A method for detecting amphetamines in drugs based on anthracene-based probes

Abstract

The application provides a method for detecting amphetamine in drugs by using an anthryl probe, which comprises using an aldehyde group and a dicyano vinyl group as recognition groups, anthracene as a light-emitting center and benzothiadiazole as a pi bridge, and can be obtained through a Suzuki coupling and a Grignard reagent condensation reaction. The anthryl probe with the aldehyde group as the recognition group changes from orange to yellow in fluorescence color before and after the addition of amphetamine. The anthryl probe with the dicyano vinyl group as the recognition group changes from dark red to yellow in fluorescence color before and after the addition of amphetamine. Both of the two probes present a ratio fluorescence signal. In order to facilitate the on-site practical detection application, the probe is loaded on a sponge substrate to make an analysis card. After the addition of an amphetamine solution, the fluorescence color changes from orange to green, and the colorimetric effect changes from orange to light yellow. The detection is not interfered by other common drugs, amine substances and the like. The application has the advantages of high sensitivity, high specificity, rapidness and visualization, and has a wide application prospect in on-site analysis of drugs.

Description

Technical Field

[0001] This invention belongs to the field of drug detection and provides a method for detecting amphetamine in drugs using an anthracene-based probe. This probe has a low detection limit, strong anti-interference capabilities, and a short reaction time, enabling low-cost, real-time fluorescence detection of amphetamine in drugs. Background Technology

[0002] Drugs harm people's health and can easily lead to other crimes. In actual manufacturing, trafficking and abuse scenarios, the complex and varied composition and form of drugs, as well as their strong camouflage, pose great challenges to on-site detection.

[0003] Amphetamine, a stimulant psychotropic drug, is highly addictive because it induces euphoria by inhibiting the release of dopamine inhibitors. Its smuggling and abuse are serious problems, and it has become a representative Class II synthetic drug. Achieving highly sensitive, rapid-response, and selective on-site detection is of great significance for strictly controlling its abuse, transportation, and sale, thereby effectively reducing crime.

[0004] Compared to other methods of on-site drug detection, such as chromatography-mass spectrometry, infrared spectroscopy, Raman spectroscopy, electrical analysis, and ion mobility spectrometry, optical sensing methods based on colorimetry and fluorescence can utilize the selective interaction between the designed recognition group and the target molecule to change its stacking state or chemical structure. The intensity of the resulting change in light signal is accumulated to output a detectable and visual signal. Due to its many excellent characteristics, such as intuitive results, adjustable structure, high specificity, fast response speed, and highly modular devices, it has become one of the important solutions for on-site drug detection.

[0005] This invention develops a method for detecting amphetamine in drugs based on anthracene probes. This method achieves highly specific and sensitive rapid on-site fluorescence detection of amphetamine by using a probe with anthracene as the fluorophore, benzothiadiazole as the π-bridge, and aldehyde or dicyanvinyl as the reaction site, in the form of a detection reagent or a sponge analysis card. Summary of the Invention

[0006] The purpose of this invention is to provide a method for detecting amphetamine in drugs based on anthracene-based probes. This method utilizes two anthracene-based probes, both capable of ratiometric fluorescence detection of amphetamine. The two anthracene-based probes use aldehyde and dicyanvinyl groups as recognition groups, respectively, with anthracene as the luminescent center and benzothiadiazole as the π-bridge. They are obtained through Suzuki coupling and Kneven-Gail condensation reactions. Specifically, the anthracene-based probe with the aldehyde group as the recognition group changes its fluorescence color from orange to yellow upon the addition of amphetamine; the anthracene-based probe with the dicyanvinyl group changes its fluorescence color from dark red to yellow upon the addition of amphetamine. Both probes exhibit ratiometric fluorescence signals. For ease of practical application in the field, the dicyanvinyl-anthrayl probe is loaded onto a sponge substrate to create an analytical card. Upon adding an amphetamine solution, the fluorescence color changes from orange to green, and the colorimetric effect changes from orange to pale yellow. The detection is unaffected by interference from other common drugs and amines. This invention offers advantages such as high sensitivity, high specificity, speed, and visualization, and has broad application prospects in on-site drug analysis.

[0007] The method for detecting amphetamine in drugs based on anthracene probes according to the present invention is carried out according to the following steps:

[0008] Preparation of detection reagents:

[0009] a. Weigh 2-anthraboric acid and 7-bromo-4-aldehyde benzo[C][1,2,5]thiadiazole in a molar ratio of 1:1, place them in a 100 mL three-necked flask, add 10 mL toluene, 5 mL pure water and 10 mL tert-butanol, and under nitrogen atmosphere protection, control the reaction temperature at 85 °C and stir. Then slowly add sodium carbonate and the catalyst tetra(triphenylphosphine)palladium, and react in the dark for 36 h.

[0010] b. After the reaction is complete, wash with dilute hydrochloric acid solution until neutral, extract with dichloromethane, dry with anhydrous magnesium sulfate, filter and evaporate to dryness to obtain crude aldehyde-anthrayl probe product, then recrystallize with methanol and purify by column chromatography to obtain orange solid, which is aldehyde-anthrayl probe.

[0011] c. Place the aldehyde-anthrayl probe obtained in step b and malononitrile in a 1:1 molar ratio into a 100 mL three-necked flask, add 1 mL of pyridine and 10 mL of toluene, and under nitrogen atmosphere protection, control the reaction temperature at 60 °C and stir, and react in the dark for 24 h.

[0012] d. After the reaction was complete, the sample was extracted with dichloromethane, dried with anhydrous magnesium sulfate, filtered and evaporated to dryness to obtain the crude product of dicyanvinyl-anthrayl probe. The crude product was then purified by recrystallization with methanol and column chromatography to obtain the red solid as dicyanvinyl-anthrayl probe.

[0013] e. Dissolve the aldehyde-anthrayl probe obtained in step b and the dicyandiamide-anthrayl probe obtained in step d in tetrahydrofuran, respectively. After ultrasonic dissolution, prepare aldehyde-anthrayl probe solution and dicyandiamide-anthrayl probe solution with a concentration of 0.01-1 mmol / L to obtain two detection reagents for identifying amphetamine.

[0014] Aldehyde-anthrayl probe for the detection of amphetamine:

[0015] f. Take 450 μL of the 0.05 mmol / L aldehyde-anthrayl probe solution obtained in step e into a test tube, and then add 50 μL of a 5 mmol / L amphetamine solution. After the reaction is complete, record the fluorescence spectrum and optical photograph under 365 nm ultraviolet light excitation conditions, and observe the signal changes of the fluorescence characteristic emission peaks before and after the reaction.

[0016] Detection of amphetamine using a dicyandiamide-anthrayl probe:

[0017] g. Take 450 μL of the 0.05 mmol / L dicyandiamide-anthrayl probe solution obtained in step e into a test tube, then add 50 μL of a 5 mmol / L amphetamine solution. After the reaction is complete, record the fluorescence spectrum and optical photograph under 365 nm ultraviolet light excitation conditions, and observe the signal changes of the fluorescence characteristic emission peaks before and after the reaction.

[0018] Alternatively, a polyurethane sponge can be immersed in a 0.1 mmol / L dicyandiamide-anthrayl probe solution. After complete immersion, the sponge is removed and dried in an oven at 40°C until the solvent is completely evaporated, resulting in a sponge analysis card loaded with the dicyandiamide-anthrayl probe. 20 μL of the amphetamine solution to be detected is then added to the sponge analysis card loaded with the dicyandiamide-anthrayl probe, and colorimetric and fluorescence changes are observed under sunlight and 365 nm illumination.

[0019] The present invention discloses a method for detecting amphetamine in drugs based on anthracene probes. The chemical names of the aldehyde-anthrayl probe and the dicyandiamide-anthrayl probe are 7-(anthrayl-2-yl)benzo[2,1-c][1,2,5]thiadiazacyclopentanyl-4-carboxaldehyde (abbreviated as aldehyde-anthrayl probe) and 2-{[7-(anthrayl-2-yl)benzo[2,1-c][1,2,5]thiadiazacyclopentanyl-4-yl]methylidene}malonitrile (abbreviated as dicyandiamide-anthrayl probe), respectively. These probes can be obtained through Suzuki coupling and Knauven-Gale condensation reactions. The corresponding chemical structural formulas (I) and (II) of the aldehyde-anthrayl probe and the dicyandiamide-anthrayl probe are as follows:

[0020]

[0021] This invention discloses a method for the fluorescent detection of amphetamine in drugs using an anthracene-based probe. In this method, anthracene-based probes with aldehyde and dicyanvinyl groups as response groups can achieve ratiometric fluorescence detection of amphetamine. The dicyanvinyl-anthrayl probe has a naked-eye detection limit of 60 μmol / L for amphetamine, with a detection linear range of 20-500 μmol / L. When a sponge analytical card loaded with the dicyanvinyl-anthrayl probe is used in simulated field detection applications, the fluorescence color changes from orange to green within 60 seconds of adding amphetamine, accompanied by a colorimetric change from orange to pale yellow. Other common drugs and amines do not significantly interfere with the detection of amphetamine. This invention has no special limitations in use; qualitative detection can be rapidly completed at room temperature without pretreatment of the analyte. It is simple to operate, economical and practical, with high specificity and sensitivity, and stable and reproducible results. These advantages make this invention easily applicable and widely promoted in the field of on-site point-of-care testing.

[0022] The anthracene-based probes respond to amphetamine with aldehyde and dicyanvinyl groups. In the presence of amphetamine, both probes exhibit significant ratiometric fluorescence changes: orange to yellow (aldehyde-anthrayl probe) and dark red to yellow (dicyanvinyl-anthrayl probe). When the probes are loaded onto a sponge substrate to form an analytical card, and an amphetamine solution is added, a significant fluorescence response change occurs within 60 seconds, simultaneously exhibiting a colorimetric phenomenon of orange turning pale yellow. This probe demonstrates excellent recognition ability for amphetamine, and amphetamine detection is unaffected by interference from other common drugs and amines. This invention provides a sound research foundation and an effective means of drug detection and procurement at the scene.

[0023] The present invention discloses a method for detecting amphetamine in drugs using an anthracene-based probe. The detection principle of this method is as follows: the amino group of the analyte amphetamine nucleophilically attacks the aldehyde group or dicyanvinyl double bond of the anthracene-based probe molecule, thereby undergoing an addition reaction. Then, an elimination reaction occurs to remove water or malononitrile to form a double bond. The change in the molecular structure of the probe to the product corresponds to the change in fluorescence color. Attached Figure Description

[0024] Figure 1 The detection efficacy of the aldehyde-anthrayl probe and the dicyandiamide-anthrayl probe for amphetamine in Example 1 of this invention is shown.

[0025] Figure 2 The detection effect of different concentrations of dicyandiamide-anthrayl probe molecules on amphetamine in Example 2 of the present invention;

[0026] Figure 3 This invention describes the fluorescence changes of dicyandiamide-anthrayl probe molecules before and after the reaction of a series of concentrations of amphetamine in Example 3 of the present invention, and their correlation with the concentration of amphetamine.

[0027] Figure 4 The detection effect of the dicyandiamide-anthrayl probe molecule in Example 4 of the present invention on amphetamine and other common amines;

[0028] Figure 5 The detection effect of the dicyandiamide-anthracite probe-sponge-based analytical card for amphetamine in Example 5 of this invention;

[0029] Figure 6 The image shows the response time of the dicyandiamide-anthracite probe-sponge-based analytical card to amphetamine in Example 6 of this invention.

[0030] Figure 7 The detection efficacy of the dicyandiamide-anthracite probe-sponge-based analytical card in Example 7 of this invention for amphetamine and other common drugs is shown. Detailed Implementation

[0031] The present invention will be further described below through specific embodiments, but the invention is not limited to these embodiments.

[0032] Example 1

[0033] Preparation of aldehyde-anthrayl probes:

[0034] a. Weigh 0.901 mmol and 0.200 g of 2-anthraboric acid and 0.900 mmol and 0.218 g of 7-bromo-4-aldehyde benzo[C][1,2,5]thiadiazole in a molar ratio of 1:1, place them in a 100 mL three-necked flask, add 10 mL of toluene, 5 mL of pure water and 10 mL of tert-butanol, and under a nitrogen atmosphere, control the reaction temperature at 85 °C and stir. Then slowly add 2.698 mmol and 0.286 g of sodium carbonate and 0.043 mmol and 0.050 g of tetra(triphenylphosphine)palladium catalyst, and react in the dark for 36 h.

[0035] b. After the reaction is complete, wash with dilute hydrochloric acid solution until neutral, extract with dichloromethane, dry with anhydrous magnesium sulfate, filter and evaporate to dryness to obtain crude aldehyde-anthrayl probe product, then recrystallize with methanol and purify by column chromatography to obtain orange solid, which is aldehyde-anthrayl probe.

[0036] Preparation of dicyandiamide-anthrayl probe:

[0037] c. Place the aldehyde-anthrayl probe obtained in step b and malononitrile in a 1:1 molar ratio into a 100 mL three-necked flask, add 1 mL of pyridine and 10 mL of toluene, and under nitrogen atmosphere protection, control the reaction temperature at 60 °C and stir, and react in the dark for 24 h.

[0038] d. After the reaction was complete, the sample was extracted with dichloromethane, dried with anhydrous magnesium sulfate, filtered and evaporated to dryness to obtain the crude product of dicyanvinyl-anthrayl probe. The crude product was then purified by recrystallization with methanol and column chromatography to obtain the red solid as dicyanvinyl-anthrayl probe.

[0039] Preparation of test reagents:

[0040] e. Dissolve the aldehyde-anthrayl probe obtained in step b and the dicyandiamide-anthrayl probe obtained in step d in tetrahydrofuran, respectively. After ultrasonic dissolution, prepare aldehyde-anthrayl probe solution and dicyandiamide-anthrayl probe solution with a concentration of 0.05-1 mmol / L to obtain two detection reagents for identifying amphetamine.

[0041] The detection efficacy of aldehyde-anthrayl probe molecules for amphetamine in tetrahydrofuran solvent:

[0042] f. Take 450 μL of the 0.05 mmol / L aldehyde-anthrayl probe solution obtained in step e into a test tube, then add 50 μL of a 5 mmol / L amphetamine solution. After the reaction is complete, select an excitation wavelength of 365 nm, record the fluorescence spectrum, and take a fluorescence image; the detection effect of the aldehyde-anthrayl probe molecule on amphetamine in tetrahydrofuran solvent is as follows. Figure 1 As shown, under 365nm ultraviolet light irradiation, the fluorescence color of the reagent changes from orange to yellow. In addition, when measured with a fluorescence spectrometer, the fluorescence characteristic peak shifts from 650nm to about 590nm when the excitation wavelength is selected as 365nm. The above phenomena show obvious fluorescence changes.

[0043] The detection efficacy of dicyandiamide-anthrayl probe molecules for amphetamine in tetrahydrofuran solvent:

[0044] g. Take 450 μL of the 0.05 mmol / L dicyandiamide-anthrayl probe solution obtained in step e into a test tube, then add 5 mmol / L amphetamine solution. After the reaction is complete, select an excitation wavelength of 365 nm, record the fluorescence spectrum, and take a fluorescence image; the detection effect of the dicyandiamide-anthrayl probe molecule on amphetamine in tetrahydrofuran solvent is as follows: Figure 1 As shown, under 365nm ultraviolet light irradiation, the fluorescence color of the reagent changes from red to yellow. In addition, when measured with a fluorescence spectrometer, the fluorescence characteristic peak shifts from 735nm to about 590nm when the excitation wavelength is selected as 365nm. The above phenomena show obvious fluorescence changes.

[0045] Example 2

[0046] The detection efficacy of different concentrations of dicyandiamide-anthrayl probe molecules for amphetamine:

[0047] Preparation of detection reagents: The dicyandiamide-anthrayl probe prepared in step d of Example 1 was dissolved in tetrahydrofuran solution to prepare dicyandiamide-anthrayl probe solutions with concentrations of 0.01, 0.05, 0.125, 0.25, 0.5, and 1 mmol / L, respectively. Then, 450 μL of the corresponding concentration of dicyandiamide-anthrayl probe solution was placed in a test tube to obtain the detection reagents.

[0048] Preparation of amphetamine standard solution: Prepare a 5 mmol / L amphetamine standard solution using tetrahydrofuran as the solvent;

[0049] Detection process: Add 50 μL of the amphetamine standard solution obtained in step b to the detection reagents with different probe concentrations obtained in step a. After the reaction is complete, select an excitation wavelength of 365 nm, record the fluorescence spectrum and take a fluorescence image.

[0050] Detection results: The detection results of tetrahydrofuran solutions of different concentrations of dicyandiamide-anthrayl probe molecules for amphetamine are as follows: Figure 2 As shown, under 365nm UV light irradiation, the fluorescence color of the reagents all turned yellow after the reaction; at probe concentrations of 0.01, 0.05, 0.125, 0.25, 0.5, and 1 mmol / L, the fluorescence changes before and after the reaction to detect amphetamine were all quite obvious, proving that the dicyandiamide-anthrayl probe is effective for the detection of amphetamine within this concentration range.

[0051] Example 3

[0052] Detection of a range of concentrations of amphetamine using a dicyandiamide-anthrayl probe:

[0053] Preparation of detection reagent: Dissolve the dicyandiamide-anthrayl probe prepared in step d of Example 1 in tetrahydrofuran solution to prepare a dicyandiamide-anthrayl probe solution with a concentration of 0.05 mmol / L. Take 450 μL into a test tube to obtain the detection reagent;

[0054] Preparation of amphetamine standard solutions: Amphetamine standard solutions with concentrations of 0.2, 0.4, 0.6, 0.8, 1.0, 1.5, 2.0, 3.0, 4.0, and 5.0 mmol / L were prepared using tetrahydrofuran as the solvent.

[0055] Detection process: Add 50 μL of the prepared amphetamine standard solution to the detection reagent. After the reaction is complete, select an excitation wavelength of 365 nm and measure the fluorescence spectrum. Use the ratio of the fluorescence intensity at the product characteristic peak of 590 nm to the probe characteristic peak of 735 nm to generate a calibration curve corresponding to the amphetamine content.

[0056] Detection results: such as Figure 3As shown, the ratio of the intensity of the product characteristic peak to the probe characteristic peak after the reaction of the dicyandiamide-anthrayl probe molecule in the tetrahydrofuran solvent system to detect amphetamine showed a good linear relationship with the concentration change of amphetamine in the range of 20-500 μmol / L. Therefore, this probe molecule can be used to quantitatively detect amphetamine molecules.

[0057] Example 4

[0058] Detection of amphetamine and its amine interfering substances using a dicyandiamide-anthrayl probe:

[0059] Preparation of detection reagent: Dissolve the dicyandiamide-anthrayl probe prepared in step d of Example 1 in tetrahydrofuran to prepare a dicyandiamide-anthrayl probe solution with a concentration of 0.05 mmol / L. Take 450 μL of the 0.05 mmol / L dicyandiamide-anthrayl probe tetrahydrofuran solution into a test tube to obtain the detection reagent.

[0060] Preparation of analyte solution: Using tetrahydrofuran as solvent, other common amines such as aniline, diphenylamine, triethylamine, dimethylaniline, sulfonamide, ammonia, L-glutamine, p-toluidine, and triethanolamine are used as interfering substances for the detection of amphetamine to prepare solutions with a corresponding concentration of 50 mmol / L.

[0061] Detection process: Add 50 μL of 50 mmol / L of other common amines or 5 mmol / L of amphetamine to the prepared detection reagent. After the reaction is complete, select an excitation wavelength of 365 nm and record the fluorescence spectrum and optical photograph.

[0062] Detection results: The detection results of the dicyandiamide-anthrayl probe for amphetamine and its amine interfering substances are as follows: Figure 4 As shown, the addition of amphetamine caused the color of the detection reagent to change from dark red to yellow, and the fluorescence characteristic peak shifted from 735 nm to about 590 nm. Other common amines did not significantly interfere with the detection, indicating that the dicyandiamide-anthrayl probe molecule has good selectivity for amphetamine.

[0063] Example 5

[0064] The detection effect of sponge-based supported dicyandiamide-anthrayl probe molecules on amphetamine methanol solution:

[0065] Preparation of dicyanvinyl-anthrayl probe composite sponge substrate: The dicyanvinyl-anthrayl probe prepared in step d of Example 1 was dissolved in tetrahydrofuran solution to prepare a dicyanvinyl-anthrayl probe solution with a concentration of 0.1 mmol / L. Then, a polyurethane sponge was immersed in the obtained dicyanvinyl-anthrayl probe solution. After complete immersion, it was taken out and dried in an oven at 40°C. After the solvent was completely evaporated, a sponge analysis card loaded with solid dicyanvinyl-anthrayl probe was obtained.

[0066] Preparation of amphetamine standard solution: Prepare a 5 mmol / L amphetamine standard solution using methanol as the solvent;

[0067] Detection process: 20 μL of the prepared amphetamine standard solution was added to the obtained sponge analysis card. After sufficient contact and reaction, the card was irradiated with white light and 365 nm ultraviolet light respectively. The colorimetric fluorescence effect was observed and photographed.

[0068] Detection results: The detection results of sponge-loaded dicyandiamide-anthrayl probe molecules for detecting amphetamine solution are as follows: Figure 5 As shown, its colorimetric effect changed from orange to pale yellow, and its fluorescence color changed from orange to green, with significant changes in both colorimetric and fluorescence.

[0069] Example 6

[0070] Response time of sponge-based supported dicyandiamide-anthrayl probe molecules to amphetamine

[0071] Preparation of dicyanvinyl-anthrayl probe composite sponge substrate: The dicyanvinyl-anthrayl probe prepared in step d of Example 1 was dissolved in tetrahydrofuran solution to prepare a dicyanvinyl-anthrayl probe solution with a concentration of 0.1 mmol / L. Then, a polyurethane sponge was immersed in the obtained dicyanvinyl-anthrayl probe solution. After complete immersion, it was taken out and dried in an oven at 40°C. After the solvent was completely evaporated, a sponge analysis card loaded with solid dicyanvinyl-anthrayl probe was obtained.

[0072] Preparation of amphetamine standard solution: Prepare a 5 mmol / L amphetamine standard solution using methanol as the solvent;

[0073] Detection process: 20 μL of the prepared amphetamine standard solution was added to the sponge analysis card and irradiated with 365 nm ultraviolet light. Fluorescence images were taken at 0, 30, 60, 120 and 180 s respectively.

[0074] Detection results: The response time of the sponge-based supported dicyandiamide-anthrayl probe molecule to 5 mmol / L amphetamine is as follows: Figure 6 As shown, its fluorescence color changes from orange to green within 60 seconds, and the response time is less than 60 seconds.

[0075] Example 7

[0076] Detection of amphetamine and other common drugs by loading dicyandiamide-anthrayl probes onto a sponge substrate.

[0077] Preparation of dicyanvinyl-anthrayl probe composite sponge substrate: The dicyanvinyl-anthrayl probe prepared in step d of Example 1 was dissolved in tetrahydrofuran solution to prepare a dicyanvinyl-anthrayl probe solution with a concentration of 0.1 mmol / L. Then, a polyurethane sponge was immersed in the obtained dicyanvinyl-anthrayl probe solution. After complete immersion, it was taken out and dried in an oven at 40°C. After the solvent was completely evaporated, a sponge analysis card loaded with solid dicyanvinyl-anthrayl probe was obtained.

[0078] Preparation of test solution: Using methanol as solvent, other common drugs such as methamphetamine, cocaine, morphine, barbiturates, ketamine, ecstasy, methamphetamine pills, opium, or marijuana are used as interfering agents for the detection of amphetamine. Prepare methanol solutions of interfering agents and methanol solutions of amphetamine with a corresponding concentration of 1 mg / mL.

[0079] Detection process: 20 μL of the obtained 1 mg / mL other common drugs and amphetamine were added to the prepared sponge analysis card. After the reaction was complete, the fluorescence changes were observed and fluorescence images were taken by irradiating with 365 nm ultraviolet light.

[0080] Detection results: The specific recognition of amphetamine by sponge-based supported dicyandiamide-anthrayl probe molecules is as follows: Figure 7 As shown, when 20 μL of a 1 mg / mL methanol solution of amphetamine was added to the sponge-based analytical card, the fluorescence color of the analytical card changed from orange to green within 60 seconds, while other drugs showed no obvious response. This indicates that the dicyandiamide-anthrayl probe molecule has good selectivity for amphetamine and has the potential for field application.

Claims

1. A method for detecting amphetamine in drugs based on anthracene probes, characterized in that, Follow these steps: Preparation of detection reagents: a. Weigh 0.901 mmol (0.200 g) of 2-anthraboric acid and 0.900 mmol (0.218 g) of 7-bromo-4-aldehyde benzo[C][1,2,5]thiadiazole in a molar ratio of 1:1, place them in a 100 mL three-necked flask, add 10 mL of toluene, 5 mL of pure water and 10 mL of tert-butanol, and stir under a nitrogen atmosphere while controlling the reaction temperature at 85 °C. Then slowly add 2.698 mmol (0.286 g) of sodium carbonate and 0.043 mmol (0.050 g) of tetra(triphenylphosphine)palladium catalyst, and react in the dark for 36 h. b. After the reaction is complete, wash with dilute hydrochloric acid solution until neutral, extract with dichloromethane, dry with anhydrous magnesium sulfate, filter and evaporate to dryness to obtain crude aldehyde-anthrayl probe product, then recrystallize with methanol and purify by column chromatography to obtain orange solid, which is aldehyde-anthrayl probe. c. Place the aldehyde-anthrayl probe obtained in step b and malononitrile in a molar ratio of 1:1 into a 100 mL three-necked flask, add 1 mL of pyridine and 10 mL of toluene, and under nitrogen atmosphere protection, control the reaction temperature at 60 °C and stir, and react in the dark for 24 h. d. After the reaction was complete, the sample was extracted with dichloromethane, dried with anhydrous magnesium sulfate, filtered and evaporated to dryness to obtain the crude product of dicyanvinyl-anthrayl probe. The crude product was then purified by recrystallization with methanol and column chromatography to obtain the red solid as dicyanvinyl-anthrayl probe. e. Dissolve the aldehyde-anthrayl probe obtained in step b and the dicyandiamide-anthrayl probe obtained in step d in tetrahydrofuran, respectively. After ultrasonic dissolution, prepare aldehyde-anthrayl probe solution and dicyandiamide-anthrayl probe solution with a concentration of 0.01-1 mmol / L to obtain two detection reagents for identifying amphetamine. Aldehyde-anthrayl probe for the detection of amphetamine: f. Take 450 μL of the aldehyde-anthrayl probe solution obtained in step e into a test tube, then add 50 μL of the amphetamine solution to be detected. After the reaction is complete, record the fluorescence spectrum and optical photograph under 365 nm ultraviolet light excitation conditions, and observe the signal changes of the fluorescence characteristic emission peaks before and after the reaction. Detection of amphetamine using a dicyandiamide-anthrayl probe: g. Take 450 μL of the dicyandiamide-anthrayl probe solution obtained in step e into a test tube, then add 50 μL of the amphetamine solution to be detected. After the reaction is complete, record the fluorescence spectrum and optical photograph under 365 nm ultraviolet light excitation conditions, and observe the signal changes of the fluorescence characteristic emission peaks before and after the reaction. Alternatively, a polyurethane sponge can be immersed in a 0.1 mmol / L dicyandiamide-anthrayl probe solution. After complete immersion, the sponge is removed and dried in an oven at 40°C until the solvent has completely evaporated, resulting in a sponge analysis card loaded with the dicyandiamide-anthrayl probe. 20 μL of the amphetamine solution to be detected is then added to the sponge analysis card loaded with the dicyandiamide-anthrayl probe, and colorimetric and fluorescence changes are observed under sunlight and 365 nm illumination.

Images