A novel method and system for non-targeted screening of contaminants

Abstract

The application belongs to the technical field of environmental analysis chemistry, and discloses a new pollutant non-target screening method and system, which combines FT-ICR-MS and Orbitrap mass spectrum data to perform non-target screening of new pollutants, and comprises the following steps: acquiring FT-ICR-MS and Orbitrap mass spectrum data of a sample to be measured; performing peak extraction respectively to construct FT-ICR-MS peak tables and Orbitrap peak tables; performing cross-platform peak matching; replacing mass numbers corresponding to each peak in the Orbitrap peak table with mass numbers of corresponding peaks matched in the FT-ICR-MS peak table to obtain joint peak tables; performing substance structure analysis based on the joint peak tables to output screening results. The application has the high-throughput advantage of Orbitrap and the mass accuracy advantage of FT-ICR-MS, and can significantly improve the accuracy, sensitivity and structure inference confidence of non-target screening of new pollutants.

Description

Technical Field

[0001] This invention relates to the field of environmental analytical chemistry technology, and in particular to a novel non-targeted screening method and system for pollutants, which combines FT-ICR-MS (Fourier Transform Ion Cyclotron Resonance Mass Spectrometry) and Orbitrap (Liquid Chromatography-Quadrupole Ion Trap Electrostatic Orbit Ion Trap Tri-Synthesis Mass Spectrometry) mass spectrometry data. Background Technology

[0002] With the advancement of industrialization and modernization of production processes, a large number of new pollutants not yet included in regulation (including novel industrial chemicals, environmental conversion products, packaging material residues, pesticide / drug metabolites, etc.) are constantly entering the environmental media. Current non-targeted analysis of new pollutants mainly relies on high-resolution mass spectrometry (HRMS). Among them, Orbitrap mass spectrometry has advantages such as fast scanning speed and high throughput, while FT-ICR MS, with its sub-ppm mass accuracy and extremely high resolution, has become a key technology for identifying unknown compounds in complex samples.

[0003] However, while Orbitrap mass spectrometry offers advantages such as fast scanning speed, rich MS / MS information, and suitability for large-scale non-targeted screening, its mass accuracy is typically limited to 1–5 ppm due to factors like temperature drift and charge accumulation, making it unsuitable for high-confidence structure inference. FT-ICR MS, on the other hand, boasts high mass accuracy but suffers from low throughput and limited scanning speed, hindering its coverage of a wider range of potential compounds. Furthermore, both methods lack a unified data processing workflow.

[0004] Therefore, it is necessary to develop a novel non-targeted screening method that combines the quality accuracy of FT-ICR MS with the rapid scanning advantage of Orbitrap to achieve a more comprehensive and higher-confidence identification of new pollutants. Summary of the Invention

[0005] To address the limitations of existing technologies, such as the limited accuracy of Orbitrap mass spectrometry data and the limited scanning speed of FT-ICR MS mass spectrometry data, this invention proposes a novel non-targeted pollutant screening method. By combining the ultra-high mass accuracy of FT-ICR MS with the high-throughput scanning capability of Orbitrap, and by constructing peak table matching and mass replacement algorithms, the precise mass measured by FT-ICR MS is replaced on the Orbitrap peak table, thereby improving the mass accuracy of Orbitrap peaks in FT-ICR MS and significantly enhancing the screening capability for unknown pollutants.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a novel non-targeted screening method for pollutants, comprising the following steps: Step 1: Obtain the mass spectrometry data of the sample to be tested, including FT-ICR-MS mass spectrometry data and Orbitrap mass spectrometry data; Step 2: Perform peak extraction on the FT-ICR-MS mass spectrometry data and Orbitrap mass spectrometry data respectively, and construct the FT-ICR-MS peak table and Orbitrap peak table based on the extraction results; Step 3: Perform cross-platform peak matching on the FT-ICR-MS peak table and the Orbitrap peak table to find the corresponding peaks in the FT-ICR-MS peak table for each peak in the Orbitrap peak table; Step 4: Based on the matching results, replace the mass number of each peak in the Orbitrap peak table with the mass number of the corresponding peak matched in the FT-ICR-MS peak table to obtain the joint peak table; Step 5: Perform material structure analysis based on the combined peak table; based on the material structure analysis results, output the screening results for new pollutants.

[0007] In step 3, cross-platform peak matching is performed using mass numbers. During matching, the mass numbers of each peak in the FT-ICR-MS mass spectrometry data and the Orbitrap mass spectrometry data are compared, and peaks with a mass number difference less than a threshold are paired.

[0008] The threshold is 1 ppm.

[0009] In step 4, the mass numbers of each parent ion peak corresponding to the first-level mass spectrometry in the Orbitrap peak table are replaced with the mass numbers of the corresponding peaks matched in the FT-ICR-MS peak table to obtain a joint peak table.

[0010] In step 2, the method for peak extraction of the FT-ICR-MS mass spectrometry data is as follows: the initial mass spectrometry data is screened based on a preset signal-to-noise ratio, and mass spectrometry data with a signal-to-noise ratio greater than or equal to the preset signal-to-noise ratio are retained to obtain the FT-ICR-MS peak table; The method for peak extraction from the Orbitrap mass spectrometry data is as follows: peaks with a fold change > 5 and p < 0.05 are selected as characteristic peaks and retained, and an Orbitrap peak table is formed based on the data corresponding to the characteristic peaks.

[0011] In step 2, the FT-ICR-MS peak information includes: molecular formula and mass ratio, and the Orbitrap peak information includes: retention time, mass ratio, peak intensity, peak area, and signal-to-noise ratio.

[0012] In step 5, the method for structural analysis of substances based on the joint peak table is as follows: The primary and secondary mass spectrometry peak tables in the combined peak table are matched with the internal database. During matching, the following tolerance thresholds are set: retention time tolerance threshold is 0.1 min, primary mass spectrometry peak table mass accuracy tolerance threshold is 10 ppm, and secondary mass spectrometry information mass accuracy tolerance threshold is 0.015 Da. After matching is completed, a reliability level is assigned to each compound, and the final new pollutant screening result list is generated.

[0013] In step 5, the output of the new pollutant screening results includes the substance name, SMILES, Inchikey, purpose, category, detection rate, and relative abundance.

[0014] Furthermore, the present invention also provides a novel non-targeted pollutant screening system for implementing the aforementioned novel non-targeted pollutant screening method, comprising: Data acquisition module: used to acquire mass spectrometry data of the sample to be tested, including FT-ICR-MS mass spectrometry data and Orbitrap mass spectrometry data; Peak extraction module: Perform peak extraction on the FT-ICR-MS mass spectrometry data and Orbitrap mass spectrometry data respectively, and construct FT-ICR-MS peak table and Orbitrap peak table based on the extraction results; Peak matching module: used to perform cross-platform peak matching between FT-ICR-MS peak table and Orbitrap peak table, and find the corresponding peak in FT-ICR-MS peak table for each peak in Orbitrap peak table; The quality replacement module is used to replace the quality number of each peak in the Orbitrap peak table with the quality number of the corresponding peak matched in the FT-ICR-MS peak table based on the matching results, thus obtaining a joint peak table. Screening module: used to perform material structure analysis based on the joint peak table, and output screening results for new pollutants based on the material structure analysis results.

[0015] Compared with the prior art, the present invention has the following advantages: This invention proposes a novel non-targeted screening method and system for pollutants. By combining the ultra-high quality accuracy of FT-ICR MS with the high-throughput scanning capability of Orbitrap, and by constructing peak table matching and quality replacement algorithms, the precise quality measured by FT-ICR MS is replaced on the Orbitrap peak table, thereby improving the quality accuracy of Orbitrap peaks compared to FT-ICR MS. This significantly enhances the screening capability for unknown pollutants and enables more comprehensive and higher-confidence identification of new pollutants. Attached Figure Description

[0016] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings.

[0017] Figure 1 This is a flowchart of a novel non-targeted pollutant screening method provided in Embodiment 1 of the present invention; Figure 2 This describes the category composition of new pollutants in the Fenhe River Basin in Embodiment 2 of the present invention. Figure 3 The detection rate distribution of new pollutants in the Fenhe River Basin in Embodiment 2 of the present invention; Figure 4 This is the distribution of substances with a detection rate greater than 50% in the Fenhe River Basin in Embodiment 2 of the present invention across various scenarios; Detailed Implementation To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Example 1 like Figure 1 As shown, Embodiment 1 of the present invention proposes a novel non-targeted screening method for pollutants, comprising the following steps: Step 1: Obtain the target mass spectrometry data of the sample to be tested.

[0019] The samples to be tested can be obtained from the water area to be tested. For example, in this embodiment, if it is necessary to detect new pollutants in a water sample from a certain watershed, then water samples can be collected from multiple typical scenes and cross sections (upstream, midstream, and downstream) of the watershed to obtain the samples to be tested. A total of 19 water samples were obtained. After solid-phase extraction and enrichment, FT-ICR-MS (Fourier Transform Ion Cyclotron Resonance Mass Spectrometry) data were obtained, and Orbitrap (Electrostatic Field Orbit Trap Mass Spectrometry) data were obtained for the full scan.

[0020] After obtaining the sample to be tested, and before obtaining the target mass spectrometry data of the sample to be tested, the sample to be tested can be enriched and extracted according to the following steps to obtain the target sample: S110: Pre-treat the sample.

[0021] In this embodiment, a glass fiber filter (0.7 μm pore size) can be used for filtration to remove suspended impurities. The pH of the sample to be tested is adjusted to 6.0-6.5 based on ammonium acetate and / or formic acid.

[0022] S120: Solid phase extraction of the sample.

[0023] The sample to be tested after the first filtration was subjected to solid-phase extraction to obtain the target sample.

[0024] In the embodiments of this application, solid phase extraction can be performed using a mixed column filtration method.

[0025] In the embodiments of this application, when a mixed column filtration is used, the flow rate of the sample to be tested through the filter column can be 4-6 mL / min.

[0026] After the sample to be tested has undergone the first filtration, the target sample can be obtained by solid-phase extraction. The target mass spectrometry data of the sample to be tested can then be detected based on the target sample.

[0027] In the embodiments of this application, the target mass spectrometry data can be obtained through the following steps S130-S140.

[0028] S130: Determine the initial FT-ICR-MS mass spectrometry data of the target sample based on FT-ICR MS.

[0029] In the embodiments of this application, 15.0 T FT-ICR MS can be used to obtain target mass spectrometry data based on the target sample obtained by solid phase extraction.

[0030] In this embodiment of the application, before determining the mass spectrometry data of the target sample based on FT-ICR MS, the FT-ICR MS can be tuned and calibrated based on sodium formate solution. The concentration of sodium formate solution used for tuning can be 10 mmol / L. After tuning, a blank water sample is used to perform background correction on the FT-ICR MS.

[0031] After tuning, calibrating, and background correcting the FT-ICR MS, the target sample can be input into the FT-ICRMS. The mass spectrometry acquisition range is 180-1000 Da.

[0032] Through step S130, initial FT-ICR-MS mass spectrometry data can be obtained based on the target sample using FT-ICR-MS.

[0033] S140: Obtain the initial Orbitrap mass spectrometry data of the target sample based on Orbitrap.

[0034] In the embodiments of this application, the Ultimate 3000-Orbitrap Fusion can be used to obtain target mass spectrometry data based on the target sample obtained by solid-phase extraction.

[0035] In this embodiment, before measuring the Orbitrap mass spectrometry data of the target sample based on Orbitrap, the mass spectrometry calibration and tuning are performed externally by directly injecting a mixture of positive and negative standards. Before the analysis run, the performance of the Orbitrap is monitored by checking the tuning; the mass error under all test conditions is less than 0.5 ppm.

[0036] In this embodiment, two independent detections were performed in point spray positive ion mode and negative ion mode respectively to complete the non-targeted analysis data acquisition. The column temperature was 40℃, and the injection volume was 10 μL. The full scan mass spectrometry (MS1) acquisition mass range was 100-1000 m / z, the resolution was 120,000 fwhm (fwhm at m / z 200), the maximum injection time was set to 50 ms, and the AGC target value was 1.0 e5. For t-MS2 mode, MS1 precursor ions were first selected by quadrupole with an isolation window of 1.6 m / z, and then transferred to ion transport multistage for MS2 fragmentation. The HCD fragmentation energy was 30±15%, the resolution was 30,000 (fwhm at m / z 200), the maximum injection time was set to 54 ms, and the AGC target value was 5e4.

[0037] In step S140, Orbitrap mass spectrometry data can be obtained based on the target sample using Orbitrap.

[0038] Step 2: Perform peak extraction on the FT-ICR-MS mass spectrometry data and Orbitrap mass spectrometry data respectively, and construct the FT-ICR-MS peak table and Orbitrap peak table based on the extraction results.

[0039] In step 2, the method for peak extraction of the FT-ICR-MS mass spectrometry data is as follows: the initial mass spectrometry data is screened based on a preset signal-to-noise ratio, and mass spectrometry data with a signal-to-noise ratio greater than or equal to the preset signal-to-noise ratio are retained to obtain the FT-ICR-MS peak table; specifically, the preset signal-to-noise ratio is set to 5.

[0040] The method for peak extraction from the Orbitrap mass spectrometry data is as follows: peaks with a fold change > 5 and p < 0.05 are selected as characteristic peaks and retained, and an Orbitrap peak table is formed based on the data corresponding to the characteristic peaks; Specifically, in this embodiment, for Orbitrap mass spectrometry data, since the chromatographic peaks of the isotopic and adduct forms of the compound (i.e., H+, Na+, K+, NH4+, etc.) have the same retention time, potential isotopic or adduct relationships between different forms of the same compound are marked. Because the same substance in different samples may have different retention time-mass pairs during sample analysis, and the retention time and mass of the same substance may shift to some extent, the difficulty of comparative analysis is increased. Therefore, an alignment algorithm is used, which groups the peaks corresponding to retention time-mass pairs with a retention time difference <0.1 minutes and a mass difference <0.015 Da into the same group. Subsequently, the peak areas of the aligned retention time-mass pairs are obtained in each sample and blank for further comparison. The peaks of a specific retention time-mass pair in each sample are compared with the peaks of the same retention time-mass pair in the blank sample. Based on the previous alignment algorithm that has obtained the peak area of ​​all retention time-quality pairs in the blank, peaks with a fold change (experimental peak area / blank peak area) > 5 and a significance p < 0.05 are selected as characteristic peaks and retained to form a list of characteristic peaks, which is the Orbitrap peak table.

[0041] Step 3: Perform cross-platform peak matching on the FT-ICR-MS peak table and the Orbitrap peak table to find the corresponding peaks in the FT-ICR-MS peak table for each peak in the Orbitrap peak table.

[0042] In step 3, cross-platform peak matching is performed using mass numbers. During matching, the mass numbers of each peak in the FT-ICR-MS mass spectrometry data and the Orbitrap mass spectrometry data are compared, and peaks with a mass number difference less than a threshold are paired.

[0043] Specifically, in this embodiment, the threshold for the mass number difference is set to δ=1 ppm.

[0044] Step 4: Based on the matching results, replace the mass number of each peak in the Orbitrap peak table with the mass number of the corresponding peak matched in the FT-ICR-MS peak table to obtain the joint peak table.

[0045] Specifically, in this embodiment, the Orbitrap mass spectrometry includes a primary mass spectrometry and a secondary mass spectrometry. In step 4, the mass numbers of each parent ion peak corresponding to the primary mass spectrometry in the Orbitrap peak table are replaced with the mass numbers of the corresponding peaks matched in the FT-ICR-MS peak table. The Orbitrap peak table after replacing the mass numbers is the joint peak table.

[0046] Step 5: Perform material structure analysis based on the combined peak table; based on the material structure analysis results, output the screening results for new pollutants.

[0047] Step 5, the analysis of material structure specifically includes the following analysis process: characteristic peak clustering, isotope cluster identification, adduct identification and structure annotation.

[0048] In this embodiment, structural annotation of substances is performed, and the peak tables corresponding to the primary and secondary mass spectrometry information of Orbitrap mass spectrometry data are matched with an internal database. During MS / MS fragment comparison, a potential structural relationship between the precursor and its fragment ion characteristics can be established according to the diagnostic fragment ion (DFI) strategy. Spectra with specific precursors and retention times are assigned to characteristic peaks with corresponding retention times and masses. The spectra of any two characteristic peaks are compared using an algorithm, and fragments with the same characteristics are labeled. Subsequently, a confidence level is assigned to each compound, generating a final list of new contaminant screening results. For database matching, the following specific tolerance thresholds are set: a tolerance threshold of 0.1 min for retention time (RT), a tolerance threshold of 10 ppm for primary mass spectrometry (MS1) mass accuracy, and a fragment mass accuracy of 0.015 Da for secondary mass spectrometry (MS2).

[0049] Specifically, in step 5, the output of the new pollutant screening results includes the substance name, SMILES (molecular linear code), Inchikey (standard chemical identification code), purpose, category, detection rate, and relative abundance.

[0050] In this embodiment, non-targeted screening of new pollutants is achieved through deep processing using pyhrms.

[0051] Example 2 like Figure 1 As shown, Embodiment 2 of the present invention provides a new non-targeted pollutant screening method using multiple typical scenarios and sections (upstream, midstream, and downstream) in the Fenhe River Basin as examples, specifically including the following steps: Step 1: Obtain the mass spectrometry data of the sample to be tested, including FT-ICR-MS mass spectrometry data and Orbitrap mass spectrometry data.

[0052] Sample preparation: Sampling was conducted upstream and downstream along the Fenhe River basin during the dry and wet seasons (April and August 2024), covering 19 sampling points including coal chemical plants (IO), national monitoring sections (NS), tributary inlets (TI), livestock breeding sources (LO), and urban domestic sources (MO). The samples to be tested were mixed samples collected over multiple days or at multiple time periods, with a volume of 2L. The sampling points were ideally located approximately 3m from the riverbank and 0.5m from the water surface. All samples were collected in pre-cleaned high-density polyethylene bottles, stored in well-sealed containers with ice packs, and immediately transported back to the laboratory. They were stored at 4℃ until pretreatment (the entire period should not exceed 7 days).

[0053] The target sample was enriched and extracted from the sample to be tested: The pH of the river water sample was first adjusted to 6.0-6.5 using formic acid, and then filtered for the first time through a glass fiber filter (GF / F, Whatman, 0.7 μm effective pore size). Then, solid-phase extraction was performed, and the sample was passed through a mixed column at a flow rate of about 5 ml / min. After extraction, the mixed column was rinsed with 12 mL of ultrapure water. Then, the mixed column was dried with gentle nitrogen gas until it was fine sand-like. The sample compound was eluted into a 15 mL glass centrifuge tube with 6 mL of ethyl acetate / methanol (1:1, v / v) containing 2% ammonia and 3 mL of ethyl acetate / methanol (1:1, v / v) containing 1.7% formic acid. The sample was then dried with nitrogen evaporator, redissolved in methanol to 1 mL, and filtered through a 0.22 μm organic phase filter membrane to obtain the target sample. The sample was then transferred to a brown chromatographic bottle and stored at -20℃.

[0054] FT-ICR-MS mass spectrometry data of the target sample: The target river water sample was analyzed using a 15.0T FT-ICR-MS in negative ionization mode. Before detection, the FT-ICR-MS was tuned and calibrated with 10 mmol / L sodium formate solution, and background correction was performed using a blank water sample. After calibration, the target sample injection rate was set to 120 µL / h, the capillary inlet voltage to -3800 V, and the mass spectrometry data acquisition range to 180-1000 Da. Each sample was scanned an average of 200 times under an electrospray ionization source. After each injection of the target sample, the syringe and related fluid lines were flushed three times with a methanol / water solution (1:1, v / v). After the above treatment, initial mass spectrometry data were obtained, and the error of the initial mass spectrometry was controlled within 0.2 ppm.

[0055] Orbitrap mass spectrometry data of the target sample were obtained: Two independent detections were performed using an Ultimate 3000-Orbitrap Fusion column in both point spray positive and negative ion modes to complete data acquisition. Liquid chromatography separation was performed using a Hypersil GOLD aQ column (150 mm × 2.1 mm, 1.9 μm, Thermo Fisher Scientific, Bellefonte, PA). The mobile phase consisted of water (HPLC grade, phase A) and acetonitrile (HPLC grade, phase B), both containing 0.1% formic acid (HPLC grade). The mobile phase flow rate was set to 0.1 mL min⁻¹. The column temperature was 40 °C, and the injection volume was 10 μL. The initial gradient elution conditions were 5% phase B, maintained for 1.0 min; within 1.0–19.0 ​​min, the phase B content linearly increased from 5% to 100% and maintained for 6.5 min. The column was equilibrated within 0.1 min (i.e., from 23.5 min to 23.6 min), and the gradient program ended.

[0056] The mass spectrometry parameters were set as follows: nebulizer temperature was set to 350℃, ion transfer tube temperature to 320℃, spray voltage to 3200 V, sheath gas flow rate to 40 au, and auxiliary gas flow rate to 10 au. Full-scan mass spectrometry (MS1) was used with a mass acquisition range of 100-1000 m / z, a resolution of 120,000 fwhm (fwhm at m / z 200), a maximum injection time of 50 ms, and an AGC target value of 1.0 e5. For t-MS2 mode, MS1 precursor ions were first selected via a quadrupole with an isolation window of 1.6 m / z, followed by MS2 fragmentation via an ion transfer multistage. The HCD fragmentation energy was 30 ± 15%, the resolution was 30,000 (fwhm at m / z 200), the maximum injection time was 54 ms, and the AGC target value was 5e4. Mass spectrometry calibration and tuning were performed externally by directly injecting a mixture of positive and negative standards. Before the analysis run, the performance of Oribitrap was monitored by checking the tuning, and the quality error under all test conditions was less than 0.5 ppm.

[0057] Step 2: Perform peak extraction on the FT-ICR-MS mass spectrometry data and Orbitrap mass spectrometry data respectively, and construct the FT-ICR-MS peak table and Orbitrap peak table based on the extraction results; After obtaining the initial FT-ICR-MS mass spectrometry data, the initial mass spectrometry data is filtered based on a preset signal-to-noise ratio of 5 to obtain target mass spectrometry data with a signal-to-noise ratio greater than or equal to 5, and then peak extraction is performed.

[0058] The method for peak extraction from the Orbitrap mass spectrometry data is as follows: peaks with a fold change > 5 and p < 0.05 are selected as characteristic peaks and retained, and an Orbitrap peak table is formed based on the data corresponding to the characteristic peaks.

[0059] Step 3: Perform cross-platform peak matching on the FT-ICR-MS peak table and the Orbitrap peak table to find the corresponding peaks in the FT-ICR-MS peak table for each peak in the Orbitrap peak table.

[0060] Under the condition of a preset quality difference threshold δ (preferably 1 ppm), cross-platform matching is performed on the two peak tables to determine the corresponding peak pairs.

[0061] Step 4: Based on the matching results, replace the mass number of each peak in the Orbitrap peak table with the mass number of the corresponding peak matched in the FT-ICR-MS peak table to obtain the joint peak table.

[0062] Based on the matching results, the exact mass numbers in the FT-ICR MS peak table are replaced with the corresponding peaks in the Orbitrap peak table to obtain a joint peak table.

[0063] Step 5: Perform material structure analysis based on the combined peak table; based on the material structure analysis results, output the screening results for new pollutants.

[0064] During material structure analysis, primary and secondary mass spectrometry information was matched against an internal database. A confidence level was then assigned to each compound, generating a final list of new contaminant screening results. For database matching, the following specific tolerance thresholds were set: retention time (RT) of 0.1 min, MS1 mass accuracy of 10 ppm, and MS2 fragment mass accuracy of 0.015 Da.

[0065] like Figure 2 , Figure 3 and Figure 4 As shown, a total of 1242 ROPs were detected in the Fenhe River Basin, including 439 pharmaceuticals, 368 human metabolites, 103 pesticides, 74 personal care products, 48 ​​plasticizers, and industrial chemicals. Pharmaceuticals accounted for the largest share at 35.3%, followed by human metabolites at 29.6%, natural toxins at 12%, and pesticides at 8.3%, with the top four categories totaling 85%. 64 ROPs had a detection rate >50%. This result exhibits typical environmental non-targeting characteristics, with a few pollutants widely present and many pollutants appearing only in localized sampling sites. The detection rates were higher in MO, LO, and TI scenarios, and the composition of ROPs was more complex. Amantadine and telmisartan had a detection rate of 100%.

[0066] Example 3 Embodiment 3 of the present invention provides a novel non-targeted screening system for pollutants, used to implement the aforementioned novel non-targeted screening method for pollutants, comprising: Data acquisition module: used to acquire mass spectrometry data of the sample to be tested, including FT-ICR-MS mass spectrometry data and Orbitrap mass spectrometry data; Peak extraction module: Perform peak extraction on the FT-ICR-MS mass spectrometry data and Orbitrap mass spectrometry data respectively, and construct FT-ICR-MS peak table and Orbitrap peak table based on the extraction results; Peak matching module: used to perform cross-platform peak matching between FT-ICR-MS peak table and Orbitrap peak table, and find the corresponding peak in FT-ICR-MS peak table for each peak in Orbitrap peak table; The quality replacement module is used to replace the quality number of each peak in the Orbitrap peak table with the quality number of the corresponding peak matched in the FT-ICR-MS peak table based on the matching results, thus obtaining a joint peak table. Screening module: used to perform material structure analysis based on the joint peak table, and output screening results for new pollutants based on the material structure analysis results.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A novel non-targeted screening method for pollutants, characterized in that, Includes the following steps: Step 1: Obtain the mass spectrometry data of the sample to be tested, including FT-ICR-MS mass spectrometry data and Orbitrap mass spectrometry data; Step 2: Perform peak extraction on the FT-ICR-MS mass spectrometry data and Orbitrap mass spectrometry data respectively, and construct the FT-ICR-MS peak table and Orbitrap peak table based on the extraction results; Step 3: Perform cross-platform peak matching on the FT-ICR-MS peak table and the Orbitrap peak table to find the corresponding peaks in the FT-ICR-MS peak table for each peak in the Orbitrap peak table; Step 4: Based on the matching results, replace the mass number of each peak in the Orbitrap peak table with the mass number of the corresponding peak matched in the FT-ICR-MS peak table to obtain the joint peak table; Step 5: Perform material structure analysis based on the combined peak table; based on the material structure analysis results, output the screening results for new pollutants.

2. The novel non-targeted screening method for pollutants according to claim 1, characterized in that, In step 3, cross-platform peak matching is performed using mass numbers. During matching, the mass numbers of each peak in the FT-ICR-MS mass spectrometry data and the Orbitrap mass spectrometry data are compared, and peaks with a mass number difference less than a threshold are paired.

3. The novel non-targeted screening method for pollutants according to claim 2, characterized in that, The threshold is 1 ppm.

4. The novel non-targeted screening method for pollutants according to claim 1, characterized in that, In step 4, the mass numbers of each parent ion peak corresponding to the first-level mass spectrometry in the Orbitrap peak table are replaced with the mass numbers of the corresponding peaks matched in the FT-ICR-MS peak table to obtain a joint peak table.

5. The novel non-targeted screening method for pollutants according to claim 1, characterized in that, In step 2, the method for peak extraction of the FT-ICR-MS mass spectrometry data is as follows: the initial mass spectrometry data is screened based on a preset signal-to-noise ratio, and mass spectrometry data with a signal-to-noise ratio greater than or equal to the preset signal-to-noise ratio are retained to obtain the FT-ICR-MS peak table; The method for peak extraction from the Orbitrap mass spectrometry data is as follows: peaks with a fold change > 5 and p < 0.05 are selected as characteristic peaks and retained, and an Orbitrap peak table is formed based on the data corresponding to the characteristic peaks.

6. The novel non-targeted screening method for pollutants according to claim 1, characterized in that, In step 2, the FT-ICR-MS peak information includes: molecular formula and mass ratio, and the Orbitrap peak information includes: retention time, mass ratio, peak intensity, peak area, and signal-to-noise ratio.

7. The novel non-targeted screening method for pollutants according to claim 1, characterized in that, In step 5, the method for structural analysis of substances based on the joint peak table is as follows: The primary and secondary mass spectrometry peak tables in the combined peak table are matched with the internal database. During matching, the following tolerance thresholds are set: retention time tolerance threshold is 0.1 min, primary mass spectrometry peak table mass accuracy tolerance threshold is 10 ppm, and secondary mass spectrometry information mass accuracy tolerance threshold is 0.015 Da. After matching is completed, a reliability level is assigned to each compound, and the final new pollutant screening result list is generated.

8. The novel non-targeted screening method for pollutants according to claim 1, characterized in that, In step 5, the output of the new pollutant screening results includes the substance name, SMILES, Inchikey, purpose, category, detection rate, and relative abundance.

9. A novel non-targeted screening system for pollutants, used to implement the novel non-targeted screening method for pollutants as described in any one of claims 1 to 8, characterized in that, include: Data acquisition module: used to acquire mass spectrometry data of the sample to be tested, including FT-ICR-MS mass spectrometry data and Orbitrap mass spectrometry data; Peak extraction module: Perform peak extraction on the FT-ICR-MS mass spectrometry data and Orbitrap mass spectrometry data respectively, and construct FT-ICR-MS peak table and Orbitrap peak table based on the extraction results; Peak matching module: used to perform cross-platform peak matching between FT-ICR-MS peak table and Orbitrap peak table, and find the corresponding peak in FT-ICR-MS peak table for each peak in Orbitrap peak table; The quality replacement module is used to replace the quality number of each peak in the Orbitrap peak table with the quality number of the corresponding peak matched in the FT-ICR-MS peak table based on the matching results, thus obtaining a joint peak table. Screening module: used to perform material structure analysis based on the joint peak table, and output screening results for new pollutants based on the material structure analysis results.

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