Synthesis Method of an AIE Fluorescent Molecule and Its Application in the Detection of 2,4,6-Trinitrophenol
By synthesizing the AIE fluorescent molecule DVA-4P and preparing detection test strips, the existing fluorescent probes have poor selectivity and laboratory dependence when detecting 2,4,6-trinitrophenol, and high sensitivity and rapid detection effects have been achieved.
Patent Information
- Application Number
- CN202310551163.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-05-16
- Publication Date
- 2025-07-22
- Estimated Expiration
- 2043-05-16
AI Technical Summary
Existing fluorescent probes have poor selectivity and require laboratory equipment when detecting 2,4,6-trinitrophenol, making it difficult to achieve rapid and selective detection.
A kind of AIE fluorescent molecule DVA-4P was synthesized, and the selective detection of 2,4,6-trinitrophenol was achieved by preparing a rapid detection test strip.
High sensitivity and selective detection of 2,4,6-trinitrophenol is achieved, reducing the detection difficulty and suitable for immediate detection.
Smart Images
Figure CN116535347B_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the fields of organic light-emitting materials, chemical analysis, security inspection technology, etc., and particularly relates to a synthesis method of an AIE fluorescent molecule and its application in the detection of 2,4,6-trinitrophenol. Background Art
[0002] Fluorescence detection methods have the advantages of high sensitivity, good selectivity, low detection limit, fast response, etc., providing an efficient approach for biochemical analysis and can be used as a direct visualization tool in the field of point-of-care testing or fluorescence imaging. Among many fluorescent sensing materials, fluorescent organic small molecules have gained the favor of many scholars due to their easy preparation, low cost, variety, easy regulation of luminescence properties, and good biocompatibility. However, many fluorescent molecules (such as fluorescein, rhodamine, anthocyanin fluorescent molecules, etc.) have poor water solubility and will undergo aggregation-caused quenching (ACQ) in aqueous solutions, which greatly limits their practical applications. At the same time, the Stokes shifts of these fluorescent probes are usually small and are often interfered by complex environmental factors. Therefore, it is very necessary to synthesize organic fluorescent probes with high sensitivity, good selectivity, and excellent photophysical properties to overcome the ACQ effect.
[0003] Fluorescent molecules with AIE activity have a completely opposite luminescence mechanism to traditional fluorescent substances. Therefore, on the one hand, AIE molecules dispersed in a good solvent can easily achieve fluorescence enhancement detection; on the contrary, when AIE molecules are first dispersed in their poor solvents, the AIE molecules will not dissolve and aggregate to produce strong fluorescence. When it interacts with the analyte, the fluorescence decreases, thereby achieving fluorescence quenching detection. In addition, AIE molecules usually have large Stokes shifts and stronger anti-photobleaching abilities. The above characteristics and advantages provide favorable conditions for improving the sensitivity of AIE fluorescence sensors and reducing background noise. AIE-type fluorescent molecular probes can effectively complement the detection disadvantages of traditional fluorescent sensors, greatly expanding the application range of fluorescent probes.
[0004] 2,4,6-Trinitrophenol is an explosive with extremely strong explosive properties. Its performance even exceeds that of the well-known TNT explosive. Even a small amount of residual 2,4,6-trinitrophenol can cause serious soil and water pollution and safety hazards. Therefore, how to quickly and selectively detect 2,4,6-trinitrophenol is an important topic. At present, many fluorescent materials that can be used for the detection of 2,4,6-trinitrophenol have been developed. However, according to the existing literature, some deficiencies can be found. On the one hand, most of these materials are based on the strong absorption characteristics of 2,4,6-trinitrophenol molecules and cannot distinguish other nitroaromatic compounds, making it difficult to achieve the selective detection of 2,4,6-trinitrophenol. On the other hand, most of the methods for the detection of 2,4,6-trinitrophenol require laboratory instruments and equipment, are not suitable for use outside the laboratory, and cannot meet the requirements of timely detection. Summary of the Invention
[0005] The technical problems to be solved by the present invention are: to provide a synthesis method of an AIE fluorescent molecule and its application in the detection of 2,4,6-trinitrophenol; to realize the selective detection application of 2,4,6-trinitrophenol by using the structural characteristics of the molecule; and to reduce the detection difficulty and achieve instant detection by preparing a rapid detection test strip.
[0006] The present invention is realized as follows: An AIE fluorescent molecule, the AIE fluorescent probe is DVA-4P, and its structural formula is as follows:
[0007] 。
[0008] The present invention also provides a method for synthesizing an AIE fluorescent molecule, including the following steps:
[0009] Synthesize 9,10-bis(chloromethyl)anthracene, including: adding a certain amount of anthracene and excessive paraformaldehyde to a mixed solution composed of excessive hydrochloric acid solution and a certain amount of dioxane, then introducing HCl gas into the reactants to carry out chloromethylation reaction. After reacting for a period of time, cool and extract to obtain 9,10-bis(chloromethyl)anthracene;
[0010] Synthesize 9,10-bis(diethoxyphosphonomethyl)anthracene, including: reacting 9,10-bis(chloromethyl)anthracene with excessive triethyl phosphite under heating conditions. After reacting for a period of time, cool and extract to obtain 9,10-bis(diethoxyphosphonomethyl)anthracene;
[0011] Synthesis of DVA-4P includes: under a nitrogen atmosphere, adding 9,10-bis(diethoxyphosphonomethyl)anthracene and a base catalyst into tetrahydrofuran to obtain a first mixed solution, adding bis(2-pyridyl)ketone into tetrahydrofuran to obtain a second mixed solution, slowly dropping the second mixed solution into the first mixed solution, and after reacting for a period of time, extracting to obtain DVA-4P.
[0012] Further, in the process of synthesizing 9,10-bis(chloromethyl)anthracene, the introduction time of HCl gas is 2 h, and the reaction continues for 1 h after stopping the addition of HCl gas, then it is cooled to room temperature, and vacuum filtration is carried out and the filter cake is washed with dioxane solution and water to obtain 9,10-bis(chloromethyl)anthracene in the form of a yellow solid.
[0013] Further, in the process of synthesizing 9,10-bis(diethoxyphosphonomethyl)anthracene, after reacting for a period of time, it is cooled with ice water, then added to cold petroleum ether for suction filtration, and the filter cake is washed twice with cold petroleum ether to obtain 9,10-bis(diethoxyphosphonomethyl)anthracene in the form of a yellow solid.
[0014] Further, in the process of synthesizing DVA-4P, before dropping the second mixed solution, the first mixed solution is placed in an ice bath at 0 °C; after reacting for a period of time, the solvent is evaporated to dryness, redissolved in dichloromethane and then methanol is added, and then filtered. The filter cake is washed successively with cold methanol and distilled water, and the obtained solid product is placed in a vacuum oven for drying to obtain DVA-4P in the form of a yellow solid.
[0015] The present invention also provides a method for detecting 2,4,6-trinitrophenol based on solution, including the following steps:
[0016] Weigh a certain amount of AIE fluorescent molecules and prepare a tetrahydrofuran solution with a concentration of 10 mM; take the above tetrahydrofuran solution and prepare a mixed solution of tetrahydrofuran and water with a concentration of 100 μM, and use the mixed solution as the mother liquor for standby;
[0017] Take a certain amount of the mother liquor and add it equally to multiple TNP solutions with different concentrations respectively. After ultrasonic oscillation, the fluorescence intensity of each TNP solution at 510 nm is measured under excitation at 415 nm;
[0018] Take a certain amount of the mother liquor and add it equally to the mixed solutions respectively composed of 100 μM 2,4,6-trinitrophenol and 100 μM of any analogue respectively. After ultrasonic oscillation, the fluorescence intensity of each mixed solution at 510 nm is measured under excitation at 415 nm;
[0019] Compare the fluorescence intensity of the mixed solution with that of the TNP solution to obtain the interference degree of the analogue on the detection result.
[0020] Furthermore, the analog is one of 3,5-dinitrobenzoic acid, p-nitrophenol, hydroquinone, paracetamol, p-fluoronitrobenzene, phenylenediamine, and phthalic acid.
[0021] The present invention also provides a method for manufacturing a test strip, comprising the following steps:
[0022] Weigh a certain amount of an AIE fluorescent molecule as described above and prepare a tetrahydrofuran solution with a concentration of 10 mM; take the above tetrahydrofuran solution and prepare a mixed solution of tetrahydrofuran and water with a concentration of 100 μM, and use the mixed solution as the mother liquor for later use;
[0023] Soak a filter paper strip in the mother liquor for a period of time, take it out and air-dry it to obtain a test strip.
[0024] The present invention also provides a test strip manufactured by the method for manufacturing a test strip as described above.
[0025] The present invention also provides a method for detecting 2,4,6-trinitrophenol based on a test strip, comprising the following steps:
[0026] Prepare standard solutions of 2,4,6-trinitrophenol with different concentrations;
[0027] Drop the standard solutions onto corresponding test strips as described above respectively, and obtain corresponding standard images under the irradiation of a 365-nm ultraviolet lamp after the solvent has evaporated;
[0028] Drop a sample to be tested onto a test strip as described above, and obtain a test image under the irradiation of a 365-nm ultraviolet lamp after the solvent has evaporated;
[0029] Based on the comparison between the test image and the standard image, obtain the concentration range of 2,4,6-trinitrophenol in the sample to be tested.
[0030] The beneficial effects brought by the present invention are as follows: it can be used for the fluorescence detection of the explosive 2,4,6-trinitrophenol and has extremely high sensitivity and selectivity; the test strip for detecting 2,4,6-trinitrophenol developed based on the above fluorescent probe can greatly reduce the difficulty of detection and realize the rapid fluorescence colorimetric sensing of 2,4,6-trinitrophenol, and has high application value. Description of the Drawings
[0031] Figure 1 is a schematic diagram of the preparation route of the AIE fluorescent probe DVA-4P prepared in Example 1;
[0032] Figure 2 is the 1H NMR spectrum of the AIE fluorescent probe DVA-4P prepared in Example 1;
[0033] Figure 3 It is a graph showing the change in fluorescence intensity of the AIE fluorescent probe DVA-4P prepared in Example 1 upon addition of different concentrations of 2,4,6-trinitrophenol;
[0034] Figure 4 It is a linear working curve graph for the fluorescence detection of 2,4,6-trinitrophenol by the AIE fluorescent probe DVA-4P prepared in Example 1 (I is the fluorescence intensity upon addition of trinitrophenol, and I0 is the initial fluorescence intensity);
[0035] Figure 5 It is a selectivity detection graph of the AIE fluorescent probe DVA-4P prepared in Example 1 for 2,4,6-trinitrophenol;
[0036] Figure 6 It is a fluorescence response photo of the fluorescence rapid detection test strip prepared in Example 3 in response to 2,4,6-trinitrophenol. Detailed implementation mode
[0037] The present invention will be further described below with reference to the accompanying drawings. The following examples are only used to more clearly illustrate the technical solution of the present invention and cannot be used to limit the protection scope of the present invention. Example
[0038] An AIE fluorescent molecule, the AIE fluorescent probe is DVA-4P, and its structural formula is as follows:
[0039] 。 Example
[0040] A method for synthesizing the AIE fluorescent molecule in Example 1 includes the following steps:
[0041] Step 11: Synthesize 9,10-bis(chloromethyl)anthracene. This step includes: adding 200 mmol of anthracene, 30 g of paraformaldehyde, 40 ml of hydrochloric acid solution and 250 ml of dioxane into a three-necked flask to obtain a mixed solution, and then continuously introducing HCL gas into the reactants in the three-necked flask by using a hydrochloric acid generating device to carry out a chloromethylation reaction. This reaction is carried out under reflux conditions (heating the reactants to the boiling of the mixed solution), and after reacting for 2 h, the introduction of HCL gas is stopped, and then the reaction is continued for 1 h. The reaction solution in the three-necked flask is cooled to room temperature, and the filter cake is collected by suction filtration and washed with dioxane solution and water to obtain 9,10-bis(chloromethyl)anthracene in the form of a yellow solid. The yield of this step is 90%.
[0042] Step 12: Synthesize 9,10-bis(diethoxyphosphonomethyl)anthracene. This step includes: adding 16 mmol of 9,10-bis(chloromethyl)anthracene and 16 ml of triethyl phosphite into a single-necked flask, and reacting under stirring and refluxing conditions for 8 h. Cool the reaction solution with ice water, then add it to cold petroleum ether for suction filtration, and wash the filter cake twice with cold petroleum ether to obtain 9,10-bis(diethoxyphosphonomethyl)anthracene in the form of a yellow solid. The yield of this step is 80%.
[0043] Step 13: Synthesize DVA-4P. This step includes: under a nitrogen atmosphere, adding 5 mmol of 9,10-bis(diethoxyphosphonomethyl)anthracene, 5 mmol of a base catalyst, and 100 ml of anhydrous tetrahydrofuran into a two-necked flask to obtain a mixed solution I, and then placing the two-necked flask into an ice bath at 0 °C. The base catalyst is potassium tert-butoxide.
[0044] Add 12 mmol of bis(2-pyridyl)ketone and 20 ml of anhydrous tetrahydrofuran into a single-necked flask to obtain a mixed solution II.
[0045] Slowly add the mixed solution II dropwise to the mixed solution I. After the addition is completed, continue to stir at room temperature for 12 h. After the stirring ends, evaporate the solvent to dryness, add 5 ml of dichloromethane to redissolve it, then add 150 ml of methanol, and then filter. The filter cake is first washed 3 times with a small amount of cold methanol and once with distilled water. Place the obtained solid product in a vacuum oven for drying to obtain DVA-4P in the form of a yellow solid. The yield of this step is 84%.
[0046] Perform nuclear magnetic resonance analysis on the above probe DVA-4P using a nuclear magnetic resonance spectrometer, and the results are as follows:
[0047] 1 H NMR (300 MHz, CDCl3, unit: ppm): 8.80 (d, J = 4.9 Hz, 2H), 8.55 (s, 2H), 8.49 (d, J = 4.8 Hz, 2H), 8.25 (dd, J = 6.7, 3.3 Hz, 4H), 7.77 (t, J = 7.5 Hz, 2H), 7.44 - 7.31 (m, 8H), 6.99 (t, J = 7.4 Hz, 2H), 6.88 ((s, 2H), 6.64 (d, J = 9.9 Hz, 2H). The 1H NMR spectrum can be seen in Figure 2 . Example
[0048] In this example, the above probe molecule was used for fluorescence testing of 2,4,6-trinitrophenol in water. The process includes the following steps:
[0049] Step 21: Weigh 0.0538 g of the AIE fluorophore and prepare a 10 mM tetrahydrofuran solution in a 10 ml volumetric flask. Take 1 ml of the tetrahydrofuran solution and add it to a 100 ml volumetric flask, and then make up the volume to the mark with water under ultrasonic treatment to prepare a mixed solution of tetrahydrofuran and water with a concentration of 100 μM (the volume ratio of the two is: v THF / v water = 1:99), and use the mixed solution as the stock solution for later use.
[0050] Step 22: Take 100 μL of the stock solution and add it to multiple portions of TNP (0 - 100 μM) solutions with different concentrations respectively. The volume of each TNP solution is 900 μL. After ultrasonic oscillation for 2 min, measure the fluorescence intensity at 510 nm under the excitation light of 415 nm. As Figure 3 shown, the fluorescence intensity gradually quenches as the content of 2,4,6 - trinitrophenol increases. As Figure 4 shown, the linear working range of this probe is 0.5 - 2.2 μM and 2.2 - 50 μM. After calculation, the detection limit of this probe for 2,4,6 - trinitrophenol is 27.8 nM, which has a lower detection limit compared with the results reported in literatures such as Anal. Chem. 2014, 86, 7463 - 7470., Nanoscale, 2015, 7, 1872−1878..
[0051] Step 23: Take 100 μL of the stock solution and add it to multiple 900 μL mixed solutions composed of 100 μM 2,4,6 - trinitrophenol and 100 μM of any one of the analogs. The analogs are one of 3,5 - dinitrobenzoic acid, p - nitrophenol, hydroquinone, p - acetaminophen, p - fluoronitrobenzene, phenylenediamine, and phthalic acid, and a total of 7 portions of 900 μL mixed solutions are obtained. After ultrasonic oscillation for 2 min, measure the fluorescence intensity at 510 nm for each mixed solution under the excitation of 415 nm. As Figure 5 shown, based on the binding interaction between the pyridine group on the probe molecule and the hydroxyl group on 2,4,6 - trinitrophenol, this probe has good selectivity for 2,4,6 - trinitrophenol, while the influence of other similar benzene - based compounds on the detection is very small, which proves that other analogs have almost no interference on the detection process. Example
[0052] The present invention also provides a method for making a test strip, including the following steps:
[0053] Step 31: Weigh 0.0538 g of AIE fluorescent molecules and prepare a tetrahydrofuran solution with a concentration of 10 mM in a 10-ml volumetric flask. Take 1 ml of the tetrahydrofuran solution and add it to a 100-ml volumetric flask, and then make up the volume with water under ultrasonic treatment to prepare a mixed solution of tetrahydrofuran and water with a concentration of 100 μM (the volume ratio of the two is: v THF / v water = 1:99), and use the mixed solution as the stock solution for later use.
[0054] Step 32: Immerse a filter paper strip in the stock solution for 20 s, take it out and place it in a fume hood to dry naturally to obtain a test paper. Example
[0055] The present invention also provides a test paper prepared by the production method in Example 3. Example
[0056] The present invention also provides a method for detecting 2,4,6-trinitrophenol based on a test paper, which includes the following steps:
[0057] Step 41: Prepare 5 standard solutions of 2,4,6-trinitrophenol with concentrations of 1 μM, 5 μM, 10 μM, 50 μM, and 100 μM.
[0058] Step 42: Drop N portions of the standard solutions onto the corresponding test papers respectively. After the solvent evaporates, obtain N standard images under ultraviolet light irradiation at 365 nm. As Figure 6 shown, it can be observed that as the concentration of 2,4,6-trinitrophenol increases, the fluorescence intensity gradually weakens.
[0059] Step 43: Drop the sample to be tested onto the test paper. After the solvent evaporates, obtain a test image under ultraviolet light irradiation at 365 nm. In this step, the test image is obtained by visual observation or camera shooting under ultraviolet light irradiation.
[0060] Step 44: Compare the test image with the standard images one by one, and obtain the concentration range of 2,4,6-trinitrophenol in the sample to be tested according to the comparison results.
[0061] For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.
[0062] The above is only the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the technical field, without departing from the technical principle of the present invention, several improvements and deformations can be made, and these improvements and deformations should also be regarded as the protection scope of the present invention.
Claims
1. An AIE fluorescent molecule, characterized in that, The AIE fluorescent probe described above is DVA-4P, and its structural formula is as follows: 。 2. A method for synthesizing an AIE fluorescent molecule as claimed in claim 1, characterized in that, It includes the following steps: Synthesize 9,10-bis(chloromethyl)anthracene, including: adding a certain amount of anthracene and excessive paraformaldehyde into a mixed solution composed of excessive hydrochloric acid solution and a certain amount of dioxane, then introducing HCL gas into the reactants to carry out chloromethylation reaction. After reacting for a period of time, cool and extract to obtain 9,10-bis(chloromethyl)anthracene; Synthesize 9,10-bis(diethoxyphosphonomethyl)anthracene, including: reacting 9,10-bis(chloromethyl)anthracene with excessive triethyl phosphite under heating conditions. After reacting for a period of time, cool and extract to obtain 9,10-bis(diethoxyphosphonomethyl)anthracene; Synthesize DVA-4P, including: under a nitrogen atmosphere, adding 9,10-bis(diethoxyphosphonomethyl)anthracene and a base catalyst into tetrahydrofuran to obtain a mixed solution I, adding bis(2-pyridyl)ketone into tetrahydrofuran to obtain a mixed solution II, slowly dropping the mixed solution II into the mixed solution I. After reacting for a period of time, extract to obtain DVA-4P.
3. The method for synthesizing AIE fluorescent molecules according to claim 2, wherein During the process of synthesizing 9,10-bis(chloromethyl)anthracene, the introduction time of the HCL gas is 2 h. After stopping adding the HCL gas, continue to react for 1 h, then cool to room temperature, and perform suction filtration and wash the filter cake with dioxane solution and water to obtain 9,10-bis(chloromethyl)anthracene in the form of a yellow solid.
4. The method for synthesizing AIE fluorescent molecules according to claim 2, wherein During the process of synthesizing 9,10-bis(diethoxyphosphonomethyl)anthracene, after reacting for a period of time, cool with ice water, then add it to cold petroleum ether for suction filtration, and wash the filter cake with cold petroleum ether twice to obtain 9,10-bis(diethoxyphosphonomethyl)anthracene in the form of a yellow solid.
5. The method for synthesizing AIE fluorescent molecules according to claim 2, characterized in that, During the process of synthesizing DVA-4P, before dropping the mixed solution II, place the mixed solution I in an ice bath at 0 °C; after reacting for a period of time, evaporate the solvent, add dichloromethane to redissolve and then add methanol, then filter. The filter cake is washed successively with cold methanol and distilled water, and the obtained solid product is placed in a vacuum oven for drying to obtain DVA-4P in the form of a yellow solid.
6. A solution-based method for detecting 2,4,6-trinitrophenol, characterized in that, It includes the following steps: Weigh a certain amount of an AIE fluorescent molecule as described in claim 1 and prepare a tetrahydrofuran solution with a concentration of 10 mM; take the above tetrahydrofuran solution and prepare a mixed solution of tetrahydrofuran and water with a concentration of 100 μM, and use the mixed solution as the mother liquor for standby; Take a certain amount of the mother liquor and add it equally to multiple portions of TNP solutions with different concentrations. After ultrasonic oscillation, measure the fluorescence intensity of each TNP solution at 510 nm under excitation at 415 nm; Take a certain amount of the mother liquor and add it equally to mixed solutions respectively composed of 100 μM 2, 4, 6-trinitrophenol and 100 μM of any analogue. After ultrasonic oscillation, measure the fluorescence intensity of each mixed solution at 510 nm under excitation at 415 nm; The fluorescence intensity of the mixed solution was compared with that of the TNP solution to obtain the interference degree of the analog on the detection result; the analog was one of 3,5-dinitrobenzoic acid, p-nitrophenol, hydroquinone, paracetamol, p-fluoronitrobenzene, phenylenediamine and phthalic acid.
7. A method for manufacturing a test strip, characterized in that, It includes the following steps: Weigh a certain amount of an AIE fluorescent molecule as described in claim 1 and prepare a tetrahydrofuran solution with a concentration of 10 mM; take the above tetrahydrofuran solution and prepare a mixed solution of tetrahydrofuran and water with a concentration of 100 μM, and use the mixed solution as the mother liquor for standby; Soak a filter paper strip in the mother liquor for a period of time, take it out and air-dry it to obtain a test paper.
8. A test strip, characterized in that, It is made by the method for making a test paper as described in claim 7.
9. A test paper-based detection method for 2,4,6-trinitrophenol, characterized in that, It includes the following steps: Prepare standard solutions of 2,4,6-trinitrophenol with different concentrations; Drop the standard solutions onto the corresponding test paper as described in claim 8 respectively, and obtain the standard images with corresponding concentrations under the irradiation of a 365 nm ultraviolet lamp after the solvent evaporates; Drop the sample to be tested onto a test paper as described in claim 8, and obtain a test image under the irradiation of a 365 nm ultraviolet lamp after the solvent evaporates; According to the comparison between the test image and the standard image, obtain the concentration range of 2,4,6-trinitrophenol in the sample to be tested.