WO2019200946A1 - Gc-q-orbitrap-based electronic identification database of pesticide compounds in edible agricultural products and detection method - Google Patents

Abstract

A GC-Q-Orbitrap-based electronic identification database of pesticide compounds in edible agricultural products and a detection method; the electronic identification database comprises the assembling of electronic identity card information of a plurality of pesticide compounds, and sorting according to the retention times in the electronic identity card, wherein the electronic identity card comprises pesticide compound information, retention time, a mass spectrograph, fragment ion information and a smart matching value; the detection method comprises a sample pretreatment step, the setting of GC-Q-Orbitrap operation conditions, and a pesticide residue screening process in the sample, wherein the setting of GC-Q-Orbitrap operation conditions comprises setting a suitable chromatographic condition and mass spectrometry condition and, in a pesticide screening process, first utilizing the retention time to search for a pesticide compound in the electronic identification database, and extracting corresponding electronic identity card information if matching is successful, then comparing a smart matching value, and recording and displaying a result if the smart matching value is less than a threshold, and screening is thus finished.

Description

Electronic identity database and detection method of pesticide compounds in edible agricultural products based on GC-Q-Orbitrap Technical field

The invention designs an electronic identity database and a detection method for pesticide compounds in edible agricultural products based on GC-Q-Orbitrap, and the invention can realize non-target, multi-index and rapid screening for more than 600 pesticide residues in various edible agricultural products.

Background technique

As early as 1976, the World Health Organization (WHO), FAO (FAO) and the United Nations Environment Programme (UNEP) jointly established the Global Environment Monitoring System/Food Project (GEMS/Food) to grasp the food contamination situation of member countries. To understand the intake of food contaminants, protect human health and promote trade development. Now, all countries in the world have promoted food safety to a strategic position in national security. Pesticide residue limits are one of the food safety standards and an entry barrier to international trade. At the same time, the requirements for pesticide residues show more and more varieties, and the development trend of more and more strict limits, that is, the threshold for pesticide residue set by international trade is getting higher and higher. For example, the European Union, Japan, and the United States have formulated 169,068 (481 pesticides), 44,340 (765 pesticides), and 1,305 (395 pesticides) pesticide residue limits. In 2016, China released 4,140 MRLs for 433 pesticides. standard. At present, the standard limit commonly used in the world is 10μg/kg. Therefore, both food safety and international trade call for high-throughput rapid pesticide residue detection technology, which undoubtedly provides opportunities and challenges for pesticide residue analysis workers. Among the many pesticide residue analysis technologies available today, chromatographic mass spectrometry is the best analytical tool for high-throughput multi-residue rapid detection.

At present, the analysis of pesticide residues is mainly based on gas chromatography, liquid chromatography, gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry. These detection techniques first need to be qualitatively compared to pesticide standards. For example, the detection of 100 pesticides requires the preparation of the corresponding 100 pesticide standard controls, and these 100 pesticides will be missed. In the actual work of pesticide residue laboratories, most laboratories do not stock hundreds of pesticide standards. The reason is that pesticide standards are not only expensive, but also valid for only 2 or 3 years, requiring repeated investment. There are only a few dozen standard pesticide standards in the laboratory, and the number of pesticides that are routinely monitored is limited to these dozens, which leads to food safety monitoring loopholes.

Summary of the invention

The invention solves the problem that the rapid detection of multiple pesticides at the same time can not be realized in the current pesticide residue screening technology method, and develops an electronic identity database and detection method of pesticide compounds based on GC-Q-Orbitrap for edible agricultural products, which realizes that no need Standard product control can quickly screen and detect more than 600 pesticide residues in agricultural products, which meets the urgent need for rapid detection of high-throughput pesticide residues in agricultural products.

The invention adopts the following technical solutions:

An electronic identity database of pesticide compounds in edible agricultural products based on GC-Q-Orbitrap, comprising a plurality of pesticide compound electronic identification cards, including pesticide compound information, retention time, mass spectrum, and fragment ion information, characteristics thereof Lie in:

The pesticide compound information includes a compound name, a compound molecular formula;

Preparing a sample of the pesticide compound, and obtaining a chromatogram of the pesticide compound under specified chromatographic mass spectrometry conditions in a Full MS mode by a GC-Q-Orbitrap apparatus, wherein the time of the peak in the chromatogram is the retention time;

The mass spectrum is a first-level full scan obtained by the GC-Q-Orbitrap instrument at the retention time;

The fragment ions are determined by selection in the mass spectrum, and the fragment ions include one base peak ion and a plurality of confirming ions, and the base peak ions are fragment ions having high signal intensity and large mass, the base peak The ion does not select the ion of the isotope peak;

The fragment ion information includes an ion abundance ratio and a theoretical accurate mass number;

The ion abundance ratio is a signal intensity ratio of the fragment ion to the base peak ion;

The database is sorted by retention time in the electronic ID card.

Further, the electronic identity database further includes an intelligent matching model, and the matching model adds an intelligent matching value P _{m to} the electronic identity card, and the computing model is:

W _b + W _q =1;

Where M _b is the theoretical exact mass of the base peak ion, M _i is the exact mass of the ith confirmed ion, W _i is the weight, and I _i is the ion abundance ratio of the ith confirmed ion, confirming the order of the ions The ion abundance ratio is from large to small; W _b is the weight of the base peak ion, W _q is the comprehensive weight of the confirmed ion, and n is the number of fragment ions.

Further, the W _b , W _q can be adjusted according to the change of the smart matching model, and generally takes the value W _b = W _q = 0.5.

Further, the selection of the fragment ions depends on the ion abundance and the ion mass number, wherein the ion abundance is the signal intensity of the ions in the mass spectrum, and the number of the fragment ions is five, and the principle of the fragment ion selection is :

If ΔI>10%, the maximum value in I _i , I _j is selected, otherwise the maximum value in M _i , M _j is selected;

Where: I _i , I _j are the ion abundance ratios of the two closest fragment ions, ΔI=|I _i -I _j |, M _i , M _j are the exact masses of the two closest fragment ions, The arrangement of the ion fragments is in accordance with the ion abundance ratio from large to small.

Further, the method for determining the theoretical accurate mass of the fragment ions is:

1) clarify the composition of the fragment ion element according to the molecular formula of the compound;

2) According to the mass number M of the fragment ions in the mass spectrum, a list of possible fragment ion element compositions is obtained by calculation;

Where: M _i is the exact mass of the i-th fragment ion element, n is the number of elements of the fragment ion, and y _i is the number of elements corresponding to the i-th fragment ion.

3) Select a reasonable fragment ion element composition from the list of fragment ion element composition by the molecular structure cracking mechanism, and calculate its theoretical exact mass M'.

M'=M ₁ y' ₁ +M ₂ y' ₂ +...+M _n y' _n

Wherein: M ₁ , M _{2 ,} ..., M _n is the exact mass of the fragment ion element, and y' ₁ , y' ₂ , ... y' _n are the number of corresponding elements of the preferred fragment ion element composition.

Further, when two or more chromatographic peaks appear in the chromatogram, a retention index of the pesticide compound is calculated, and a retention time of the pesticide compound is determined by the retention index being close to a standard retention index of the pesticide compound;

The calculation method of the retention index R _I is:

The retention time t _R is the correction, and the z-z + 1, respectively pesticide compound (x) of the effluent before and after the n-paraffins of the number of carbon atoms, the _{t R (z) <t R} (x) < t _R (z+1), the number z of carbon atoms contained in normal paraffins in a general pesticide compound is greater than 4.

Further, the chromatographic mass spectrometry conditions are:

Chromatographic conditions: GC column is TG-5SILMS, 30m × 0.25mm (id) × 0.25μm special column for mass spectrometry; temperature programming process: 40 ° C for 1 min, then programmed to 30 ° C / min to 130 ° C, then 5 ° C /min warmed to 250 ° C, and then heated to 300 ° C at 10 ° C / min, held for 5 min; carrier gas: helium, purity ≥ 99.999%, flow rate 1.2mL / min; inlet type: PTV; injection volume: 1μL ; injection method: temperature programmed injection, no split time 1.5min;

Mass spectrometry conditions: EI source voltage: 70 eV; ion source temperature: 230 ° C; transmission line temperature: 280 ° C; solvent delay: 4 min. Scanning mode: Full MS; mass scanning range 50-600 m/z, resolution 60,000 FHWM (200 m/z); epoxy heptachlor was used to adjust retention time.

A method for detecting pesticide compounds in edible agricultural products based on GC-Q-Orbitrap, comprising:

1) The sample to be tested is extracted by homogenization of acetic acid acetonitrile, dehydrated, centrifuged, concentrated, and then purified by Carbon/NH2 column, and the residual pesticide is eluted by acetonitrile + toluene, and concentrated and filtered to prepare a sample solution to be tested;

2) Obtain a chromatogram and a mass spectrum of the sample solution under the specified chromatographic mass spectrometry in the Full MS mode by the GC-Q-Orbitrap instrument;

3) Extract all the retention times in the chromatogram and their corresponding accurate masses, and establish an electronic ID card of all unknowns corresponding to the retention time;

4) sequentially compare the unknown electronic ID card with the electronic ID card of each pesticide compound in the electronic identity database. If ΔT ≤ 0.15 and ΔP ≤ 10%, record the pesticide compound, otherwise enter the next unknown electronic ID card. Comparison

5) The test is completed, and the information of the pesticide compound contained in the sample solution is displayed;

Where ΔT is the difference between the retention time of the unknown and the retention time of any pesticide compound in the database,

Where P _c is the intelligent matching value of the unknown, and the intelligent matching value of any pesticide compound in the P _i database.

Further, in the step 4), if ΔT ≤ 0.15 and 10% < ΔP ≤ 30%, it is judged whether or not the pesticide compound is included by the height of the mass spectrum peak and the degree of coincidence degree in the mass spectrum.

Further, step 1) pretreatment of the sample:

Weigh 10.0g sample (accurate to 0.01g) in a 100mL centrifuge tube, add 30 ~ 40mL acidified acetonitrile extract, 10000 ~ 11000rpm homogenization for 1 ~ 2min; add anhydrous magnesium sulfate and sodium chloride (mass ratio, 4: 1), shaking for 8 ~ 10min; centrifugation at 4200rpm for 5 ~ 7min, taking 15 ~ 20mL supernatant in 150mL chicken heart bottle, heated in a 40 ° C water bath rotary evaporation to 1 ~ 2mL, to be purified;

Using a CarbonNH2 column, add about 1 to 2 cm of anhydrous sodium sulfate to the CarbonNH2 column, pre-wash the SPE purification column with 5 to 6 mL of acetonitrile-toluene solution, and tap the purification column to discharge the bubbles in the column. When the liquid level is slightly higher than the top of the sodium sulfate, transfer the concentrated liquid to the purification column, and then connect the 50mL chicken heart bottle; rinse the chicken heart bottle with the sample with 2~3mL acetonitrile-toluene solution, and transfer the washing liquid to the purification column. Repeat 2~3 times; connect 25mL reservoir on the column, elute with 25~30mL acetonitrile-toluene solution; after the collection is completed, spin to evaporate to about 0.5mL, nitrogen to near dry, add 1mL ethyl acetate solution, ultrasonically dissolve It was then filtered through a 0.22 μm nylon membrane.

The beneficial effects of the invention:

1. The invention establishes an electronic ID card under the corresponding GC-Q-Orbitrap detection condition according to each pesticide compound, and innovatively utilizes the unique retention index information of each pesticide to establish an electronic identification card to assist the pesticide compound. Confirmation has greatly increased the accuracy and reliability of electronic ID cards.

2. The invention establishes an electronic identification card information unique to each pesticide, and the electronic identification card includes pesticide compound information, retention time, mass spectrum, and fragment ion information, and is optimized for improving the accuracy and operability of the alignment. The typical fragment ions are used as a basis for comparison, and the fragment ion information of the core alignment is determined by setting the base peak ions. The invention's solution makes it unnecessary to prepare pesticide standard products in food pesticide detection, and replaces the pesticide physical standard with the electronic standard screening method as a reference traditional identification method to realize high-precision, high-efficiency and resource-saving non-target pesticide residue detection. A leap in the development of pesticide residue detection technology has been realized.

3. The invention has completed the extraction of electronic ID card information of more than 600 pesticide compounds, and established a corresponding electronic identity database, which uses the theoretical accurate mass to achieve an accuracy of 5 ppm, and more importantly, through a pair of edible agricultural products. The GC-Q-Orbitrap test can simultaneously detect the residual information of multiple pesticides. After the comparison of the database, the pesticide can be quickly screened and confirmed. About 80% of the pesticide screening sensitivity is lower than the standard 10 micrograms/kg, greatly The false positive detection results are reduced, and the requirements for screening MRL levels of pesticide residues in various countries are better met.

4. Using the theoretical accurate mass as the accurate mass of the fragment ion detection, it can effectively avoid the problem of inaccurate and isotopic peaks of pesticide compounds, improve the accuracy of the whole detection, and reduce the inaccurate detection results caused by the interference of the detection equipment. Happening. The theoretical estimation method adopted by the theoretical precision quality comprehensively utilizes the cracking mechanism of the molecular structure of the pesticide compound, and further improves the establishment accuracy of the electronic ID card and the database, and improves the accuracy of the detection.

5. This patent introduces the selection model of fragment ions, which can realize the automatic and rapid selection of fragment ions. At the same time, by introducing the intelligent matching value model, the intelligent matching value of fast and automatic comparison is calculated for each compound, and the intelligent matching value takes into account the accurate quality. The information on the abundance ratio of the number and the ion, and the influence of the ion abundance of the difference between the base peak ion and the different convincing ions, which highlights the difference, reveals the original human judgment based on the introduction of the intelligent matching value. Insufficient, able to achieve accurate brake matching, truly automated detection.

DRAWINGS

Figure 1 GC-Q-Orbitrap pesticide compound electronic identity database model

Figure 2 Total ion chromatogram of the Dicofol solvent standard

Figure 3. First-order mass spectrum of the peak at Dicofol solvent standard at 19.19min

Figure 4 First-order mass spectrum of the peak at Dicofol solvent standard at 27.40min

Figure 5 Example of five representative pesticide mass spectra in the GC-Q-Orbitrap high-resolution mass spectrum library

Figure 6 Pesticide residue detection method flow

detailed description

The invention will be further described below in conjunction with the drawings and specific embodiments.

Figure 1 shows a GC-Q-Orbitrap pesticide compound electronic identity database model including an electronic identification card comprising a plurality of pesticide compounds including pesticide compound information, retention time, mass spectrum, fragment ion information, and smart match values.

Taking Dicofol as an example, the process of establishing the pesticide ID electronic ID card is described in detail:

Chromatographic conditions: The gas chromatographic column was TG-5SILMS, 30 m × 0.25 mm (i.d.) × 0.25 μm mass spectrometer dedicated column. Temperature programmed process: 40 ° C for 1 min, then programmed to 30 ° C / min to 130 ° C, then 5 ° C / min to 250 ° C, and then 10 ° C / min to 300 ° C, for 5 min; carrier gas: 氦Gas, purity ≥99.999%, flow rate 1.2mL/min; inlet type: PTV; injection volume: 1μL; injection mode: temperature-programmed injection, no split time 1.5min.

Mass spectrometry conditions: EI source voltage: 70 eV; ion source temperature: 230 ° C; transmission line temperature: 280 ° C; solvent delay: 4 min. Scanning method: Full MS; mass scanning range 50-600 m/z, resolution 60,000 FHWM (200 m/z); epoxy heptachlor used to adjust retention time; data acquisition by TraceFinder (Version. 4.0).

The PTV mode was used to test the solvent standard in Full MS mode. The molecular formula was C ₁₄ H ₉ Cl ₅ O. The total ion chromatogram of the Dicofol solvent standard is shown in Figure 2 at 19.19 min and 27.40 min. Two peaks appeared at the same time. The mass spectrum at 19.19min (Fig. 3) and the mass spectrum at 27.40min (Fig. 4) showed that although the retention times of the two peaks were inconsistent, the ion species and ion abundance were very close and could not be inferred. The ion composition and the exact mass are distinguished and identified, and for this purpose, the retention index is added to aid the judgment. The retention index of the peak at 19.19min was calculated as 1995, and the retention index of the peak at 27.40min was 2476. The retention index of Dicofol in the existing data was 2467. The retention index was found to be closer to the original retention index at 27.40min. The peak is regular, so the peak time of Dicofol is determined to be 27.40 min. It is inferred at 27.40 that the five actual measured primary fragments are 138.99464, 140.99152, 215.02583, 251.00265 and 249.99475, respectively, so that the theoretical values of the five primary fragments can be determined by combining structural information and molecular formula, respectively. C ₇ ClH ₄ O (138.99452, abundance 100.0), confirming the ion C ₇ ³⁷ ClH ₄ O (140.99157, abundance 33.2), C ₁₃ ClH ₈ O (215.02582, abundance 17.9), C ₁₃ Cl ₂ H ₉ O ( 251.00250, abundance 29.9) and C ₁₃ H ₈ OCl ₂ (249.99469, abundance 19.6), the mass deviation of the 5 ions are less than 2ppm, the intelligent matching value calculated according to the above fragment ion value is: 187.078060, the calculation process is as follows:

As shown in Figure 1, the theoretical values of Dicofol's ion-accurate mass and its fragment mass are imported into the software to build an accurate mass database, and the confirmed first-order mass spectrum is also imported into the spectral library. The above retention time information and primary mass spectrometry information constitute Dicofol's electronic identity card.

Through the manner of the above embodiments, the invention creates a large number of experimental verification work, and completes the establishment of more than 600 kinds of commonly used pesticide electronic identity databases in the world, and realizes the replacement of pesticide physical standards by electronic standards. The method optimizes and determines the GC-Q-Orbitrap screening parameters and conditions of pesticide residues, and achieves automatic comparison of test results with the pesticide electronic identity database. This process achieves high speed (40 minutes), high throughput (more than 600 types), high precision (0.00001m/z), high reliability (above 6 confirmation points), high information and automation. At the same time, a sample preparation was realized. The GC-Q-Orbitrap detection technology was used to simultaneously screen more than 600 kinds of pesticides, and the multi-indicators, non-targets and rapid screening of pesticide residues in edible agricultural products were realized; the discovery ability and method efficiency of the technology were significantly improved. Table 1 gives an example of five representative pesticide electronic IDs in the GC-Q-Orbitrap Accurate Mass Database and five representative pesticide mass spectra in the GC-Q-Orbitrap High Resolution Library. Table 2 gives a list of more than 600 pesticides in the GC-Q-Orbitrap electronic identity database.

Table 1 GC-Q-Orbitrap Examples of five pesticide compound electronic ID cards (excluding mass spectrum, chemical formula)

Table 2 List of more than 600 pesticides detected by GC-Q-Orbitrap

Figure 6 shows the method for electronic detection of pesticides according to the present invention. The sample is prepared once, and the GC-Q-Orbitrap technique can screen more than 600 kinds of pesticides; the standard product is eliminated for reference, and the electronic standard is used for qualitative identification. The replacement of physical standards with electronic ID cards has also led to a leap-forward development from targeted detection to non-targeted screening. It saves resources, reduces pollution, improves analysis speed, and fully meets the requirements of green development, environmental friendliness, and clean and efficient.

Example 1

Examples of GC-Q-Orbitrap screening and confirmation techniques for more than 600 pesticides in cabbage, including the following steps;

1. Specific steps of sample pretreatment technology:

1.1 Cabbage samples are chopped, mixed, sealed and marked with edible parts;

1.2 Weigh 10g of cabbage sample (accurate to 0.01g), add 40mL of 1% acetic acid acetonitrile in a 100mL centrifuge tube, use high-speed homogenizer 10000r/min, homogenate for 1min, add 1g sodium chloride, 4g anhydrous Magnesium sulfate, shaking for 10 min, centrifuging at 4200 r / min for 5 min, taking 20 mL of the supernatant, and concentrating to about 1 mL by rotary evaporation in a 40 ° C water bath, to be purified.

1.3 Using a Carbon NH2 column, about 2 cm of anhydrous sodium sulfate was added to the Carbon/NH2 column. Rinse the SPE column with 5mL acetonitrile + toluene (3+1, v/v), and discard the effluent. When the liquid level reaches the top of the sodium sulfate, quickly transfer the sample concentrate to the SPE column and connect it to the new one. Chicken heart bottle is received. The sample bottle was washed three times with 2 mL of acetonitrile + toluene (3+1, v/v) each time, and the washing solution was transferred to an SPE column. A 50 mL reservoir was attached to the column, and the pesticide and related chemicals were eluted with 25 mL of acetonitrile + toluene (3+1, v/v), combined in a chicken heart bottle, and concentrated in a 40 ° C water bath to about 0.5 mL.

1.4 The concentrate was dried under nitrogen, made up to volume with 1 mL of ethyl acetate, and filtered through a 0.22 μm filter for GC-Q-Orbitrap.

2, GC-Q-Orbitrap operating conditions

Chromatographic conditions: The gas chromatographic column was TG-5SILMS, 30 m × 0.25 mm (i.d.) × 0.25 μm mass spectrometer dedicated column. Temperature programmed process: 40 ° C for 1 min, then programmed to 30 ° C / min to 130 ° C, then 5 ° C / min to 250 ° C, and then 10 ° C / min to 300 ° C, for 5 min; carrier gas: 氦Gas, purity ≥99.999%, flow rate 1.2mL/min; inlet type: PTV; injection volume: 1μL; injection mode: temperature-programmed injection, no split time 1.5min.

Mass spectrometry conditions: EI source voltage: 70 eV; ion source temperature: 230 ° C; transmission line temperature: 280 ° C; solvent delay: 4 min. Scanning method: Full MS; mass scanning range 50-600 m/z, resolution 60,000 FHWM (200 m/z); epoxy heptachlor used to adjust retention time; mass spectrometry detection results collection and processing by TraceFinder (Version. 4.0); Obtain the chromatogram and mass spectrum of the cabbage under the specified chromatographic mass spectrometry, extract all the retention time in the chromatogram and its corresponding accurate mass, and establish the electronic ID of the pesticide in the cabbage corresponding to all retention time.

3. Screening of pesticide residues in cabbage

The sample solution was measured in the full scan mode, and the screening results were compared with the GC-Q-Orbitrap electronic identity database to obtain the pesticide detection. The electronic ID card of the pesticide in the cabbage is sequentially compared with the electronic ID of each pesticide compound in the electronic identity database. If (ΔT≤0.15 and ΔP≤10%), the pesticide compound is recorded if (ΔT≤0.15 and 10% < ΔP ≤ 30%), determine whether the pesticide compound is included by the height and coincidence degree of the mass spectrum peak in the mass spectrum, otherwise the electronic ID of the pesticide entering the next cabbage is compared; the detection is completed, and the display is completed. Information on pesticide compounds contained in the cabbage sample solution.

GC-Q-Orbitrap screening results in cabbage samples from a provincial capital

Twelve samples of cabbage sold in a provincial capital were collected, and more than 600 pesticide residues were screened by GC-Q-Orbitrap technique. Twelve pesticide residues were detected by GC-Q-Orbitrap technique, totaling 32 frequency, involving 12 samples. The specific results are shown in Table 3.

Table 3 GC-Q-Orbitrap screening results in cabbage samples from a region

Example 2

Examples of GC-Q-Orbitrap screening and confirmation techniques for more than 600 pesticides in tomatoes (such as the pesticides described above).

The sample pretreatment step, the GC-Q-Orbitrap operating conditions, and the pesticide residue screening process in the sample are all referred to in Example 1.

GC-Q-Orbitrap screening results in tomato samples from a provincial capital: 16 samples of commercially available tomato samples from a provincial capital were collected, and more than 600 pesticide residues were screened using GC-Q-Orbitrap technology. GC-Q-Orbitrap technique was detected. There are 16 kinds of pesticide residues, totaling 45 frequency, involving 15 samples. The specific results are shown in Table 4.

Table 4 GC-Q-Orbitrap screening results in tomato samples from a certain area

Example 3

Examples of GC-Q-Orbitrap screening and confirmation techniques for more than 600 pesticides in grapes (such as the pesticides described above).

The sample pretreatment step, the GC-Q-Orbitrap operating conditions, and the pesticide residue screening process in the sample are all referred to in Example 1.

GC-Q-Orbitrap screening results in grape samples from a provincial capital: 16 samples of grape samples from a provincial capital were collected, and more than 600 pesticide residues were screened using GC-Q-Orbitrap technology. GC-Q-Orbitrap technique was detected. There were 21 pesticide residues, totaling 73 frequency, involving 16 samples. The specific results are shown in Table 5.

Table 5 GC-Q-Orbitrap screening results in grape samples from a region

The series of detailed descriptions set forth above are merely illustrative of the possible embodiments of the present invention, and are not intended to limit the scope of the present invention. Changes are intended to be included within the scope of the invention.

Claims (10)

1. An electronic identity database of pesticide compounds in edible agricultural products based on GC-Q-Orbitrap, comprising a plurality of pesticide compound electronic identification cards, including pesticide compound information, retention time, mass spectrum, and fragment ion information, characteristics thereof Lie in:

   The pesticide compound information includes a compound name, a compound molecular formula;

   Preparing a sample of the pesticide compound, and obtaining a chromatogram of the pesticide compound under specified chromatographic mass spectrometry conditions in a Full MS mode by a GC-Q-Orbitrap apparatus, wherein the time of the peak in the chromatogram is the retention time;

   The mass spectrum is a first-level full scan obtained by the GC-Q-Orbitrap instrument at the retention time;

   The fragment ions are determined by selection in the mass spectrum, and the fragment ions include one base peak ion and a plurality of confirming ions, and the base peak ions are fragment ions having high signal intensity and large mass, the base peak The ion does not select the ion of the isotope peak;

   The fragment ion information includes an ion abundance ratio and a theoretical accurate mass number;

   The ion abundance ratio is a signal intensity ratio of the fragment ion to the base peak ion;

   The database is sorted according to the retention time in the electronic ID card.
2. The electronic identity database of a pesticide compound in an edible agricultural product based on GC-Q-Orbitrap according to claim 1, wherein the electronic identity database further comprises an intelligent matching model, and the matching model is added to the electronic identity card. The intelligent matching value P _m , whose calculation model is:

   

   

   W _b + W _q =1;

   Where M _b is the theoretical exact mass of the base peak ion, M _i is the exact mass of the ith confirmed ion, W _i is the weight of the ith confirmed ion, and I _i is the ion abundance ratio of the ith confirmed ion It is confirmed that the order of ions is from the largest to the smallest of the ion abundance ratio; W _b is the weight of the base peak ions, W _q is the comprehensive weight of the confirmed ions, and n is the number of fragment ions.
3. The electronic identity database of pesticide compounds in edible agricultural products based on GC-Q-Orbitrap according to claim 1, wherein the W _b and W _q can be adjusted according to changes in the intelligent matching model, and the general value is W _b = W _q = 0.5.
4. The electronic identity database of pesticide compounds in edible agricultural products based on GC-Q-Orbitrap according to claim 1 or 2, wherein the selection of the fragment ions is based on ion abundance and ion mass number, The degree is the signal intensity of the ions in the mass spectrum, the number of the fragment ions is five, and the principle of the fragment ion selection is:

   If ΔI>10%, take the maximum value of I _i , I _j ; otherwise take the maximum value of M _i , M _j ;

   Where: I _i , I _j are the ion abundance ratios of the two closest fragment ions, ΔI=|I _i -I _j |, M _i , M _j are the exact masses of the two closest fragment ions, The arrangement of the ion fragments is in accordance with the ion abundance ratio from large to small.
5. The electronic identity database of pesticide compounds in edible agricultural products based on GC-Q-Orbitrap according to claim 1 or 2, wherein the theoretical accurate mass of the fragment ions is determined by:

   1) clarify the composition of the fragment ion element according to the molecular formula of the compound;

   2) According to the mass number M of the fragment ions in the mass spectrum, a list of possible fragment ion element compositions is obtained by calculation;

   

   Where: M _i is the exact mass of the i-th fragment ion element, n is the number of elements of the fragment ion, and y _i is the number of elements corresponding to the i-th fragment ion.

   3) Select a reasonable fragment ion element composition from the list of fragment ion element composition by the molecular structure cracking mechanism, and calculate its theoretical exact mass M'.

   M'=M ₁ y' ₁ +M ₂ y' ₂ +...+M _n y' _n

   Wherein: M ₁ , M _{2 ,} ..., M _n is the exact mass of the fragment ion element, and y' ₁ , y' ₂ , ... y' _n are the number of corresponding elements of the preferred fragment ion element composition.
6. The electronic identity database of a pesticide compound in an edible agricultural product based on GC-Q-Orbitrap according to claim 1 or 2, wherein the pesticide compound is calculated when two or more peaks appear in the chromatogram a retention index determining the retention time of the pesticide compound by the degree to which the retention index is close to the standard retention index of the pesticide compound;

   The calculation method of the retention index R _I is:

   

   The t _R is a corrected retention time, and the z and z+1 are respectively the number of carbon atoms contained in the normal paraffin before and after the leaching of the pesticide compound (x), and the t _R (z) < t _R (x) < t _R (z+1), the number z of carbon atoms contained in normal paraffins in a general pesticide compound is greater than 4.
7. The pesticide-based compound electronic identity database for edible agricultural products based on GC-Q-Orbitrap according to claim 1 or 2, wherein the chromatographic mass spectrometry conditions are:

   Chromatographic conditions: GC column is TG-5SILMS, 30m × 0.25mm (id) × 0.25μm special column for mass spectrometry; temperature programming process: 40 ° C for 1 min, then programmed to 30 ° C / min to 130 ° C, then 5 ° C /min warmed to 250 ° C, and then heated to 300 ° C at 10 ° C / min, held for 5 min; carrier gas: helium, purity ≥ 99.999%, flow rate 1.2mL / min; inlet type: PTV; injection volume: 1μL ; injection method: temperature programmed injection, no split time 1.5min;

   Mass spectrometry conditions: EI source voltage: 70 eV; ion source temperature: 230 ° C; mass spectrometry end transfer line temperature: 280 ° C; solvent delay: 4 min. Scanning mode: Full MS; mass scanning range 50-600 m/z, resolution 60,000 FHWM (200 m/z); epoxy heptachlor was used to adjust retention time.
8. A method for detecting pesticide compounds in edible agricultural products based on GC-Q-Orbitrap, comprising:

   1) The sample to be tested is extracted by homogenization of acetic acid acetonitrile, dehydrated, centrifuged, concentrated, and then purified by Carbon/NH2 column, and the residual pesticide is eluted by acetonitrile + toluene, and concentrated and filtered to prepare a sample solution to be tested;

   2) Obtain a chromatogram and a mass spectrum of the sample solution under the specified chromatographic mass spectrometry in the Full MS mode by the GC-Q-Orbitrap instrument;

   3) Extract all the retention times in the chromatogram and their corresponding accurate masses, and establish an electronic ID card of all unknowns corresponding to the retention time;

   4) sequentially comparing the unknown electronic ID card with the electronic identification card of each pesticide compound in the electronic identity database of claim 2, if ΔT ≤ 0.15 and ΔP ≤ 10%, recording the pesticide compound, otherwise entering the next unknown Comparison of electronic ID cards;

   5) The test is completed, and the information of the pesticide compound contained in the sample solution is displayed;

   Where ΔT is the difference between the retention time of the unknown and the retention time of any pesticide compound in the database,

   

   Where P _c is the intelligent matching value of the unknown, and the intelligent matching value of any pesticide compound in the P _i database.
9. The method for detecting a pesticide compound in an edible agricultural product based on GC-Q-Orbitrap according to claim 8, wherein in step 4), if ΔT ≤ 0.15 and 10% < ΔP ≤ 30%, passing through the mass spectrum The height of the mass spectrum peak and the degree of coincidence determination determine whether or not the pesticide compound is included.
10. The method for detecting a pesticide compound in an edible agricultural product based on GC-Q-Orbitrap according to claim 8, wherein the step 1) pretreatment of the sample:

    Weigh 10.0g sample (accurate to 0.01g) in a 100mL centrifuge tube, add 30 ~ 40mL acidified acetonitrile extract, 10000 ~ 11000rpm homogenization for 1 ~ 2min; add anhydrous magnesium sulfate and sodium chloride (mass ratio, 4: 1), shaking for 8 ~ 10min; centrifugation at 4200rpm for 5 ~ 7min, taking 15 ~ 20mL supernatant in 150mL chicken heart bottle, heated in a 40 ° C water bath rotary evaporation to 1 ~ 2mL, to be purified;

    Using a CarbonNH2 column, add about 1 to 2 cm of anhydrous sodium sulfate to the CarbonNH2 column, pre-wash the SPE purification column with 5 to 6 mL of acetonitrile-toluene solution, and tap the purification column to discharge the bubbles in the column. When the liquid level is slightly higher than the top of the sodium sulfate, transfer the concentrated liquid to the purification column, and then connect the 50mL chicken heart bottle; rinse the chicken heart bottle with the sample with 2~3mL acetonitrile-toluene solution, and transfer the washing liquid to the purification column. Repeat 2~3 times; connect 25mL reservoir on the column, elute with 25~30mL acetonitrile-toluene solution; after the collection is completed, spin to evaporate to about 0.5mL, nitrogen to near dry, add 1mL ethyl acetate solution, ultrasonically dissolve It was then filtered through a 0.22 μm nylon membrane.

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