A method for detecting contraband compounds in a complex matrix

Abstract

The present application relates to atmospheric pressure ion manipulation technology, specifically, the present application discloses a kind of detection method of prohibited compound in complex matrix, realize the removal of solvent and low-boiling point matrix in liquid sample by pre-heating pretreatment;Using quadrupole mass spectrometer equipped with thermal desorption sampler and atmospheric ion source as detection instrument;1-5 μL drop of liquid sample to be measured is added on sample sheet, at the temperature of pre-heating 50-280 DEG C (preferably 160-180 DEG C) processing time 10 seconds to 10 minutes (preferably 4-6 minutes), realize the rapid volatilization of solvent and low-boiling point matrix in liquid sample;Finally, sample sheet is inserted into thermal desorption ionization cavity for gasification and ionization, start mass spectrum scanning, sample mass spectrum can be obtained;The result of the above detection is compared with the characteristic spectrum library of common toxicant of quadrupole mass spectrometer to determine whether prohibited compound is contained in beverage, electronic cigarette oil or not.The present application improves selectivity and identification accuracy.

Description

Technical Field

[0001] This invention belongs to the field of analytical chemistry instruments, specifically relating to a rapid and efficient method for detecting prohibited compounds in complex matrices. Background Technology

[0002] A quadrupole mass spectrometer (Ion Trap Mass Spectrometer) is an analytical instrument that uses an electromagnetic field to confine ions within a limited space. Ions are then allowed to escape individually or in batches from the ion trap by changing the electric field parameters, allowing for mass analysis. Working principle: The ion trap uses a radio frequency voltage applied to a ring electrode to cause ions to oscillate in three-dimensional space. By gradually increasing the radio frequency voltage, ions are forced into unstable regions and expelled through a small aperture, thus obtaining a mass spectrum. Structural composition: A typical ion trap consists of a ring electrode and two end cap electrodes, which can form a three-dimensional ion trap. A linear ion trap (LIT) is a type of ion trap where ions are focused along a line, increasing ion storage capacity and improving sensitivity. Advantages and features: High sensitivity: Ion traps can detect ions at very low abundance. Multistage mass spectrometry: It can perform MSn (multistage mass spectrometry) analysis, aiding in the structural identification of complex samples. Ease of operation: Compared to other types of mass spectrometers, quadrupole mass spectrometers are simple to operate and maintain. Cost-effectiveness: Compared to other types of mass spectrometers, quadrupole mass spectrometry offers a better cost-effectiveness ratio. Quadrupole mass spectrometry is a powerful and easy-to-operate analytical tool with significant applications in multiple fields.

[0003] Thermal desorption sampler is an essential component in multifunctional ion mobility spectrometry (IMS) rapid detection instruments. Its performance directly determines the injection efficiency and the overall performance of the IMS spectrometry. Existing IMS thermal desorption samplers use heating rods for temperature control, operating in a constant-temperature mode. Heating time varies depending on the heating rod power, currently ranging from 10-30 minutes. This method is relatively slow and consumes a significant amount of energy. Traditional heating rod temperature control offers the advantage of good temperature stability (CN201220715903), but its disadvantages include the inability to simultaneously achieve thermal desorption of low-boiling-point compounds at low temperatures and high-boiling-point compounds at high temperatures; it cannot simultaneously achieve thermal desorption of both low- and high-boiling-point targets. Infrared lamp heating offers the advantage of rapid heating (CN201210563261), but its disadvantage is that it is limited by lamp life and cannot operate for extended periods.

[0004] Current thermal desorption methods suffer from several drawbacks. During heating, a large number of low- and medium-boiling-point compounds are present, which dilute the target compound and affect its ionization efficiency, thus reducing sensitivity. Furthermore, due to the limited storage capacity of the ion trap, the large number of low- and medium-boiling-point compound ions entering the ion trap cavity makes it difficult to effectively store the target compound due to the Coulomb effect. This also affects the resolution of the quadrupole mass spectrometer, resulting in a weakening of qualitative analysis capabilities. Summary of the Invention

[0005] The purpose of this invention is to provide a rapid and efficient method for detecting prohibited compounds in complex matrices. By utilizing a preheating separation pretreatment technique, highly selective detection of high-boiling-point samples is achieved, avoiding interference from medium- and low-boiling-point compounds in the detection of target compounds.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A rapid and efficient method for detecting prohibited compounds in complex matrices.

[0008] Preheating pretreatment technology enables rapid and efficient pretreatment of solvents and low-boiling-point matrices in liquid samples, including pretreatment of e-liquid and beverage samples.

[0009] A quadrupole mass spectrometer equipped with a thermal desorption sampler and an atmospheric pressure ion source was used as the detection instrument.

[0010] Add 1-5 μL of e-liquid or beverage containing high-boiling-point drugs or medicines onto the sample slide and place it on a preheating module with 1 to 20 (preferably 8) preheating stations. By adjusting the preheating temperature and time, the solvent and low-boiling-point matrix are rapidly evaporated. Finally, insert the sample slide into the thermal desorption ionization chamber for vaporization and ionization, start the mass spectrometry scan, and obtain the sample mass spectrum.

[0011] The results of the above tests were compared with the quadrupole mass spectrometry database of common toxic substances to determine whether beverages and e-cigarette liquids contained prohibited compounds.

[0012] The specific analysis steps are as follows:

[0013] 1) Establishment of a library of characteristic spectra of common prohibited compounds:

[0014] a. The establishment of a database of prohibited compound standards was carried out using an ion detection instrument equipped with an atmospheric pressure ion source. Common prohibited compound standards were diluted with methanol to prepare three or more standard solutions with concentrations of 0.1-1 μg / mL. The standard solutions were then vaporized and ionized in a thermal desorption atmospheric pressure ion source, and detected separately using an ion detector in both parent ion and daughter ion modes. The spectra of different prohibited compounds and the peak positions of the parent and daughter ions were recorded and entered into the database as a basis for judging whether there are toxic substances.

[0015] b. Establishment of a simulated sample database containing prohibited compounds: Take e-cigarette oil or beverage samples, and add one of the common prohibited compound standards with a final concentration of 0.1-1 μg / mL to each sample to obtain a target sample solution. Use a micro-sampler to extract 0.1-200 μL (preferably 5 μL) of the target sample solution and place it on a sample slide. Place the slide on a preheating module with 1 to 20 (preferably 8) preheating stations at a temperature of 50-180℃ (preferably 150℃) for evaporation until no obvious droplets remain. Finally, place the sample slide in the thermal desorption ionization source of a quadrupole mass spectrometer for vaporization, ionization, and detection to obtain information on the parent ion and daughter ion.

[0016] Finally, a characteristic spectral library of prohibited compounds in simulated samples was established, including the characteristic ion peak information of the parent ion and daughter ion corresponding to each toxic substance;

[0017] 2) Analysis of the actual sample to be tested: Using a micro-sampler, extract 0.5-200 μL (preferably 5 μL) of the actual sample solution to be tested and place it on a sample slide. Place the slide on a preheating module with 1 to 20 (preferably 8) preheating stations at a temperature of 50-180℃ (preferably 150℃) for evaporation until no obvious droplets remain. Finally, place the sample slide in the thermal desorption ionization source of a quadrupole mass spectrometer for vaporization, ionization, and detection to obtain information on the parent ion and daughter ions. Compare this information with the sample database containing prohibited compounds from step 1) to find if there is a corresponding parent ion peak recorded in the prohibited compound characteristic spectrum library. If it corresponds to a parent ion peak in the database, the parent ion is screened and subjected to collisional dissociation mode detection to obtain its daughter ion information. Then, the daughter ions are compared. If the daughter ion corresponds to the database, the prohibited compound information is given. If no prohibited compound corresponding to the parent ion in the database is detected, the detection is completed, and a message indicating that no prohibited compound information was found in the database is given.

[0018] The prohibited compounds include one or more of the following seven categories: opioids, cannabis, cocaine, amphetamines, hallucinogens, sedatives, and synthetic cannabinoids.

[0019] Specifically, these include: opium, morphine, heroin, methamphetamine (ice), ecstasy, benzodiazepines, ADB-FUBINACA, 5F-MDMB-PICA, and AMB-FUBINACA.

[0020] The sample sheet is one or more of aluminum foil, copper foil, and gold foil.

[0021] The samples consist of one or more types of e-cigarette liquids and beverages.

[0022] Quadrupole mass spectrometry can be either a discontinuous injection quadrupole mass spectrometer equipped with a thermal desorption-atmospheric pressure ion source or a continuous injection quadrupole mass spectrometer.

[0023] This invention improves selectivity and recognition accuracy. Attached Figure Description

[0024] Figure 1 Mass spectrometry of direct detection of synthetic cannabinoids in e-cigarette liquid;

[0025] Figure 2 Mass spectra of synthesized cannabinoids obtained using preheating analysis technology. Detailed Implementation

[0026] A rapid and efficient method for detecting prohibited compounds in complex matrices utilizes a preheating pretreatment technique to achieve rapid and efficient pretreatment of solvents and low-boiling-point matrices in liquid samples, including pretreatment of e-liquid and beverage samples.

[0027] A quadrupole mass spectrometer equipped with a thermal desorption sampler and an atmospheric pressure ion source was used as the detection instrument.

[0028] Take 3 μL of e-cigarette oil containing cannabinoids and drop it onto the sample sheet. Place it on a preheating module with 1 to 20 (preferably 8) preheating stations. By adjusting the preheating temperature and time, the solvent and low-boiling-point matrix can be rapidly volatilized. Finally, insert the sample sheet into the thermal desorption ionization chamber for vaporization and ionization. Start the mass spectrometry scan to obtain the sample mass spectrum.

[0029] The results of the above tests were compared with the quadrupole mass spectrometry database of common toxic substances to determine whether beverages and e-cigarette liquids contained prohibited compounds.

[0030] The specific analysis steps are as follows:

[0031] 1) Establishment of a library of characteristic spectra of common prohibited compounds:

[0032] a. The establishment of a database of prohibited compound standards was carried out using an ion detection instrument equipped with an atmospheric pressure ion source. Common prohibited compound cannabinoid standards were diluted with methanol to prepare standard solutions with concentrations of 0.1, 0.3, 0.5, 0.6, 0.8, and 1 μg / mL. The standard solutions were placed in a thermal desorption atmospheric pressure ion source for vaporization and ionization, and then the target ions were detected using an ion-type detector. The spectral information of different prohibited compounds was recorded and entered into the database as a basis for judging whether there are toxic substances.

[0033] b. Establishment of a simulated sample database containing prohibited compounds: Take e-cigarette oil samples and add 0.1 μg / mL of common prohibited compound cannabinoid standards to each sample to obtain target sample solutions. Use a microsampler to extract 5 μL of the target sample solution and place it on a sample slide. Place the slide at 150℃ for 6 minutes to evaporate until no obvious droplets remain. Finally, place the sample slide in the thermal desorption / ionization source of a quadrupole mass spectrometer for vaporization, ionization, and detection to obtain the target ion information of the prohibited compound standards corresponding to step a.

[0034] Finally, a characteristic spectral library of prohibited compounds in simulated samples was established, including the characteristic ion peak information of parent and daughter ions corresponding to cannabinoids;

[0035] 2) Analysis of the actual sample to be tested: Using a micro-sampler, 5 μL of the actual sample solution of the e-cigarette oil to be tested was extracted and placed on a sample sheet. It was then placed at 150℃ for 6 minutes to evaporate until no obvious droplets remained. Finally, the sample sheet was placed in the thermal desorption / ionization source of a quadrupole mass spectrometer for vaporization, ionization, and detection to obtain information on the parent and daughter ions. The sample sheet was then compared with the database of samples containing prohibited compounds from step 1) to find if there was a corresponding target ion peak recorded in the prohibited compound characteristic spectrum library. If it corresponded to a certain ion peak in the database, the prohibited compound information was given; if no corresponding ion peak was found in the database, it indicated that the sample did not contain the corresponding prohibited compound information in the database. The sample sheet was aluminum foil.

[0036] Quadrupole mass spectrometry can be either a discontinuous injection quadrupole mass spectrometer equipped with a thermal desorption-atmospheric pressure ion source or a continuous injection quadrupole mass spectrometer.

Claims

1. A method for detecting prohibited compounds in complex matrices, characterized in that: Solvents and low-boiling-point matrices in liquid samples can be removed by preheating pretreatment; A quadrupole mass spectrometer equipped with a thermal desorption sampler and an atmospheric pressure ion source was used as the detection instrument. Take 1-5 μL of the liquid sample to be tested and add it to the sample plate; The sample is preheated at a temperature of 50℃-280℃ (preferably 160-180℃) for 10 seconds to 10 minutes (preferably 4-6 minutes) to achieve rapid evaporation of solvent and low-boiling-point matrix in the liquid sample; finally, the sample is inserted into the thermal desorption ionization chamber for vaporization and ionization, and mass spectrometry scanning is started to obtain the sample mass spectrum. The results of the above tests were compared with the quadrupole mass spectrometry database of common toxic substances to determine whether beverages and e-cigarette liquids contained prohibited compounds.

2. The method according to claim 1, characterized in that: The specific analysis steps are as follows: 1) Establishment of a library of characteristic spectra of common prohibited compounds: a. The establishment of a database of prohibited compound standards involves using an ion detection instrument equipped with a thermal desorption sampler and an atmospheric pressure ion source; common prohibited compound standards are diluted with methanol to prepare three or more standard solutions with concentrations of 0.1-1 μg / mL; the standard solutions are placed in a thermal desorption atmospheric pressure ion source for vaporization and ionization, and then the target ions are detected using an ion detector. The spectral information of different prohibited compounds is recorded and entered into the database as a basis for judging whether there are toxic substances. b. Establishment of a simulated sample database containing prohibited compounds: Take a liquid sample and add one of the common prohibited compound standards with a final concentration of 0.1-1 μg / mL to it to obtain a target sample solution; use a micro-sampler to extract 0.1-200 μL (preferably 3-5 μL) of the target sample solution and place it on a sample slide, and place it at a temperature of 50-280℃ (preferably 160-180℃) for evaporation for 10 seconds to 10 minutes (preferably 4-6 minutes) until no droplets remain; finally, place the sample slide in the thermal desorption ionization source of a quadrupole mass spectrometer for vaporization, ionization, and detection to obtain the target ion information of the prohibited compound standard corresponding to step a); Finally, a characteristic spectral library of prohibited compounds in simulated samples was established, including the characteristic ion peak information of the target ions corresponding to each poison. 2) Analysis of the actual sample to be tested: Using a micro-sampler, extract 0.5-200 μL (preferably 3-5 μL) of the actual sample solution to be tested and place it on a sample slide. Place it at a temperature of 50-280℃ (preferably 160℃) for evaporation of the liquid for 10 seconds to 10 minutes (preferably 4-6 minutes) until no droplets remain. Finally, place the sample slide in the thermal desorption ionization source of a quadrupole mass spectrometer for vaporization, ionization, and detection to obtain ion information. Compare the sample with the database of samples containing prohibited compounds from step 1) to find if there is a corresponding target ion peak recorded in the prohibited compound characteristic spectrum library: if it corresponds to a certain ion peak in the database, the prohibited compound information is given; if there is no corresponding ion peak in the database, it means that it does not contain the corresponding prohibited compound information in the database.

3. The method according to claim 1 or 2, characterized in that: The prohibited compounds include one or more of the following seven categories: opioids, cannabis, cocaine, amphetamines, hallucinogens, sedatives, and synthetic cannabinoids. Specifically, it includes one or more of the following: opium, morphine, heroin, methamphetamine (ice), ecstasy, benzodiazepines, ADB-FUBINACA, 5F-MDMB-PICA, and AMB-FUBINACA.

4. The method according to claim 1 or 2, characterized in that: The sample sheet is one or more of aluminum foil, copper foil, and gold foil.

5. The method according to claim 1 or 2, characterized in that: The samples consist of one or more types of e-cigarette liquids and beverages.

6. The method according to claim 1, characterized in that: The quadrupole mass spectrometer is equipped with a thermal desorption-atmospheric pressure ion source.

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