the gas chromatographic peaks of the low-boiling point easily degradable organic component and the high-boiling point organic component;

[0011] 6) The gaseous sample to be tested flows into the time-of-flight mass spectrometer through the gas chromatograph; the gaseous sample is ionized by using an electron bombardment ion source and an electron capture negative ionization source respectively to obtain a mass spectrum peak spectrum; the mass spectrum peak spectrum is the accurate mass number information spectrum of the fragment ions generated by the organic matter under the electron bombardment ion source and the accurate mass number information spectrum of the molecular ions generated under the electron capture negative ionization source; the accurate mass number information spectrum of the fragment ions and the accurate mass number information spectrum of the molecular ions are called the accurate mass number information spectrum of the ions;

[0012] 7) Get the list of organic matter information:

[0013] a) classifying the ion accurate mass information spectra with similar chromatographic peak curves and similar retention times as the same organic signal, and using the three characteristics of ion accurate mass, chromatographic retention time and absolute gas chromatographic peak area to represent each organic signal;

[0014] b) performing peak filtering, peak alignment, peak normalization, peak standardization and statistical filtering on each organic signal in a), removing false positive and false negative organic signals, so as to obtain an organic information list including ion accurate mass number, chromatographic retention time and standardized gas chromatographic peak area;

[0015] 8) Qualitative identification of unknown organic matter: Match the organic matter information list generated by the electron bombardment ion source and the electron capture negative ionization source by chromatographic retention time, determine the molecular composition and molecular formula of the unknown organic matter by the accurate mass number of the molecular ion, and determine the fragment structure and molecular structure of the organic matter by the accurate mass number of the fragment ion; synthesize standard chemicals according to the obtained structure, repeat the above steps 2) to 7) for confirmation, so as to obtain the same information list;

[0016] 9) Quantification of organic matter: A series of reference solutions of different concentrations are prepared according to the synthesized standard chemicals, and internal standard substances are added to determine the working curve, and the concentration of the organic species to be tested in the sample is quantified; thus achieving non-targeted qualitative and quantitative analysis of all potential organic matter.

[0017] Wherein, in step 1), a quality control sample with known organic components is used to indicate stability: the quality control sample with known organic components is operated according to steps 2) to 7) to obtain an organic matter information list of the quality control sample with known organic components; the coefficient of variation of the ratio of the absolute peak area of ​​the known organic matter in the list to the absolute peak area of ​​the internal standard substance must be less than a coefficient threshold, and the coefficient threshold is 10% to 30%. If it is higher than the coefficient threshold, the gas chromatography-time-of-flight mass spectrometer must be cleaned and step 1) must be repeated again.

[0018] In step 3), the internal standard substance is a deuterated or carbon 13-substituted standard substance. The internal standard substance is extracted by a sample injection needle using a sandwich sampling method and gently injected into the sample to be tested, ensuring that all the residual internal standard substance in the sample injection needle is blown out.

[0019] In step 4), the initial temperature of the injection port is 5 to 10°C higher than the room temperature. The temperature gradient of the staged heating from low temperature to high temperature is 50°C to 100°C; the residence time at each temperature is 0 to 5 minutes; the temperature range from low temperature to high temperature is 40°C to 310°C. The pressure on the injection port is 0 to 50 psi. Thermal desorption is carried out in stages to ensure that the chromatographic peak height ranges from 1000 to 1000000 to shorten the residence time of the solid sample to be tested in the injection port. A liner is placed in the injection port, and the liner is used to fix the position of the injection vial in the injection port so that the injection vial is at the same scale in the injection port.

[0020] In step 5), the gas chromatography column is heated from low temperature to high temperature in stages, with a temperature gradient of 50°C to 100°C; the residence time at each temperature is 0 to 15 minutes; and the temperature range from low temperature to high temperature is 40°C to 310°C.

[0021] In step 6), the internal standard substances in the electron impact ion source analysis include internal standard substances of polycyclic aromatic hydrocarbons and internal standard substances of alkanes; the internal standard substances in the electron capture negative ionization source analysis include internal standard substances of nitro polycyclic aromatic hydrocarbons and internal standard substances of oxidized polycyclic aromatic hydrocarbons.

[0022] In step 7) a), similar chromatographic peak curves refer to that the difference in curvature of the slope of half of the chromatographic peak is less than the curvature difference threshold, and the difference threshold is 5 to 15 degrees; similar retention times refer to that the difference in retention time at the chromatographic peak is less than the time difference threshold, and the time difference threshold is 0.02 to 0.1 minutes.

[0023] Advantages of the present invention:

[0024] The present invention adopts a non-targeted method of direct thermal desorption technology at the injection port of a gas chromatograph, which does not require pretreatment, has little blank interference, is simple to operate, and has good parallelism, greatly shortening the time and manpower required for the sample extraction process; the present invention only requires about 1 microgram of sample to complete sample detection, greatly reducing the sample loss rate; the detection species flux is high and the concentration range is wide, breaking through the limitations of existing scientific cognition, and can systematically identify and quantify more than 1,500 organic species, including aromatic oxygen-containing substances, aromatic nitrogen-containing substances, chain alkanes and benzene series, etc., to achieve all potential organic species. Qualitative and quantitative non-target analysis, thereby improving the detection capability of the sample. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The present invention is a flowchart of the high-throughput and high-sensitivity qualitative and quantitative organic component analysis method. DETAILED DESCRIPTION

[0026] The present invention will be further described below through specific embodiments in conjunction with the accompanying drawings.

[0027] like Figure 1 As shown, the high-throughput and high-sensitivity qualitative and quantitative organic component analysis method of this embodiment comprises the following steps:

[0028] 1) Before the test, a 1 microgram quality control sample of known organic components is used to evaluate the gas chromatography-time-of-flight mass spectrometer, and steps 2) to 7) are performed to obtain a list of organic information of the quality control sample of known organic components; the coefficient of variation of the ratio of the absolute peak area of ​​the known organic matter to the absolute peak area of ​​the internal standard substance in the list must be less than 30%. If it is higher than 30%, the gas chromatography-time-of-flight mass spectrometer must be cleaned and evaluated again until the coefficient of variation of the ratio of the absolute peak area of ​​the known organic matter to the absolute peak area of ​​the internal standard substance is less than 20%, so as to ensure the stability of the detection between different batches of the same sample;

[0029] 2) Dry the individual quartz film exposed to fine particles and take the solid sample to be tested for later use;

[0030] 3) Use a clean gun to take out a 3mm diameter (1 microgram) sample and slowly push it into the bottom of the vial to ensure that there is no obvious sample residue on the inner wall of the vial; clean the injection needle with 3 injections of acetone and 3 injections of n-hexane in sequence, add 1 microgram of the solid sample to be tested into a clean injection vial, add 1 microliter of deuterated or carbon 13 substituted standard as the internal standard substance (internal standard), use the injection needle to use the sandwich sampling method to extract the internal standard and gently inject it into the sample, use tweezers to take out the injection vial and push it into the bottom of the liner of the injection port, quickly close the injection port, open the injection port pressure and wait for the pressure to rise and start the sample; ensure that all the residual standard samples in the injection needle are blown out, and then transfer the prepared injection vial to the injection port of the gas chromatography-time of flight mass spectrometer; accurately record and control the manual injection process to ensure the continuity and parallelism of the sampling process; the internal standard includes the internal standard of polycyclic aromatic hydrocarbons (d 10 -pyrene, d 10 -Anthracene, d 12 -Benzo[a]anthracene, d 10 -fluorene, d4-1,4-dichlorobenzene, d8-naphthalene, d 10 -phenanthrene) and paraffin internal standards (d 50 -n-Tetracosane, d 62 -n-hexadecane, d 34 -n-heptadecane), internal standard of nitro polycyclic aromatic hydrocarbons (d9-nitroanthracene, d9-nitropyrene, d9-nitrofluorene)

[0031] and internal standards of oxidized PAHs (2-fluorofluorene, 1-chloroanthraquinone);

[0032] 4) The initial temperature of the injection port of the gas chromatography-time-of-flight mass spectrometer is set to be 5 to 10°C higher than the room temperature, the injection port is heated and pressurized, and the temperature of the injection port of the gas chromatography-time-of-flight mass spectrometer is gradually increased from low temperature to high temperature in stages, the initial temperature of the injection port is 50°C, and it is maintained for 0.5 min; the final temperature is set to 300°C to collect high-boiling point organic components; in order to collect low-boiling point easily degradable organic components and high-boiling point organic components at the same time, thermal desorption is performed in stages to ensure that the chromatographic peak height ranges from 1000 to 1000000, and the heating rate is 500℃ / min, intermediate temperature dwell time 0min, injection port final temperature 300℃ holding time 5min, injection port thermal desorption total time of 6min, to prevent injection port impurities from contaminating the gas chromatography-time-of-flight mass spectrometer after injection port sample thermal desorption, start injection port 50mL / min injection port purge gas flow to the split outlet at 6min; to reduce matrix effect, improve chromatographic peak shape and reduce peak broadening, maintain 50psi pulse non-split mode from 0 to 2min; during the heating process, the solid sample to be tested is thermally desorbed into gaseous state;

[0033] 5) Using high-purity helium as carrier gas, when the gaseous sample to be tested flows into the gas chromatography column, the gas chromatography column is gradually heated from low temperature to high temperature in stages to ensure that the gaseous sample to be tested flows out of the gas chromatography column in sequence according to volatility and binding ability with the gas chromatography column, and the gas chromatography peak is collected; the gas chromatography peak is the peak spectrum of the elution at the retention time of the chromatographic column; when two gas chromatography columns are connected in series, the flow rates of the first gas chromatography column and the second gas chromatography column are constant at 1.0 and 1.2 mL / min; in order to make the organic components gather at the head of the chromatographic column during the thermal desorption process of the injection port, The initial temperature of the gas chromatography column is determined to be slightly lower than the initial temperature of the injection port, which is 40°C and maintained for 2 minutes, and then increased to 300°C at 8°C / min and maintained for 13 minutes; the post-purge temperature of the gas chromatography column is 310°C, the holding time is 5 minutes, the backflush system pressure is 48 psi, and the entire program running time is 46.5 minutes; the gas chromatograph collects the gas chromatographic peaks of the low-boiling-point easily degradable organic components at low temperature, and collects the gas chromatographic peaks of the high-boiling-point organic components at high temperature, thereby realizing the simultaneous collection of the gas chromatographic peaks of the low-boiling-point easily degradable organic components and the high-boiling-point organic components;

[0034] 6) The gaseous sample to be tested flows into the time-of-flight mass spectrometer through the gas chromatograph; the transmission line temperature is 280°C;

[0035] The gaseous sample was ionized by an electron bombardment ion source, which was maintained at 250°C and a filament voltage of 70 eV. The mass spectrum m / z mass range was 70-500, and the acquisition rate was 5 Hz. The samples were collected in two modes, namely, bar graph and profile graph, to obtain the accurate mass number information spectrum of the fragment ions produced by the organic matter under the electron bombardment ion source. The internal standards in the electron bombardment ion source analysis included polycyclic aromatic hydrocarbons and chain alkanes.

[0036] An electron capture negative ionization source is used to ionize the gaseous sample. The electron capture negative ionization source is maintained at 150° C. Methane is used as the reaction gas (40%). The mass spectrum m / z mass range is 70-500. The acquisition rate is 5 Hz. The spectrum is acquired in two modes: a bar graph and a contour graph. The accurate mass number information spectrum of the molecular ion is obtained. The accurate mass number information of the fragment ion and the accurate mass number information of the molecular ion are collectively referred to as the accurate mass number information of the ion. The internal standards in the electron capture negative ionization source analysis include the internal standards of nitro polycyclic aromatic hydrocarbons and the internal standards of oxidized polycyclic aromatic hydrocarbons.

[0037] 7) Get the list of organic matter information:

[0038] a) The difference in the slope curvature of one-half of the chromatographic peaks is less than 10 degrees, which is considered to be similar. The difference in retention time at the chromatographic peak is less than 0.05 minutes, which is considered to be similar retention time elution. The ion accurate mass number information spectrum of the mass spectrum peak spectrum corresponding to the similar chromatographic peak curve and the similar retention time elution is summarized as the same organic signal. Each organic signal is represented by the three characteristics of ion accurate mass number, chromatographic retention time and absolute chromatographic peak area;

[0039] b) For each organic signal in a), perform:

[0040] Peak filtering: further screen out the chromatographic peaks of compounds with chromatographic peak height greater than 5000, and discard chromatographic signals with too low abundance;

[0041] Peak alignment: After superimposing the total ion chromatograms of different samples, the retention time drift window is controlled within 0.1 minutes, and the accurate mass drift window is controlled within 15ppm+2.0mDa;

[0042] Peak normalization, peak standardization and statistical filtering: The normalization method is to divide the peak area of ​​each organic compound by the total organic compound peak area to correct the influence of excessive differences in absolute concentration of the same organic compound between different samples; the standardization method is used to eliminate the influence of excessive differences in concentration levels between different organic compounds in the same sample to prevent changes in low-content organic compounds from being masked by changes in high-content organic compounds;

[0043] False positive and false negative organic signals are removed to obtain an organic information list including ion accurate mass, chromatographic retention time and normalized gas chromatographic peak area;

[0044] After the above signal filtering, the parallelism of organic matter in the quality control sample should be tested. On this basis,

[0045] Taking 50% of the actual sample as the screening standard for organic matter, extract the organic matter that is stably present in the actual sample; 8) Qualitative identification of unknown organic matter: List the organic matter information generated by the electron bombardment ion source and the electron capture negative ionization source through

[0046] Through chromatographic retention time matching, the molecular composition and molecular formula of unknown new organic compounds are determined using the accurate mass information of molecular ions, and the fragment structure and molecular structure of organic compounds are determined using the accurate mass information of fragment ions. Specifically, it includes:

[0047] The identification of electron ionized species includes: matching the mass spectrum peak with the standard reference library (11.L) developed by the National Institute of Standards and Technology (NIST) for mass spectrometry data analysis; the deviation between the accurate mass number of the reference molecular ion or fragment ion and the mass number detected by the present invention is within 25ppm, such as the fragment ion of hopane is [C 14 H 23 ] + (accurate mass 191.1794, same below); the fragment ion of chain alkane is [C5H 10 ] + (70.0774), [C5H 11 ] + (71.0852),

[0048] [C7H 13 ] + (97.1007); Alkanoic acid is [C3H6O2] + (74.0359), [C4H7O2] + (87.0437); dicarboxylic acid is [C4H5O2] + (85.0281); methylsiloxane is [SiO(CH3)2] + (73.0468); The key functional groups are determined by the exact mass of the lost fragments, such as the exact mass of the lost CH3 fragments in the mass spectrum peak of alkyl polycyclic aromatic hydrocarbons.

[0049] 15.0235; the missing CO in the mass spectrum peak of oxidized PAHs is 27.9949, and C2O2 is 55.9898; the CH2N in the mass spectrum peak of nitrogen-containing PAHs is 28.0187; the CHO in the mass spectrum peak of oxygen-containing PAHs is 29.0027; the standardized retention time index of unknown compounds is obtained by the retention time of normal alkanes, and the position of isomers can be determined by matching the retention time index in the literature; finally, commercial or laboratory synthetic standards are purchased and analyzed by chromatography-mass spectrometry using the same experimental method to determine the organic components to be identified;

[0050] The identification of electron capture negative ionization species includes: the ion fragments with a mass number difference of 1.0034, 2.0068 and a peak area within 30% of the screened accurate ion fragment retention time of 0.02min are determined as isotope peaks; the same elution mass spectrum peak pair with the same retention time is attributed to the same compound, and the elemental composition is confirmed according to its isotope peak abundance ratio; according to the classical mass difference (14.0157 n That is (CH2) n Determine it as a homologue; compare the retention time with the electron ionization source under the same chromatographic conditions to determine the functional group structure or molecular isomers of the substance; finally, purchase commercial or laboratory synthesized standards and use the same experimental method to perform chromatographic mass spectrometry analysis to determine the organic components to be identified;

[0051] Synthesize standard chemicals according to the obtained structure, and repeat the above steps 2) to 7) for confirmation, thereby obtaining the same information list;

[0052] 9) Organic Quantification: Standard chemicals prepared according to the synthesis were used to construct a standard curve based on 10, 50, 100, 250, 50, 1000, 2000 and 5000 ng / mL standards, and the concentration of the organic species to be tested in the samples was quantified.

[0053] Finally, it should be noted that the purpose of publishing the embodiments is to help further understand the present invention, but those skilled in the art can understand that various substitutions and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the present invention should not be limited to the contents disclosed in the embodiments, and the scope of protection claimed by the present invention shall be subject to the scope defined in the claims.

Claims

1. A high-throughput and high-sensitivity qualitative and quantitative organic component analysis method, characterized in that: The analytical method comprises the following steps: 1) Before testing, quality control samples with known organic components were used to indicate the stability of the gas chromatography-time-of-flight mass spectrometer between different batches of testing; 2) freeze-drying the solid sample for later use; 3) adding the solid sample to be tested into a clean injection vial, the mass of the sample to be tested being the same as the mass of the quality control sample used to indicate the gas chromatograph and the time-of-flight mass spectrometer in step 1), adding an internal standard substance, and transferring the prepared injection vial to the injection port of the gas chromatograph-time-of-flight mass spectrometer; 4) The initial temperature of the injection port of the gas chromatography-time-of-flight mass spectrometer is set higher than room temperature, and the injection port is heated and pressurized. The temperature of the injection port of the gas chromatography-time-of-flight mass spectrometer is gradually increased from low temperature to high temperature in stages, and there is a residence time at each temperature. During the heating process, the solid sample to be tested is thermally desorbed into a gaseous state; thermal desorption is performed in stages to shorten the residence time of the solid sample to be tested in the injection port; during the thermal desorption process, a purge gas flow is blown to the split outlet from the injection port to prevent the injection port from being contaminated after the thermal desorption of the sample is completed; and in the initial stage of heating, the pressurization mode of the injection port is maintained in a pulsed non-split mode to reduce the matrix effect, improve the chromatographic peak shape and reduce the peak broadening; 5) The sample to be tested that is thermally desorbed into a gas state flows into a gas chromatographic column of a gas chromatograph, and the gas chromatographic column is heated in stages from low temperature to high temperature to ensure that the gaseous sample to be tested flows out of the gas chromatographic column in sequence according to volatility and binding ability with the gas chromatographic column, and a gas chromatographic peak is collected, and the gas chromatographic peak is a peak spectrum of chromatographic retention time, and the chromatographic retention time is the retention time of the organic matter on the gas chromatographic column; the gas chromatographic instrument collects the gas chromatographic peak of the low-boiling point easily degradable organic component at low temperature, and collects the gas chromatographic peak of the high-boiling point organic component at high temperature, thereby realizing the simultaneous collection of the gas chromatographic peaks of the low-boiling point easily degradable organic component and the high-boiling point organic component; 6) The gaseous sample to be tested flows into the time-of-flight mass spectrometer through the gas chromatograph; the gaseous sample is ionized by using an electron bombardment ion source and an electron capture negative ionization source respectively to obtain a mass spectrum peak spectrum; the mass spectrum peak spectrum is the accurate mass number information spectrum of the fragment ions generated by the organic matter under the electron bombardment ion source and the accurate mass number information spectrum of the molecular ions generated under the electron capture negative ionization source; the accurate mass number information spectrum of the fragment ions and the accurate mass number information spectrum of the molecular ions are called the accurate mass number information spectrum of the ions; 7) Get the list of organic matter information: a) classifying the ion accurate mass information spectra with similar chromatographic peak curves and similar retention times as the same organic signal, and using the three characteristics of ion accurate mass, chromatographic retention time and absolute gas chromatographic peak area to represent each organic signal; b) performing peak filtering, peak alignment, peak normalization, peak standardization and statistical filtering on each organic signal in a); False positive and false negative organic signals are removed to obtain an organic information list including ion accurate mass, chromatographic retention time and normalized gas chromatographic peak area; 8) Qualitative identification of unknown organic matter: Match the organic matter information list generated by the electron bombardment ion source and the electron capture negative ionization source by chromatographic retention time, determine the molecular composition and molecular formula of the unknown organic matter by the accurate mass number of the molecular ion, and determine the fragment structure and molecular structure of the organic matter by the accurate mass number of the fragment ion; synthesize standard chemicals according to the obtained structure, repeat the above steps 2) to 7) for confirmation, so as to obtain the same information list; 9) Quantification of organic matter: A series of reference solutions of different concentrations are prepared according to the synthesized standard chemicals, and internal standard substances are added to determine the working curve, and the concentration of the organic species to be tested in the sample is quantified; thus achieving non-targeted qualitative and quantitative analysis of all potential organic matter.

2. The analysis method according to claim 1, characterized in that In step 1), a quality control sample with known organic components is used to indicate stability: the quality control sample with known organic components is operated according to steps 2) to 7) to obtain an organic matter information list of the quality control sample with known organic components; the coefficient of variation of the ratio of the absolute peak area of ​​the known organic matter in the list to the absolute peak area of ​​the internal standard substance must be less than the coefficient threshold. If it is higher than the coefficient threshold, the gas chromatography-time-of-flight mass spectrometer must be cleaned and step 1) must be repeated again until the coefficient of variation of the ratio of the absolute peak area of ​​the known organic matter to the absolute peak area of ​​the internal standard substance is less than the coefficient threshold.

3. The analysis method according to claim 2, characterized in that The coefficient threshold is 10% to 30%.

4. The analysis method according to claim 1, characterized in that In step 3), the internal standard substance is a deuterated or carbon 13-substituted standard substance.

5. The analysis method according to claim 1, characterized in that In step 3), the internal standard substance is extracted using a sampling needle using a sandwich sampling method and injected into the sample to be tested, ensuring that all the residual internal standard substance in the sampling needle is blown out.

6. The analysis method according to claim 1, characterized in that In step 4), the initial temperature of the injection port is 5 to 10° C. higher than room temperature.

7. The analysis method according to claim 1, characterized in that In step 4), the temperature gradient of the gas chromatography column from low temperature to high temperature is 50°C to 100°C; the residence time at each temperature is 0 to 5 minutes; the temperature range from low temperature to high temperature is 40°C to 310°C.

8. The analysis method according to claim 1, characterized in that In step 4), a liner is placed in the injection port, and the liner is used to place the injection vials at the same scale in the injection port, thereby fixing the positions of the injection vials in the injection port.

9. The analysis method according to claim 1, characterized in that In step 6), the internal standard substances in the electron impact ion source analysis include internal standard substances of polycyclic aromatic hydrocarbons and internal standard substances of alkanes; the internal standard substances in the electron capture negative ionization source analysis include internal standard substances of nitro polycyclic aromatic hydrocarbons and internal standard substances of oxidized polycyclic aromatic hydrocarbons.

10. The analysis method according to claim 1, characterized in that In step 7) a), similar chromatographic peak curves refer to that the difference in curvature of the slope of half of the chromatographic peak is less than the curvature difference threshold, and the difference threshold is 5 to 15 degrees; similar retention times refer to that the difference in retention time at the chromatographic peak is less than the time difference threshold, and the time difference threshold is 0.02 to 0.1 minutes.

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