Amino-functionalized zirconium-based metal organic framework sensing material for detecting nerve poison simulant diethyl cyano phosphate

Abstract

The invention provides an amino-functionalized zirconium-based metal organic framework sensing material for detecting nerve poison simulant diethyl cyano phosphate, which is characterized in that carboxylated nanocellulose is used for inducing in-situ growth of a metal organic framework and post-modification of o-phenylenediamine to obtain the small-size amino-functionalized metal organic framework sensing material. The material is used for constructing a nano-scale self-assembly film-forming type metal organic framework through cellulose-induced in-situ growth, so that the limitation of crystallization kinetics is overcome. When diethyl cyano phosphate is detected, enhanced release of a fluorescence signal is realized through an intramolecular charge transfer process between the detection reagent and diethyl cyano phosphate. The method has the advantages that the obviously low detection limit of 4.2 nM / 0.685 ppb and high selectivity to more than 21 common substances are realized, the problem of acid interference in the field of diethyl cyano phosphate detection can be particularly solved, and instant response to diethyl cyano phosphate steam is proved through a sensing chip; 1 s.

Description

Technical Field

[0001] The present invention relates to an amino-functionalized zirconium-based metal organic framework sensing material for detecting diethyl cyanophosphate, a nerve agent simulant. The present invention belongs to the field of analysis and detection, and realizes visual detection and application of diethyl cyanophosphate, a nerve agent simulant, through changes in fluorescence spectrum and fluorescence color. Background Art

[0002] The development of efficient and reliable detection materials and methods for nerve agents has important practical and strategic significance for human health and maintaining social security.

[0003] At present, the main detection methods for nerve agents include mass spectrometry, ion mobility chromatography, electrochemical sensors and biosensors, and some methods have good selectivity and repeatability. However, the application of these methods is often limited due to the need for expensive equipment, complex procedures and slow analysis. Fluorescence detection is widely used in rapid in situ detection and real-time monitoring of nerve agents and their simulants due to its advantages such as high sensitivity, good selectivity, simple operation and real-time analysis. As an emerging material, metal organic framework materials have high surface area, high porosity and rich recognition sites, and have special application prospects in both sensing and detection. The specific structure of metal organic frameworks can provide host-guest interactions, thereby selectively identifying target molecules. The pore advantages of metal organic frameworks can adsorb the analyte, thereby improving the detection performance. At the same time, it has many attractive advantages such as good portability, simple operation, high sensitivity, fast response speed, low cost and real-time monitoring, and is an ideal probe material for realizing fluorescent identification of nerve agents.

[0004] At present, metal-organic framework materials are used in the detection of nerve agents, mainly based on the degradation of organophosphorus nerve agents by metal-organic framework nanozymes, and the detection of nerve agents is achieved by detecting the corresponding degradation products (Chem. Mater. 2019, 31, 7417). There are also studies based on the fact that the action of nerve agents on metal-organic frameworks affects the charge transfer process between ligands and metal clusters, resulting in changes in fluorescence signals, thereby achieving the detection of nerve agents (J. Solid State Chem. 2022, 311, 123114). However, in the current research on metal-organic frameworks for the detection of nerve agents, how to prepare functional metal-organic framework nanocrystals and maximize the exposure of surface active sites by reducing the size is still a huge challenge for high-performance sensing.

[0005] In order to solve the existing problems, it is necessary to develop a general and sustainable preparation strategy to make the metal organic framework have a small size and expose more active sites on the surface, improve the interaction efficiency between the nanoscale metal organic framework and the analyte, so as to meet the demand of metal organic framework materials for efficient detection of diethyl cyanophosphate, and solve the insufficiency of on-site, rapid and accurate detection of tabun nerve agents. However, the inherent crystallization kinetics of metal organic framework materials determine that they usually aggregate in powder form, making their active sites poorly accessible and difficult to process and shape, which greatly hinders their practical application in the field of trace gas detection (Coordin. Chem. Rev. 2023, 497, 215454). Can a metal organic framework material (MOF)-based probe with rich active sites and efficient detection of the nerve agent simulant diethyl cyanophosphate be constructed through the functionalization of the metal organic framework material (MOF) structure and the regulation of the crystallization kinetics of the metal organic framework material (MOF) material synthesis process? Summary of the invention

[0006] The object of the present invention is to provide an amino-functionalized zirconium-based metal organic framework sensing material for detecting a nerve agent simulant diethyl cyanophosphate. The material is obtained by inducing in-situ growth of a metal organic framework by carboxylating nanocellulose and post-modifying o-phenylenediamine to obtain a small-sized amino-functionalized metal organic framework sensing material. The material is used to construct a nanoscale self-assembled film-forming metal organic framework through in-situ growth induced by cellulose, thereby overcoming the limitation of crystallization kinetics. Due to the increase in the surface-to-volume ratio of the nanoscale metal organic framework, more active sites are exposed on the surface of the nanoscale metal organic framework through further amino functionalization. When detecting diethyl cyanophosphate, enhanced release of fluorescent signals can be achieved through the intramolecular charge transfer process between the probe and diethyl cyanophosphate. Not only a significantly lower detection limit of 4.2nM / 0.685ppb and high selectivity for more than 21 common substances are achieved, especially the problem of acid interference in the field of diethyl cyanophosphate detection can be solved, and the instant response to diethyl cyanophosphate vapor <1s is proved by the sensor chip.

[0007] The amino-functionalized zirconium-based metal organic framework sensing material for detecting diethyl cyanophosphate, a nerve agent simulant, is prepared by carboxylating nanocellulose to induce in-situ growth of a metal organic framework and then post-modifying o-phenylenediamine to obtain a small-sized amino-functionalized metal organic framework sensing material. The specific operation is performed according to the following steps:

[0008] Prepare detection reagents:

[0009] a. Dissolve zirconium chloride and 2-bromoterephthalic acid in a 100mL polyvinyl fluoride reactor containing 17mL N,N-dimethylformamide, add 25.6mL acetic acid and 1mL deionized water, and then stir at 1000rpm for 20 minutes; disperse 3g of cellulose in 10mL N,N-dimethylformamide, stir evenly at 1500rpm, then add to the reactor and stir at 800rpm for another 10 minutes, finally put the reactor into an oven preheated to 120°C for 1 hour, wash the reaction solution with N,N-dimethylformamide and deionized water by centrifugation 3 times, and dry it in a freeze drying oven for 28 hours to obtain the product cellulose-induced in-situ growth zirconium-based metal organic framework material;

[0010] b. Disperse the zirconium-based metal organic framework material obtained in step a together with o-phenylenediamine in a 50 mL three-necked flask containing 25 mL toluene and continuously flowing nitrogen, add palladium acetate and potassium carbonate, condense and reflux, and react at a temperature of 100° C. for 24 hours; then centrifuge and wash with anhydrous ethanol solution and deionized water until the supernatant has no fluorescence, and dry the precipitate in a freeze drying oven for 28 hours to obtain the amino-functionalized zirconium-based metal organic framework material;

[0011] c. At room temperature, 2 mg of the amino-functionalized zirconium-based metal-organic framework material obtained in step b was weighed and dispersed in 10 mL of N,N-dimethylacetamide, and ultrasonically mixed until uniformly mixed to obtain an amino-functionalized zirconium-based metal-organic framework material detection reagent;

[0012] Sensor chip preparation:

[0013] d. 2 g of cellulose was dispersed in 10 mL of methanol and stirred for 8 hours to form a viscous suspension. Then 4 mg of amino-functionalized zirconium-based metal organic framework material detection reagent was added to the suspension and stirred for 24 hours to form a uniform dispersion. The dispersion was vacuum filtered to form a film. After the film was formed, it was dried in a vacuum drying oven at 90°C for 2 minutes to obtain a sensor chip.

[0014] Fluorescence detection of the nerve agent simulant diethyl cyanophosphate:

[0015] e. Take 200 μL of 0.01M analyte diethyl cyanophosphate solution, at a volume ratio of 1:9, and add it to the test bottle containing 1.8 mL of amino-functionalized zirconium-based metal organic framework material detection reagent obtained in step c, and react with the analyte to release green fluorescence at 546 nm to determine the presence of the nerve agent simulant diethyl cyanophosphate;

[0016] f. The sensor chip obtained in step d is placed in an atmosphere of diethyl cyanophosphate, a neurotoxin simulant. Under 395 nm ultraviolet light, the fluorescence of the sensor chip changes from colorless to yellow-green fluorescence.

[0017] The amino-functionalized zirconium-based metal-organic framework sensing material for detecting the nerve agent simulant diethyl cyanophosphate described in the present invention is a detection reagent prepared at room temperature by cellulose-induced in-situ growth and amino-functionalized zirconium-based metal-organic framework material and N,N-dimethylacetamide. The detection reagent is collected with a pipette and placed in a test bottle. The sample to be tested is dropped into the test bottle containing the detection reagent, which reacts with the detection reagent to produce a yellow-green fluorescent substance, thereby determining the presence of diethyl cyanophosphate.

[0018] The detection limit of the amino-functionalized zirconium-based metal organic framework sensing material for detecting the nerve agent simulant diethyl cyanophosphate provided by the present invention is 4.2nM / 0.685ppb.

[0019] Fluorescence detection of diethyl cyanophosphate:

[0020] Add the detection reagent to the test bottle, use a pipette to draw a trace amount of the test substance diethyl cyanophosphate, and drop it into the test bottle. Observe under a 395nm ultraviolet lamp whether the green fluorescence signal of the sample solution and the detection reagent is enhanced after the reaction to determine the presence of diethyl cyanophosphate.

[0021] The amino-functionalized zirconium-based metal organic framework sensing material for detecting the nerve agent simulant diethyl cyanophosphate described in the present invention has the following specific detection method:

[0022] a. Disperse 2 mg of the sensing material in 10 mL of N, N-dimethylacetamide solution to obtain a 0.2 mg / mL solution;

[0023] b. Use a pipette to measure 1.8 mL of the sensing material solution obtained in step a into a test bottle to obtain a detection reagent for detecting diethyl cyanophosphate;

[0024] c. Add 200 μL of 0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4 mM methanol solution of diethyl cyanophosphate to the detection reagent obtained in step b, respectively, and scan the fluorescence emission spectrum with a fluorescence spectrometer to measure the fluorescence emission spectrum of the reagent after detecting different concentrations of diethyl cyanophosphate under 420 nm excitation light; then use the fluorescence emission intensity at 420 nm as the ordinate and the diethyl cyanophosphate concentration as the abscissa to fit a linear curve to determine the fluorescence detection limit of the detection reagent, and the detection limit calculated based on the formula 3σ / k is 4.2 nM;

[0025] When the sensor chip is placed in an atmosphere of a nerve agent simulant (diethyl cyanophosphate), the fluorescence changes from colorless to yellow-green fluorescence under 395nm ultraviolet light, which can be used for real-time monitoring of diethyl cyanophosphate. The amino recognition site in the detection reagent undergoes a nucleophilic substitution reaction with the phosphocyanide bond in diethyl cyanophosphate. After detection, charge transfer occurs within the molecule, resulting in a change in fluorescence intensity. This achieves rapid, highly sensitive, and anti-interference detection of the nerve agent simulant diethyl cyanophosphate, providing an excellent research foundation for the field of nerve agent detection and monitoring.

[0026] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0027] The amino-functionalized zirconium-based metal organic framework sensing material for detecting diethyl cyanophosphate, a nerve agent simulant, according to the present invention, benefits from the significant increase in the number of active sites, the elimination of background fluorescence, and the excellent charge transfer between the amino group and the analyte, and a cellulose-induced in-situ grown amino-functionalized zirconium-based metal organic framework material-based efficient fluorescence platform for detecting diethyl cyanophosphonate (DCNP), a nerve agent analog, is established. Based on the nucleophilic reaction between the amino recognition site in o-phenylenediamine and the phosphorus-cyanide bond of diethyl cyanophosphonate (DCNP), a tabun nerve agent simulant, and the intramolecular charge transfer process between the probe material and diethyl cyanophosphonate (DCNP), the enhanced release of the fluorescence signal is achieved, thereby achieving rapid, naked eye, high sensitivity and super-specific recognition of DCNP, a tabun nerve agent simulant. The sensing reagent system changes from no fluorescence to yellow-green fluorescence emission under 395nm excitation, and its detection limit of 4.2nM / 0.685ppb is significantly lower. It has strong anti-interference to a variety of common interferences >21, and can especially eliminate the interference of common acids such as nitric acid, hydrochloric acid, phosphoric acid, hydrofluoric acid or acetic acid on the detection results, which solves the fatal problem of susceptibility to acid interference in the field of nerve agent detection. In addition, the probe material is integrated into the sensor chip to realize the instant sensing of DCNP vapor, and its response time can be as short as 1 second with super specificity. The synthesis strategy of uniformly dispersed small-sized MOF-based sensing materials of the present invention is not only expected to provide a new perspective for the preparation of controllable functional nanostructures, but also expected to realize high-performance nano-membrane-based chemical sensors with practical application potential. It solves the fatal problem in the field of nerve agent simulant probe design; moreover, the detection reagent system has a fast response speed, obvious fluorescent signal, and no obstacle to naked eye identification, providing an excellent theoretical basis and technical means for on-site detection of the nerve agent simulant diethyl cyanophosphate (diethyl cyanophosphate), and providing excellent basic research in the field of nerve agent safety detection and monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1Scanning electron microscope image and X-ray diffraction pattern of the amino-functionalized metal organic framework sensing material in Example 1 of the present invention; (a) is a scanning electron microscope image of the functionalized metal organic framework sensing material, and (b) is an X-ray diffraction spectrum of the functionalized metal organic framework sensing material;

[0029] Figure 2 Fluorescence changes between the amino-functionalized metal organic framework sensing material (0.2 mg / mL) N,N-dimethylacetamide solution and different concentrations of the nerve agent simulant diethyl cyanophosphate in Example 2 of the present invention, wherein (a) is a real-life graph of the fluorescence intensity change; (b) is the fluorescence spectrum data of the amino-functionalized metal organic framework sensing material detecting different concentrations of diethyl cyanophosphate, and (c) is the linear fit of the fluorescence intensity at 420 nm;

[0030] Figure 3 The specificity and anti-interference of the amino-functionalized metal organic framework sensing material (0.2 mg / mL) N,N-dimethylacetamide solution in Examples 3 and 4 of the present invention to potential interferents, structural analogs, common volatile solvents and acidic interfering substances (0.1 M) of the nerve agent simulant diethyl cyanophosphate are studied; wherein (a) is a physical diagram of the change in fluorescence intensity; (b) is the fluorescence spectrum data of the amino-functionalized metal organic framework sensing material detecting different interferent samples and mixed samples of interferents and diethyl cyanophosphate; (c) is the fluorescence intensity of the amino-functionalized metal organic framework sensing material detecting different interferent samples and mixed samples of interferents and diethyl cyanophosphate;

[0031] Figure 4 Scanning electron microscope image of the sensor chip constructed with the amino-functionalized metal organic framework sensor material in Example 5 of the present invention;

[0032] Figure 5 A photograph showing the fluorescence color change over time of the sensor chip constructed by the amino-functionalized metal organic framework sensing material in Example 6 of the present invention when exposed to a nerve agent simulant gas environment under a UV lamp at 395 nm;

[0033] Figure 6 Fluorescence photograph of the sensor chip constructed by the amino-functionalized metal organic framework sensing material in Example 7 of the present invention exposed to a gas environment of 19 common interfering substances of diethyl cyanophosphate under ultraviolet light at 395 nm. DETAILED DESCRIPTION

[0034] The present invention is further described in detail below through specific examples.

[0035] Example 1

[0036] Preparation of detection reagents:

[0037] a. Dissolve 84 mg, 0.36 mmol of zirconium chloride and 420 mg, 1.75 mmol of 2-bromoterephthalic acid in a 100 mL polyvinyl fluoride reactor containing 17 mL of N, N-dimethylformamide, add 25.6 mL of acetic acid and 1 mL of deionized water, and then stir at 1000 rpm for 20 minutes. Disperse 3 g of cellulose in 10 mL of N, N-dimethylformamide, stir evenly at 1500 rpm, and then add it to the reactor; stir at 800 rpm for another 10 minutes; finally, place the reactor in an oven preheated to 120 ° C for 1 hour, centrifuge the reaction solution with N, N-dimethylformamide for 3 times, wash it with deionized water for 3 times, and dry it in a freeze drying oven for 28 hours to obtain the product cellulose-induced in-situ growth zirconium-based metal organic framework material;

[0038] b. The zirconium-based metal organic framework material obtained in step a and 0.1732 g, 1.6 mmol of o-phenylenediamine were dispersed in a 50 mL three-necked flask filled with 25 mL of toluene and purged with nitrogen, 0.0200 g, 0.089 mmol of palladium acetate and 0.2000 g, 1.48 mmol of potassium carbonate were added, condensed and refluxed, reacted at a temperature of 100 ° C for 24 hours, and then washed by centrifugation with anhydrous ethanol solution and deionized water until the supernatant was free of fluorescence, and the precipitate was dried in a freeze drying oven for 28 hours to obtain the amino-functionalized zirconium-based metal organic framework material; Figure 1 The scanning electron microscope image and X-ray diffraction image of the amino-functionalized metal organic framework sensing material;

[0039] c. At room temperature, 2 mg of the amino-functionalized zirconium-based metal-organic framework material obtained in step b was weighed and dispersed in 10 mL of N,N-dimethylacetamide, and ultrasonicated until uniformly mixed. The concentration of the material in the solution was 0.2 mg / mL, and ultrasonicated until completely dispersed to obtain an amino-functionalized zirconium-based metal-organic framework material detection reagent;

[0040] Fluorescence detection of the nerve agent simulant diethyl cyanophosphate:

[0041] d. Use a pipette to measure 1.8 mL of the fluorescent probe detection reagent obtained in step a into a test bottle, and add 200 μL of 0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, and 0.4 mM diethyl cyanophosphate N,N-dimethylacetamide solutions, respectively, to obtain mixed solutions with diethyl cyanophosphate concentrations of 0-40 μM; use a fluorescence spectrometer to perform fluorescence emission spectrum scanning, indicating that the fluorescence emission intensity of the reagent after detecting different concentrations of diethyl cyanophosphate under 420 nm excitation light increases with the increase of diethyl cyanophosphate concentration; by establishing a linear relationship between the fluorescence intensity at 420 nm and the concentration of diethyl cyanophosphate (DCNP) solution, the linear equation y=5615x+24146( Figure 2 ), according to the detection limit calculation equation: detection limit = 3σ / k, where σ is the standard deviation of the fluorescence spectrometer used, the standard deviation of the fluorescence spectrometer used in the present invention is 7.2, and k is the slope of the fitted linear equation, that is, k = 5615. It can be calculated that the fluorescence detection limit of the reagent is 4.2nM. Figure 2 shown.

[0042] Figure 2 The results show that the fluorescence spectrum change of the amino-functionalized metal-organic framework sensing material shows a linear relationship with the change of diethyl cyanophosphate concentration. Therefore, this type of probe molecule has an excellent ability to detect diethyl cyanophosphate, and its fluorescence detection limit is as low as 4.2nM.

[0043] Example 2

[0044] At room temperature, the amino-functionalized zirconium-based metal organic framework material detection reagent obtained in step c of Example 1 was taken, and 1.8 mL of the detection reagent was measured with a pipette into a test bottle, and 200 μL of 0.01 M diethyl cyanophosphate and 0.1 M diethyl cyanophosphate structural analogs including diethyl chlorophosphate (DCP), ammonium thiocyanate (CH 4 N 2 S), dimethyl methylphosphonate (DMMP), phosphorus oxychloride (POCl 3 ), tributyl phosphate (TBP), triethyl phosphate (TEP), triphenyl phosphate (TPP), tert-butyl hypochlorite (t-Bu), 4-chlorobenzoyl chloride (4-CbC), diethyl phosphite (DP), propylene glycol methyl ether (1-m-2-p), acidic interfering substances including nitric acid (HNO 3 ), phosphoric acid (PA), hydrochloric acid (HCl), acetic acid (HAc), hydrofluoric acid (HF), various common volatile organic solvents, benzene (PhH), formaldehyde (CH 2 O), ethyl acetate (EA), dichloromethane (DCM), tetrahydrofuran (THF);

[0045] The fluorescence emission spectrum scanned by fluorescence spectrometer showed that when the reagent detected the structural analogs of the common nerve agent simulants or common volatile organic solvents or acids in the laboratory under 420nm excitation light, the fluorescence intensity or spectrum of the fluorescent solution hardly changed. After adding diethyl cyanophosphate, obvious green fluorescence appeared and the fluorescence spectrum changed dramatically, such as Figure 3 As shown, it is shown that the detection reagent has good specific recognition function for diethyl cyanophosphate.

[0046] Example 4

[0047] At room temperature, the amino-functionalized zirconium-based metal organic framework material detection reagent obtained in step c of Example 1 was taken, and 200 μL of 0.01M diethyl cyanophosphate was measured in a test bottle with a pipette, and 200 μL of 0.1M various diethyl cyanophosphate structural analogs including diethyl chlorophosphate (DCP), ammonium thiocyanate (CH 4 N 2 S), dimethyl methylphosphonate (DMMP), phosphorus oxychloride (POCl 3 ), tributyl phosphate (TBP), triethyl phosphate (TEP), triphenyl phosphate (TPP), tert-butyl hypochlorite (t-Bu), 4-chlorobenzoyl chloride (4-CbC), diethyl phosphite (DP), propylene glycol methyl ether (1-m-2-p), acidic interfering substances including nitric acid (HNO 3 ), phosphoric acid (PA), hydrochloric acid (HCl), acetic acid (HAc), hydrofluoric acid (HF), various common volatile organic solvents, benzene (PhH), formaldehyde (CH 2 O), ethyl acetate (EA), dichloromethane (DCM), tetrahydrofuran (THF), mixed evenly, and then added 1.8 mL of the obtained detection reagent;

[0048] The fluorescence emission spectrum scanned by fluorescence spectrometer showed that when the reagent detected the structural analogs of the common nerve agent simulants or common volatile organic solvents or acids in the laboratory under 420nm excitation light, the fluorescence intensity or spectrum of the fluorescent probe solution was almost unchanged compared with that of only adding diethyl cyanophosphate, and obvious green fluorescence appeared and the fluorescence spectrum changed dramatically, such as Figure 3 As shown, this indicates that the detection reagent has good anti-interference ability.

[0049] Example 5

[0050] Prepare detection reagents:

[0051] a. Dissolve 84 mg, 0.36 mmol of zirconium chloride and 420 mg, 1.75 mmol of 2-bromoterephthalic acid in a 100 mL polyvinyl fluoride reactor containing 17 mL of N, N-dimethylformamide, add 25.6 mL of acetic acid and 1 mL of deionized water, and then stir at 1000 rpm for 20 minutes. Disperse 3 g of cellulose in 10 mL of N, N-dimethylformamide, stir evenly at 1500 rpm, and then add it to the reactor; stir at 800 rpm for another 10 minutes; finally, place the reactor in an oven preheated to 120 ° C for 1 hour, centrifuge the reaction solution with N, N-dimethylformamide for 3 times, wash it with deionized water for 3 times, and dry it in a freeze drying oven for 28 hours to obtain the product cellulose-induced in-situ growth zirconium-based metal organic framework material;

[0052] b. The zirconium-based metal organic framework material obtained in step a and 0.1732 g, 1.6 mmol of o-phenylenediamine were dispersed in a 50 mL three-necked flask filled with 25 mL of toluene and purged with nitrogen, 0.0200 g, 0.089 mmol of palladium acetate and 0.2000 g, 1.48 mmol of potassium carbonate were added, condensed and refluxed, reacted at a temperature of 100 ° C for 24 hours, and then washed by centrifugation with anhydrous ethanol solution and deionized water until the supernatant was free of fluorescence, and the precipitate was dried in a freeze drying oven for 28 hours to obtain the amino-functionalized zirconium-based metal organic framework material; Figure 1 The scanning electron microscope image and X-ray diffraction image of the amino-functionalized metal organic framework sensing material;

[0053] c. At room temperature, 2 mg of the amino-functionalized zirconium-based metal-organic framework material obtained in step b was weighed and dispersed in 10 mL of N,N-dimethylacetamide, and ultrasonicated until uniformly mixed. The concentration of the material in the solution was 0.2 mg / mL, and ultrasonicated until completely dispersed to obtain an amino-functionalized zirconium-based metal-organic framework material detection reagent;

[0054] Sensor chip preparation:

[0055] 2 g of cellulose was dispersed in 10 mL of methanol and stirred for 8 hours to form a viscous suspension. Then 4 mg of detection reagent was added to the suspension and stirred for 24 hours to form a uniform dispersion. The prepared dispersion was vacuum filtered to form a film. After the film was formed, it was dried in a vacuum drying oven at 90°C for 2 minutes to obtain a sensor chip. Figure 4 This is a scanning electron microscope image of the sensor chip;

[0056] Response time of the sensor chip to diethyl cyanophosphate gas:

[0057] At room temperature, 0.1 mL of diethyl cyanophosphate liquid was placed in a sealed non-fluorescent glass bottle and allowed to stand for 5 minutes to obtain saturated diethyl cyanophosphate vapor. The obtained sensor chip was then placed in a glass bottle filled with saturated diethyl cyanophosphate gas and the fluorescence change time was recorded with a camera under a 395 nm ultraviolet lamp. Figure 5 As shown;

[0058] Figure 5 The results show that the sensor chip can achieve a stable response within 5 seconds when detecting nerve agent simulant (DCNP), and has the performance of rapid detection of nerve agent simulant (DCNP). Therefore, the sensor chip has the ability to rapidly detect nerve agent simulant (DCNP) and exhibits good detection performance.

[0059] Example 6

[0060] Selective test of sensor chip for diethyl cyanophosphate gas:

[0061] At room temperature, 0.1 mL of diethyl chlorophosphate (DCP), dimethyl methylphosphonate (DMMP), phosphorus oxychloride (POCl 3 ), tributyl phosphate (TBP), triethyl phosphate (TEP), tert-butyl hypochlorite (t-Bu), 4-chlorobenzoyl chloride (4-CbC), diethyl phosphite (DP), propylene glycol methyl ether (1-m-2-p), acidic interfering substances including nitric acid (HNO 3 ), phosphoric acid (PA), hydrochloric acid (HCl), acetic acid (HAc), hydrofluoric acid (HF), various common volatile organic solvents, benzene (PhH), formaldehyde (CH 2 O), ethyl acetate (EA), dichloromethane (DCM) and tetrahydrofuran (THF) were respectively placed in sealed non-fluorescent glass bottles to obtain the corresponding saturated gases. Then, the sensor chips were placed in the bottles containing saturated gases, and the fluorescence changes were recorded with a camera under a 395nm ultraviolet lamp. Figure 6 As shown;

[0062] Figure 6 The results show that the sensor chip has no similar reaction to 19 common interfering vapors of nerve agent simulants (DCNP) and has the performance of rapid detection of nerve agent simulants (DCNP). Therefore, the sensor chip has excellent sensing performance and applicability.

Claims

1. An amino-functionalized zirconium-based metal organic framework sensing material for detecting diethyl cyanophosphate, a nerve agent simulant, characterized in that The material is obtained by inducing the in-situ growth of a metal organic framework by carboxylating nanocellulose and post-modifying o-phenylenediamine to obtain a small-sized amino-functionalized metal organic framework sensing material. The specific operation is carried out in the following steps: Preparation of detection reagents: a. Dissolve zirconium chloride and 2-bromoterephthalic acid in a 100 mL polyvinyl fluoride reactor containing 17 mL N, N-dimethylformamide, add 25.6 mL acetic acid and 1 mL deionized water, and then stir at 1000 rpm for 20 minutes; disperse 3 g of cellulose in 10 mL N, N-dimethylformamide, stir evenly at 1500 rpm, then add it to the reactor and stir at 800 rpm for another 10 minutes, finally put the reactor into an oven preheated to 120 ° C for 1 hour, wash the reaction solution with N, N-dimethylformamide and deionized water by centrifugation 3 times, and dry it in a freeze drying oven for 28 hours to obtain the product cellulose-induced in-situ growth zirconium-based metal organic framework material; b. The zirconium-based metal organic framework material obtained in step a is dispersed together with o-phenylenediamine in a 50 mL three-necked flask containing 25 mL toluene and continuously flowing nitrogen, palladium acetate and potassium carbonate are added, condensed and refluxed, and reacted at a temperature of 100 ° C for 24 hours; then centrifuged and washed with anhydrous ethanol solution and deionized water until the supernatant has no fluorescence, and the precipitate is dried in a freeze drying oven for 28 hours to obtain the amino-functionalized zirconium-based metal organic framework material; c. At room temperature, 2 mg of the amino-functionalized zirconium-based metal-organic framework material obtained in step b was dispersed in 10 mLN, N-dimethylacetamide and ultrasonically mixed to obtain an amino-functionalized zirconium-based metal-organic framework material detection reagent; Sensor chip preparation: d. Disperse 2 g of cellulose in 10 mL of methanol and stir for 8 hours to form a viscous suspension. Then add 4 mg of amino-functionalized zirconium-based metal-organic framework material detection reagent to the suspension and stir for 24 hours to form a uniform dispersion. The dispersion is vacuum filtered to form a film. After the film is formed, it is dried in a vacuum drying oven at 90°C for 2 minutes to obtain a sensor chip. Fluorescence detection of the nerve agent simulant diethyl cyanophosphate: e. Take 200 µL of 0.01 M analyte diethyl cyanophosphate solution, at a volume ratio of 1:9, and add it to the test bottle containing 1.8 mL of amino-functionalized zirconium-based metal organic framework material detection reagent obtained in step c, and react with the analyte to release green fluorescence at 546 nm, thereby determining the presence of the nerve agent simulant diethyl cyanophosphate; f. The sensor chip obtained in step d is placed in an atmosphere of diethyl cyanophosphate, a neurotoxin simulant. Under 395 nm ultraviolet light, the fluorescence of the sensor chip changes from colorless to yellow-green fluorescence.

Images