Cellulose acetate 1, 8-naphthalimide fluorescent probe for detecting hydrazine as well as preparation method and application of cellulose acetate 1, 8-naphthalimide fluorescent probe

Abstract

The invention discloses a cellulose acetate based 1, 8-naphthalimide fluorescent probe for detecting hydrazine as well as a preparation method and application of the cellulose acetate based 1, 8-naphthalimide fluorescent probe. The preparation method comprises the following steps: by taking 4-bromo-1, 8-naphthalic anhydride as a raw material, carrying out condensation reaction on the 4-bromo-1, 8-naphthalic anhydride and 4-aminobutyric acid to prepare 4-(4-bromo-1, 8-naphthalic diimide) butyric acid (BNA-B); the preparation method comprises the following steps: carrying out a coupling reaction on BNA-B and 4-formyl phenylboronic acid to prepare 4-(4-(4-formyl phenyl)-1, 8-naphthalimidoyl) butyric acid (FNA-B); and the compound FNA-B and cellulose acetate (CA) are subjected to an esterification reaction, such that the cellulose acetate-based 1, 8-naphthalimide fluorescent probe FNA-B-CA is prepared. The compound can specifically recognize hydrazine, after hydrazine is added into a DMF / H2O solution of FNA-B-CA under the irradiation of 365nm ultraviolet light, the fluorescence color of the solution is changed from bright blue to colorless, the detection limit of hydrazine reaches 8.4 * 10 <-8 > M, and the compound has a good application prospect as a fluorescent probe for detecting hydrazine.

Description

Technical Field

[0001] The invention belongs to the technical field of fluorescence detection, and relates to a cellulose acetate-based 1,8-naphthalene diimide fluorescent probe for detecting hydrazine, and a preparation method and application thereof. Background Art

[0002] Hydrazine is a colorless, oily liquid with a pungent odor. It will smoke and have a pungent odor when exposed to the air. Hydrazine has strong nucleophilicity and strong reducing properties. It is an important chemical raw material and can be widely used in aviation rockets and jet engine fuels, dyes, antioxidants, polymer crosslinkers, medicines, pesticides, plastics and other fields. Hydrazine has high toxicity, high activity alkalinity and good water solubility, which has brought great harm to environmental safety. It can enter the human body through oral and nasal inhalation, skin contact, drug intake, etc., destroying human DNA sequences, damaging the lungs, liver and central nervous system, etc., causing irreversible and serious harm to the human body. At present, the methods for detecting hydrazine mainly include electrochemical method, chemical titration method, spectrophotometry, etc. These methods have many limitations: cumbersome operation, insufficient practicality, low sensitivity, etc. In comparison, fluorescent probe technology has the advantages of easy operation and high sensitivity.

[0003] Cellulose is a natural polymer with a wide range of sources and abundant production. Each glucose ring of cellulose contains three hydroxyl groups, which can undergo oxidation, etherification, cross-linking, esterification and other reactions, thereby realizing the functional modification and application of cellulose and giving cellulose new properties. Cellulose acetate is the acetate ester of cellulose. As one of the derivatives of cellulose, it is more soluble in organic solvents than cellulose. In addition, it has the advantages of good biodegradability and mechanical properties, low cost and non-toxicity. Therefore, cellulose acetate has been widely used in food packaging materials, biosensors, electrochemistry and other fields in recent years. 1,8-Naphthalene diimide is a small molecule fluorophore with excellent performance and is often used in the field of fluorescent probes. However, this type of small molecule fluorescent probe has some disadvantages: high cytotoxicity, low quantum yield, poor processing performance, etc. Grafting small molecule fluorescent probes onto cellulose chains to obtain cellulose-based macromolecular fluorescent probes not only possesses the excellent properties of cellulose polymers themselves, but also overcomes many limitations of small molecule fluorescent compounds. At the same time, the small molecule fluorophore is connected to the cellulose skeleton with a stable chemical bond, which can effectively overcome the problem of easy loss of fluorescent small molecules in materials prepared by physical mixing of fluorescent small molecules with polymers. Therefore, the development of cellulose acetate-based macromolecular fluorescent probes is of great significance and has broad application prospects in the fields of biological imaging, detection sensing, information anti-counterfeiting, etc. Summary of the invention

[0004] In view of the deficiencies in the prior art, the technical problem to be solved by the present invention is to provide a cellulose acetate-based 1,8-naphthalene diimide fluorescent probe FNA-B-CA that can be used to detect hydrazine. The DMF / H2O solution of the fluorescent probe emits bright blue fluorescence under 365nm ultraviolet light, but the solution does not emit fluorescence after hydrazine is added, and can be used for the detection of hydrazine. Another technical problem to be solved by the present invention is to provide a method for preparing the above-mentioned cellulose acetate-based 1,8-naphthalene diimide fluorescent probe FNA-B-CA. Another technical problem to be solved by the present invention is to provide an application of the above-mentioned cellulose acetate-based 1,8-naphthalene diimide fluorescent probe FNA-B-CA.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A cellulose acetate-based 1,8-naphthalene diimide fluorescent probe FNA-B-CA for detecting hydrazine, the structural formula is:

[0007]

[0008] The method for preparing the cellulose acetate-based 1,8-naphthalene diimide fluorescent probe comprises the following steps:

[0009] (1) 4-bromo-1,8-naphthalene dicarboxylic anhydride reacts with 4-aminobutyric acid to prepare compound BNA-B;

[0010] (2) Compound BNA-B undergoes a coupling reaction with 4-formylphenylboronic acid to obtain compound FNA-B;

[0011] (3) Compound FNA-B undergoes an esterification reaction with the hydroxyl group on cellulose acetate to prepare the cellulose acetate-based 1,8-naphthalene diimide fluorescent probe FNA-B-CA.

[0012] The preparation steps of compound BNA-B in step (1) are as follows:

[0013] 1) In a 50 mL single-necked flask equipped with a stirrer, a thermometer and a reflux condenser, 1 mmol of 4-bromo-1,8-naphthalene dicarboxylic anhydride, 1-2 mmol of 4-aminobutyric acid and 20-40 mL of ethanol were added in sequence, and the mixture was stirred and refluxed at 80° C. for 4-6 hours; the reaction was monitored by TLC method, and the reaction was stopped after the reaction was complete;

[0014] 2) After the reaction was cooled to room temperature, the precipitated solid was filtered and washed with distilled water, and then vacuum dried at 45° C. for 24 to 36 hours to obtain compound BNA-B.

[0015] The preparation steps of compound FNA-B in step (2) are as follows:

[0016] 1) In a 50 mL three-necked flask equipped with a stirrer, a thermometer and a reflux condenser, 1 mmol of compound BNA-B, 20-30 mL of 1,4-dioxane, 2-3 mmol of 4-formylphenylboronic acid, and 5-10 mL of an aqueous solution of potassium carbonate (2 mol / L) were added in sequence, and the mixture was reacted at 90° C. for 20-40 min under a nitrogen environment.

[0017] 2) Add 0.1-0.2 mmol of tetrakis(triphenylphosphine)palladium to the above reaction solution, continue the reaction for 10-14 hours, monitor by TLC method, and stop the reaction after the reaction is complete;

[0018] 3) After the reaction, the solvent was evaporated, and dichloromethane was added for extraction three times. The organic phase was dried over anhydrous sodium sulfate, filtered, and concentrated to obtain a crude product, which was then purified by silica gel column chromatography (dichloromethane: methanol = 30:1) to obtain compound FNA-B.

[0019] The preparation steps of the fluorescent probe FNA-B-CA in step (3) are as follows:

[0020] 1) In a 100 mL three-necked flask equipped with a stirrer and a thermometer, 0.6-0.8 g of cellulose acetate, 1-2 mmol of compound FNA-B, 0.4-0.6 mmol of 4-dimethylaminopyridine and 50-70 mL of DMF were added in sequence, and reacted in an ice bath under a nitrogen environment for 20-40 min;

[0021] 2) Add 2-3 mmol of dicyclohexylcarbodiimide dissolved in 5 mL of DMF to the above reaction solution and continue the reaction at room temperature for 36-48 hours;

[0022] 3) After the reaction is completed, the reaction solution is poured into 200 mL of distilled water, the precipitate is filtered and washed with distilled water, and then vacuum dried at 45° C. for 24 to 36 hours to obtain the fluorescent probe FNA-B-CA.

[0023] The cellulose acetate-based 1,8-naphthalene diimide fluorescent probe is used in the detection of hydrazine. The DMF / H2O solution of the probe emits blue fluorescence under 365nm ultraviolet light. After adding hydrazine, the fluorescence color of the solution changes from blue to colorless, and can be used for the detection of hydrazine.

[0024] Beneficial effects: Compared with the prior art, the advantages of the present invention are as follows: Cellulose is the most widely distributed and abundant natural polymer in nature, with a wide range of sources and low prices. 1,8-Naphthalene diimide is a fluorophore with excellent performance and is often used in the field of fluorescent probes. The cellulose-based fluorescent probe obtained by grafting 1,8-naphthalene diimide derivatives onto the cellulose chain not only has the excellent performance of the cellulose polymer itself, but also overcomes the many limitations of small molecule fluorescent compounds. The fluorescent probe FNA-B-CA prepared in this way has the characteristics of good luminescence performance and stable structure. After hydrazine is added to the DMF / H2O solution of the probe under 365nm ultraviolet light, the fluorescent color of the solution gradually changes from blue to colorless, and the detection limit of hydrazine reaches 8.4×10 -8 M has good application prospects as a fluorescent probe for detecting hydrazine. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The infrared spectrum of CA, the infrared spectrum of the fluorescent probe FNA-B-CA, and the infrared spectrum of the compound FNA-B;

[0026] Figure 2 Fluorescence spectra of the fluorescent probe FNA-B-CA solution (DMF / H2O=2:8) before and after the addition of hydrazine;

[0027] Figure 3 Fluorescence spectra of the fluorescent probe FNA-B-CA solution (DMF / H2O=2:8) after adding different analytes;

[0028] Figure 4 Fluorescence spectra of the fluorescent probe FNA-B-CA solution (DMF / H2O=2:8) with different concentrations of hydrazine added. DETAILED DESCRIPTION

[0029] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the embodiments of the specification.

[0030] Example 1

[0031] The synthesis of the fluorescent probe FNA-B-CA is as follows:

[0032]

[0033] The specific steps are as follows:

[0034] 1) In a 50 mL single-necked flask equipped with a stirrer, a thermometer and a reflux condenser, 1 mmol 4-bromo-1,8-naphthalene dicarboxylic anhydride, 1.1 mmol 4-aminobutyric acid and 20 mL ethanol were added in sequence, and the mixture was stirred and refluxed at 80° C. for 4 h; the reaction was monitored by TLC and the reaction was stopped after the reaction was complete; the mixture was cooled to room temperature, and the precipitated solid was filtered and washed with distilled water, and then vacuum dried at 45° C. for 24 h to obtain compound BNA-B with a yield of 90%. 1 H NMR (600MHz, DMSO-d6) δ: 11.97 (s, 1H), 8.50 (dd, J=16.6, 7.9Hz, 2H), 8.27 (d, J=7.8Hz, 1H), 8.16 (d, J= 7.8Hz, 1H), 7.94 (t, J=7.9Hz, 1H), 4.03 (t, J=6.9Hz, 2H), 2.27 (t, J=7.3Hz, 2H), 1.85 (p, J=7.1Hz, 2H). 13 CNMR (150MHz, DMSO-d6) δ: 174.48, 163.42, 163.37, 132.91, 131.92, 131.7 2, 131.30, 130.16, 129.44, 129.16, 128.73, 123.23, 122.46, 31.81, 23.38.

[0035] 2) 1 mmol of compound BNA-B, 20 mL of 1,4-dioxane, 2 mmol of 4-formylphenylboronic acid, and 5 mL of potassium carbonate aqueous solution (2 mol / L) were added to a 50 mL three-necked flask equipped with a stirrer, a thermometer, and a reflux condenser, and the mixture was reacted at 90°C for 20 min under a nitrogen atmosphere. Then 0.1 mmol of tetrakis(triphenylphosphine)palladium was added to the reaction solution, and the reaction was continued for 12 h. The reaction was monitored by TLC until the reaction was complete and the reaction was stopped. After the reaction was completed, the solvent was evaporated, and dichloromethane was added for extraction 3 times. The organic phase was dried over anhydrous sodium sulfate, filtered, and concentrated to obtain a crude product, which was then purified by silica gel column chromatography (dichloromethane: methanol = 30: 1) to obtain compound FNA-B with a yield of 52%. 1 H NMR (600MHz, DMSO-d6) δ: 12.02 (s, 1H), 10.16 (s, 1H), 8.53 (q, J=9.1, 8.5Hz, 2H), 8.19 (dd, J=8.2, 3.9Hz, 1H), 8.13 (d, J =7.8Hz, 2H), 7.85 (t, J = 7.8Hz, 2H), 7.79 (d, J = 7.8Hz, 2H), 4.11 (t, J = 6.9Hz, 2H), 2.35-2.30 (m, 2H), 1.94-1.87 (m, 2H). 13C NMR (150MHz, DMSO-d6) δ: 192.78, 173.86, 163.31, 163.08, 144.36, 143.95, 135.73, 132.34, 131.55, 131.35 , 131.14, 130.67, 130.53, 130.06, 129.67, 128.80, 127.96, 127.75, 127.60, 122.39, 121.84, 31.18, 22.81.

[0036] 3) 0.6 g CA, 1 mmol compound FNA-B, 0.4 mmol 4-dimethylaminopyridine and 50 mL DMF were added to a 100 mL three-necked flask equipped with a stirrer and a thermometer, and the mixture was reacted in an ice bath under a nitrogen environment for 30 min; then 2 mmol dicyclohexylcarbodiimide dissolved in 5 mL DMF was added to the reaction solution, and the reaction was continued at room temperature for 48 h; after the reaction was completed, the reaction solution was poured into 200 mL distilled water, the precipitate was filtered and washed with distilled water, and then vacuum dried at 45° C. for 24 h to obtain the fluorescent probe FNA-B-CA.

[0037] The structure of the fluorescent probe FNA-B-CA was analyzed by FT-IR. Figure 1 The infrared spectra of CA, the infrared spectra of the fluorescent probe FNA-B-CA, and the infrared spectra of the compound FNA-B are shown in the figure. It can be seen from the figure that CA and FNA-B-CA have a strong affinity for 3511cm -1 The fluorescence probe FNA-B-CA shows an obvious characteristic absorption peak at 1700 cm -1 A new absorption peak appeared at , which belongs to the stretching vibration absorption peak of C=O, indicating that CA and FNA-B are connected through esterification reaction. In addition, the fluorescent probe FNA-B-CA also showed some new peaks belonging to the characteristic peaks of benzene ring, such as the skeleton vibration peaks of C=C (1590, 1516cm -1 ) and the bending vibration peak of carbon and hydrogen (783cm -1 ). Therefore, FT-IR analysis showed that the fluorescent probe FNA-B-CA was successfully prepared.

[0038] Example 2

[0039] The fluorescent probe FNA-B-CA was added to a DMF / H2O solution (DMF / H2O=2:8, v / v) to prepare a solution with a concentration of 0.025 mg / mL. The fluorescence emission spectrum was measured on a fluorescence spectrophotometer using a fluorescence spectrum titration method. Figure 2The results show that in DMF / H2O solution, the fluorescent probe FNA-B-CA emits a strong fluorescence intensity at 432nm, and after adding hydrazine, its fluorescence intensity at 432nm drops sharply. (The excitation wavelength is 360nm, the excitation slit bandwidth is 10nm, and the emission slit bandwidth is 3.5nm).

[0040] The fluorescent probe FNA-B-CA was added to DMF / H2O solution (DMF / H2O=2:8, v / v) to prepare a solution with a concentration of 0.025 mg / mL. One portion was used as a blank sample, and other analytes were added to the other portions. 1-15 were Ca 2+ Mg 2+ , Cu 2+ , Fe 2+ 、Zn 2+ , isoniazid, 2,4-dinitrophenylhydrazine, phenylhydrazine, acetylhydrazine, formic hydrazide, glycine, valine, leucine, cysteine, lysine, and the fluorescence emission spectrum of the solution was measured. The results were as follows Figure 3 As shown in the figure, after adding hydrazine, the fluorescence intensity of the solution at 432nm dropped sharply, while when other analytes were added, the fluorescence intensity of the solution at 432nm changed little. This shows that the fluorescent probe FNA-B-CA has good selectivity for the detection of hydrazine.

[0041] The fluorescent probe FNA-B-CA was added to a DMF / H2O solution (DMF / H2O=2:8, v / v) to prepare a solution with a concentration of 0.025 mg / mL. The fluorescence emission spectra after adding different concentrations of hydrazine (0-90 μM) were measured. Figure 4 The results showed that as the concentration of hydrazine gradually increased (0-90 μM), the fluorescence signal intensity of the fluorescent probe FNA-B-CA at 432 nm gradually weakened, indicating that the fluorescent probe FNA-B-CA can be used to detect the concentration of hydrazine in the solution, and the detection limit of hydrazine reached 8.4×10 -8 M.

Claims

1. A cellulose acetate-based 1,8-naphthalene diimide fluorescent probe for detecting hydrazine, characterized in that: The structural formula is:

2. The method for preparing the cellulose acetate-based 1,8-naphthalene diimide fluorescent probe FNA-B-CA according to claim 1, characterized in that: The steps include: (1) 4-bromo-1,8-naphthalene dicarboxylic anhydride reacts with 4-aminobutyric acid to prepare 4-(4-bromo-1,8-naphthalene diimido)butyric acid (BNA-B); (2) BNA-B undergoes a coupling reaction with 4-formylphenylboronic acid to obtain 4-(4-(4-formylphenyl)-1,8-naphthalene diimide)butyric acid (FNA-B); (3) The carboxyl group on FNA-B reacts with the hydroxyl group on cellulose acetate to produce the cellulose acetate-based 1,8-naphthalene diimide fluorescent probe FNA-B-CA.

3. The method for preparing the cellulose acetate-based 1,8-naphthalene diimide fluorescent probe according to claim 2, characterized in that: The specific preparation steps of BNA-B in step (1) are as follows: 1) Add 1 mmol 4-bromo-1,8-naphthalene dicarboxylic anhydride, 1-2 mmol 4-aminobutyric acid and 20-40 mL ethanol to a 50 mL single-necked flask equipped with a stirrer, a thermometer and a reflux condenser, stir and reflux at 80°C for 4-6 hours; monitor by TLC method, and stop the reaction when the reaction is complete; 2) After the reaction solution was cooled to room temperature, the precipitated solid was filtered, washed with distilled water, and then vacuum dried at 45° C. for 24 to 36 hours to obtain compound BNA-B.

4. The method for preparing the cellulose acetate-based 1,8-naphthalene diimide fluorescent probe according to claim 2, characterized in that: The specific preparation steps of FNA-B in step (2) are as follows: 1) In a 50 mL three-necked flask equipped with a stirrer, a thermometer and a reflux condenser, 1 mmol of compound BNA-B, 20-30 mL of 1,4-dioxane, 2-3 mmol of 4-formylphenylboronic acid and 5-10 mL of potassium carbonate aqueous solution (2 mol / L) were added in sequence, and the mixture was reacted at 90° C. for 20-40 min under a nitrogen environment. 2) Add 0.1-0.2 mmol of tetrakis(triphenylphosphine)palladium to the above reaction solution, continue the reaction for 10-14 hours, monitor by TLC method, and stop the reaction after the reaction is complete; 3) After the reaction, the solvent was evaporated, and dichloromethane was added for extraction three times. The organic phase was dried over anhydrous sodium sulfate, filtered, and concentrated to obtain a crude product, which was then purified by silica gel column chromatography (dichloromethane: methanol = 30:1) to obtain compound FNA-B.

5. The method for preparing the cellulose acetate-based 1,8-naphthalene diimide fluorescent probe according to claim 2, characterized in that: The preparation steps of FNA-B-CA in step (3) are as follows: 1) 0.6-0.8 g of cellulose acetate, 1-2 mmol of compound FNA-B, 0.4-0.6 mmol of 4-dimethylaminopyridine and 50-70 mL of DMF were added to a 100 mL three-necked flask equipped with a stirrer and a thermometer, and reacted in an ice bath under a nitrogen atmosphere for 20-40 min; 2) Add 2-3 mmol of dicyclohexylcarbodiimide dissolved in 5 mL of DMF to the above reaction solution and continue the reaction at room temperature for 36-48 hours; 3) After the reaction is completed, the reaction solution is poured into 200 mL of distilled water, the precipitate is filtered and washed with distilled water, and then vacuum dried at 45° C. for 24 to 36 hours to obtain the fluorescent probe FNA-B-CA.

6. Use of the cellulose acetate-based 1,8-naphthalene diimide fluorescent probe according to claim 1 in detecting hydrazine.

7. The use according to claim 6, characterized in that: Under 365nm ultraviolet light, the DMF / H2O solution of the fluorescent probe FNA-B-CA emits bright blue fluorescence. After adding hydrazine, the fluorescence color of the solution changes from blue to colorless.

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