On-site rapid detection method for drugs in saliva

Abstract

The invention discloses an on-site rapid detection method for drugs in saliva. According to the method, a micro ion trap mass spectrometer equipped with a thermal desorption sample injector, an atmospheric pressure photochemical ionization source and a continuous atmospheric pressure interface is used as a detection instrument, the drugs in the saliva are extracted by using an organic solvent, rapid and high-sensitivity detection of the drugs in the saliva is realized, the time of the whole detection process is less than 1 min, the detection limit is less than 1 ng / ml, and the detection accuracy is high. The national standard detection requirements of drugs in saliva are met. The method comprises the following operation processes: taking 200 [mu] l of saliva for an obtained saliva sample, adding 200 [mu] l of an organic solvent into the saliva, centrifuging for 30 s, taking 1-10 [mu] l of supernatant liquid by using a sample injection needle, dripping the supernatant liquid on sampling test paper, after the solvent is volatilized at room temperature, inserting the sampling test paper into a thermal desorption sample injector, starting mass spectrum scanning, and obtaining a sample mass spectrum within 1 s.

Description

Technical Field

[0001] The present invention relates to a method for rapid on-site detection of drugs in saliva. This method uses a micro ion trap mass spectrometer equipped with a thermal desorption injector, an atmospheric pressure photoionization source, and a continuous atmospheric pressure interface as the detection instrument, and uses an organic solvent to extract drugs in saliva, achieving rapid and highly sensitive detection of drugs in saliva. The entire detection process takes less than 1 minute, and the detection limit is less than 1 ng / ml, meeting the national standard requirements for drug detection in saliva. Background Art

[0002] Drug driving refers to the act of driving a vehicle after taking or injecting opium, heroin, methamphetamine (ice), morphine, marijuana, and other narcotic drugs and psychotropic substances that are regulated by the state and can cause addiction, and the drug content in the blood and saliva reaches or exceeds the specified threshold. Drug driving will seriously affect the driving ability of the driver. The reaction ability of the driver after drug driving is about 21% slower than that of a normal driver. Due to the impact of drugs on vision, cognition, and motor ability, it seriously threatens road safety. Saliva is a colorless, transparent, and easily collectible body fluid. 99.5% of it is water, with less protein and lipid content and fewer interfering substances, and is increasingly being used in judicial and clinical detections. The rapid on-site detection of drugs in saliva is expected to provide strong support for drug driving.

[0003] Currently, the methods for drug detection in saliva mainly include immunoassay, surface-enhanced Raman spectroscopy, and colorimetry, etc. Most commercial drug detection instruments for saliva use immunoassay for detection, but in related detections, it is found that there is a problem of the same degree of cross-reaction for drugs with similar structures, and the detection of a large number of new synthetic drugs cannot be detected. Raman spectroscopy is a method of spectral analysis based on molecular vibration and can provide highly specific fingerprint spectra of molecules. Wu Yuanzhao et al. realized a rapid detection analyzer capable of simultaneously detecting 4 drugs in saliva through surface plasmon resonance; however, Raman spectroscopy still has the problems of being easily interfered by complex matrices and being unable to effectively detect compounds with similar structures. Mass spectrometry is the gold standard for quantitative detection, and the standard qualitative and quantitative method for drug driving is to detect through chromatograph-mass spectrometry methods. In order to perform mass spectrometry analysis outside the laboratory, miniaturized mass spectrometry technology has been continuously developed, with great potential for on-site rapid detection. In order to achieve rapid, highly sensitive on-site detection of drugs in saliva, the present invention uses a micro ion trap mass spectrometer equipped with a thermal desorption injector, an atmospheric pressure photoionization source, and a continuous atmospheric pressure interface as the detection instrument, and uses an organic solvent to extract drugs in saliva, achieving rapid and highly sensitive detection of drugs in saliva. The entire detection process takes less than 1 minute, and the detection limit is less than 1 ng / ml, meeting the national standard requirements for drug detection in saliva. Summary of the Invention

[0004] The present invention discloses a method for rapid on-site detection of drugs in saliva. This method uses a micro ion trap mass spectrometer equipped with a thermal desorption injector, an atmospheric pressure photoionization source, and a continuous atmospheric pressure interface as the detection instrument. Organic solvents are used to extract drugs in saliva, enabling rapid and highly sensitive detection of drugs in saliva. The entire detection process takes less than 1 minute, and the detection limit is less than 1 ng / ml, meeting the national standard requirements for drug detection in saliva.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] The present invention uses a micro ion trap mass spectrometer equipped with a thermal desorption injector, an atmospheric pressure photoionization source, and a continuous atmospheric pressure interface as the detection instrument. Organic solvents are used to extract drugs in saliva. After centrifugation and stratification, the upper clear liquid is taken with a sampling needle and spotted on a sampling test paper. After the solvent volatilizes at room temperature, the sampling test paper is inserted into the thermal desorption injector. The carrier gas carrying the photo-chemical auxiliary reagent sweeps the sample into the ionization region and enters the ion trap mass analyzer through the continuous atmospheric pressure interface for analysis. The sample mass spectrum is obtained within 1 s after starting the mass spectrometry scan. The result of the above detection is compared with the drug detection spectrum library of the ion trap mass spectrometry to determine whether there are drugs in the saliva.

[0007] The specific analysis steps involved in the present invention are as follows:

[0008] 1) Establishment of drug detection spectrum library: Using organic solvents, a standard solution of one or more drug standard solutions with a concentration of 100 μg / ml is serially diluted into a standard solution with a concentration of 0.1 - 1 μg / ml. 1 - 10 μl of the diluted standard solution is taken with a sampling needle and spotted on a sampling test paper. After the solvent volatilizes at room temperature, the sampling test paper is inserted into the thermal desorption injector. The carrier gas carrying the photo-chemical auxiliary reagent sweeps the sample into the ionization region and enters the ion trap mass analyzer through the continuous atmospheric pressure interface for analysis. The mass spectra of different drugs are obtained by starting the mass spectrometry scan, and the corresponding mass spectral peaks of the above drugs are obtained to establish a drug detection spectrum library;

[0009] 2) Analysis of saliva samples: For the obtained saliva samples, 100 - 500 μl of saliva is taken, an equal amount of organic solvent is added to the saliva, and centrifuged for 30 - 120 s. 1 - 10 μl of the upper clear liquid is taken with a sampling needle and spotted on a sampling test paper. After the solvent volatilizes at room temperature, the sampling test paper is inserted into the thermal desorption injector. The carrier gas carrying the photo-chemical auxiliary reagent sweeps the sample into the ionization region and enters the ion trap mass analyzer through the continuous atmospheric pressure interface for analysis. The sample mass spectrum is obtained within 1 s after starting the mass spectrometry scan. The obtained mass spectral peaks are compared with the drug detection spectrum library in step 1) to determine whether there are drugs in the saliva.

[0010] The types of organic solvents can be one or more of methanol, acetonitrile, ethyl acetate, methyl tert-butyl ether, cyclohexane, etc.

[0011] The type of carrier gas for the injector can be one or more of stable gases such as dry air, nitrogen, helium, or argon, and the flow rate of the carrier gas is adjustable.

[0012] The photochemical auxiliary reagent is one or more of reagents such as acetone, dichloromethane, and toluene.

[0013] The temperature of the thermal desorption injector is 160 - 200 °C.

[0014] The continuous atmospheric pressure interface is a capillary tube, and the material is one of peek, quartz, and stainless steel.

[0015] The organic solvent used to extract drugs from saliva is preferably ethyl acetate.

[0016] The carrier gas is air, and the flow rate of the carrier gas is preferably 100 ml / min.

[0017] The photochemical auxiliary reagent is preferably acetone.

[0018] The thermal desorption temperature is preferably 180 °C.

[0019] The continuous atmospheric pressure interface is preferably a stainless steel capillary tube.

[0020] The advantages of the present invention are as follows:

[0021] 1. The outstanding advantage of the present invention is that the micro - ion trap mass spectrometer equipped with a thermal desorption injector, an atmospheric pressure photoionization source, and a continuous atmospheric pressure interface has high sensitivity, small volume, and simple operation, and is suitable for on - site rapid detection.

[0022] 2. In the present invention, an organic solvent is used to rapidly extract drugs from saliva, and the pretreatment is rapid and efficient, and the entire analysis process does not exceed 1 minute.

[0023] 3. The drug detection spectral library established by the present invention not only covers common drugs but also new synthetic drugs, and has a wide detection range. Description of the Drawings

[0024] The following further describes the present invention in detail with reference to the drawings and embodiments:

[0025] Figure 1 It is a micro - ion trap mass spectrometer equipped with a thermal desorption injector, an atmospheric pressure photoionization source, and a continuous atmospheric pressure interface, where 1 is a sampling pump, 2 is a reagent bottle containing auxiliary reagents, 3 is an electric heating block in the thermal desorption injector, 4 is a sampling test paper, 5 is a vacuum ultraviolet lamp, 6 is an atmospheric pressure interface, 7 is an ion - transfer hexapole, 8 is the first - stage vacuum chamber, 9 is an aperture electrode, 10 is a focusing electrode, 11 is an ion trap mass analyzer, 12 is a detector, and 13 is the second - stage vacuum chamber;

[0026] Figure 2 It is the mass spectrum detected when the injection volume of ketamine in saliva is 100 ng / ml and the injection volume is 1 μL. Specific implementation mode

[0027] Example 1

[0028] The present invention uses a micro ion trap mass spectrometer equipped with a thermal desorption injector, an atmospheric pressure photoionization source, and a continuous atmospheric pressure interface as the detection instrument.

[0029] As Figure 1 shown: A reagent bottle with auxiliary reagents and an open upper end is placed in a sealed container; a carrier gas inlet and a reagent molecule outlet are respectively arranged on the sealed container on the left and right opposite sides of the reagent bottle; the carrier gas inlet is connected to a clean air source through a pipeline via a sampling pump, and the reagent molecule outlet is connected to the carrier gas inlet of the thermal desorption injector through a pipeline.

[0030] The atmospheric pressure photoionization source includes a sealed container, above which a vacuum ultraviolet lamp is arranged, and the light emitted by the vacuum ultraviolet lamp irradiates inside the sealed container. An inlet and an outlet are respectively arranged on the left and right side walls of the sealed container. The inlet is communicated with the sample outlet of the thermal desorption injector, and the outlet is communicated with the inlet of the micro ion trap mass spectrometer through a continuous atmospheric pressure interface.

[0031] An ion transmission hexapole 7 is arranged in the first-stage vacuum chamber 8, and an inlet is arranged on its left side wall. The right side wall of the first-stage vacuum chamber 8 and the left side wall of the second-stage vacuum chamber 13 share a common wall; an aperture electrode 9 is arranged on their common wall. A focusing electrode 10, an ion trap mass analyzer 11, and a detector 12 are arranged in the second-stage vacuum chamber 13. After ions enter the first-stage vacuum chamber 8, they sequentially pass through the ion transmission hexapole 7, the aperture electrode 9, the focusing electrode 10, and the ion trap mass analyzer 11, and are detected by the detector 12.

[0032] Extract the drugs in saliva with an organic solvent. After centrifugation and layering, use a sampling needle to take the upper clear liquid and spot it on the sampling test paper. After the solvent volatilizes at room temperature, insert the sampling test paper into the thermal desorption injector. The carrier gas carrying the photo-chemical auxiliary reagent blows the sample into the ionization region and enters the ion trap mass analyzer through the continuous atmospheric pressure interface for analysis. The sample mass spectrum is obtained within 1 s after starting the mass spectrometry scan. The results of the above detection are compared with the drug detection spectrum library of the ion trap mass spectrometry to determine whether there are drugs in saliva.

[0033] The specific analysis steps involved in the present invention are:

[0034] 1) Establishment of drug detection spectral library: Using methanol, 27 kinds of drug standard solutions with a concentration of 100 μg / ml were serially diluted into standard solutions with a concentration of 1 μg / ml. 1 μl of the diluted standard solution was taken with a syringe and spotted on the sampling test paper. After the solvent evaporated at room temperature, the sampling test paper was inserted into the thermal desorption injector. The carrier gas air carrying the photochemical auxiliary reagent acetone purged the sample into the ionization region and entered the ion trap mass analyzer through the continuous atmospheric pressure interface for analysis. The mass spectrometry scan was started to obtain the mass spectra of different drugs, and the corresponding mass spectral peaks of the above drugs were obtained to establish a drug detection spectral library. The drugs and their corresponding mass-to-charge ratios (m / z) in the drug detection spectral library are shown in Table 1;

[0035]

[0036]

[0037] Table 1 Drug information in the drug detection spectral library

[0038] 2) Analysis of saliva samples: For the obtained saliva samples, 200 μl of saliva was taken, an equal volume of ethyl acetate was added to the saliva, and centrifuged (rotation speed 600 rpm) for 45 s. 1 μl of the upper clear liquid was taken with a syringe and spotted on the sampling test paper. After the solvent evaporated at room temperature, the sampling test paper was inserted into the thermal desorption injector. The carrier gas carrying the photochemical auxiliary reagent purged the sample into the ionization region and entered the ion trap mass analyzer through the continuous atmospheric pressure interface for analysis. The mass spectrum of the sample was obtained within 1 s after starting the mass spectrometry scan. By comparing the obtained mass spectral peaks with the drug detection spectral library in step 1), it was further determined whether the saliva contained drugs.

[0039] The type of carrier gas for the injector is dry air and the flow rate of the carrier gas is 100 ml / min;

[0040] The photochemical auxiliary reagent is acetone.

[0041] The temperature of the thermal desorption injector is 160 °C.

[0042] The continuous atmospheric pressure interface is a stainless steel metal capillary.

[0043] Example 2

[0044] 100 μL of 1 μg / mL ketamine was added to 900 μL of saliva taken from volunteers. After vortexing for three minutes, a spiked sample of 100 ng / mL was obtained. 200 μL of saliva was taken, an equal volume of ethyl acetate was added to the saliva, and it was centrifuged for 45 s. 1 μL of the supernatant was taken with a sampling syringe and spotted on a sampling test paper. After the solvent had evaporated at room temperature, the sampling test paper was inserted into a thermal desorption injector. The carrier gas carrying the photochemical auxiliary reagent purged the sample into the ionization region and entered the ion trap mass analyzer through a continuous atmospheric pressure interface for analysis. The mass spectrum of the sample was obtained within 1 s after starting the mass spectrometry scan. By comparing the obtained mass spectrometry peaks with the drug detection spectral library in step 1) of Example 1, it was further determined that ketamine was contained in the saliva.

[0045] Figure 2 Mass spectrometry diagram detected when the injection volume of 100 ng / mL ketamine in saliva was 1 μL.

Claims

1. A rapid on-site detection method for drugs in saliva, characterized in that: A micro ion trap mass spectrometer equipped with a thermal desorption injector, an atmospheric pressure photoionization source, and a continuous atmospheric pressure interface is used as the detection instrument. Organic solvents are used to extract drugs in saliva. After centrifugation and layering, the upper clear liquid is taken with a sampling syringe and spotted on a sampling test paper. After the solvent evaporates at room temperature, the sampling test paper is inserted into the thermal desorption injector. The carrier gas carrying the photo-chemical auxiliary reagent sweeps the sample into the ionization region and enters the ion trap mass analyzer through the continuous atmospheric pressure interface for analysis. A sample mass spectrum is obtained within 1 s after starting the mass spectrometry scan; The result of the above detection is compared with the drug detection spectrum library of the ion trap mass spectrometer to determine whether there are drugs in the saliva.

2. The method according to claim 1, characterized in that: The specific analysis steps are as follows: 1) Establishment of the drug detection spectrum library: Using organic solvents, a drug standard solution of 100 ug / ml of one or more than two kinds is gradually diluted into a standard solution of 0.1 - 1 ug / ml. 1 - 10 ul of the diluted standard solution is taken with a sampling syringe and spotted on a sampling test paper. After the solvent evaporates at room temperature, the sampling test paper is inserted into the thermal desorption injector. The carrier gas carrying the photo-chemical auxiliary reagent sweeps the sample into the ionization region and enters the ion trap mass analyzer through the continuous atmospheric pressure interface for analysis. The mass spectrometry scan is started to obtain the mass spectra of different drugs, and the corresponding mass spectral peaks of the above drugs are obtained to establish a drug detection spectrum library; 2) Analysis of saliva samples: For the obtained saliva samples, 100 - 500 ul of saliva is taken, an equal volume of organic solvent is added to the saliva, and centrifuged for 30 - 120 s. 1 - 10 ul of the upper clear liquid is taken with a sampling syringe and spotted on a sampling test paper. After the solvent evaporates at room temperature, the sampling test paper is inserted into the thermal desorption injector. The carrier gas carrying the photo-chemical auxiliary reagent sweeps the sample into the ionization region and enters the ion trap mass analyzer through the continuous atmospheric pressure interface for analysis. A sample mass spectrum is obtained within 1 s after starting the mass spectrometry scan. According to the obtained mass spectral peaks, a comparison is made with the drug detection spectrum library in step 1) to further determine whether there are drugs in the saliva.

3. The method according to claim 1, characterized in that: The types of organic solvents can be one or more than two of methanol, acetonitrile, ethyl acetate, methyl tert-butyl ether, cyclohexane, etc.

4. The method according to claim 1, characterized in that: The types of carrier gas for the injector can be one or more than two of stable gases such as dry air, nitrogen, helium, or argon, and the flow rate of the carrier gas is adjustable; The photo-chemical auxiliary reagent is one or more than two of reagents such as acetone, dichloromethane, toluene, etc.

5. The method according to claim 1, characterized in that: The temperature of the thermal desorption injector is 160 - 200 °C.

6. The method according to claim 1, characterized in that: The continuous atmospheric pressure interface is a capillary tube, and the material is one or more than two of peek, quartz, and stainless steel.

7. The method according to claim 1, characterized in that: The organic solvent used to extract drugs in saliva is preferably ethyl acetate.

8. The method according to claim 1, characterized in that: The carrier gas is air, and the flow rate of the carrier gas is preferably 100 ml / min; The photochemical auxiliary reagent is preferably acetone.

9. The method according to claim 1 or 5, characterized in that: The thermal desorption temperature is preferably 180 °C.

10. The method according to claim 1, characterized in that: The continuous atmospheric pressure interface is preferably a stainless steel capillary.

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