A zinc-based fluorescent probe containing a pyridyl carboxylic acid type component, and a preparation method and application thereof

Abstract

The present application relates to the technical field of organic synthesis, and particularly relates to a zinc-based fluorescent probe containing a pyridyl carboxylic acid type component, and a preparation method and application thereof. 22 H 14 N3O2)(CHO2)(H2O)·C3H7NO·3H2O; the zinc-based fluorescent probe containing the pyridyl carboxylic acid type component belongs to a monoclinic system, and a space group is P 2 1 / c ; cell parameters are a = 7.2925(2) Å, b = 26.6839(8) Å, c = 12.8618(4) Å, α = 90°, β = 105.5770(10)°, gamma = 90°. The zinc-based fluorescent probe has good thermal stability and large light emission intensity, the preparation method is simple, and the zinc-based fluorescent probe can be used as a fluorescent sensor to detect Fe 3+ and 2,4,6-trinitrophenol in a DMF solution with high sensitivity and high selectivity.

Description

Technical Field

[0001] This invention relates to the field of organic synthesis technology, and in particular to a zinc-based fluorescent probe containing a pyridyl carboxylic acid type component, its preparation method, and its application. Background Technology

[0002] With the booming development of the chemical industry, factories are emitting increasingly more pollutants. Metal ions and nitroaromatic hydrocarbons (NACs) among these pollutants have attracted widespread attention due to their threat to the ecological environment and public safety. Many metal ions, especially highly charged metal ions, can cause irreversible damage to organisms and ecosystems if released into the environment. When concentrations are too high, Fe... 3+ Ions are also considered toxic pollutants. Nitroaromatic hydrocarbons (NACs) (such as 2,4,6-trinitrophenol, p-nitrophenol, and 4-nitrobenzene) are highly toxic chemicals found in the industrial production of dyes, pharmaceuticals, explosives, and paints. They irritate the eyes, respiratory tract, and skin, threatening human health and life. Furthermore, NACs are strong oxidizers; they react violently with reducing agents, leading to explosions, which are extremely harmful to society. Therefore, effective detection of NACs is of great significance to people's production and daily life. Currently, traditional methods for detecting ions / molecules mainly include mass spectrometry, gas chromatography, high-performance liquid chromatography, Raman spectroscopy, ion mobility spectrometry, and atomic absorption spectrometry. However, these traditional detection methods suffer from drawbacks such as complex operation, inconvenient equipment, and high detection costs. Therefore, it is essential to develop a rapid, convenient, effective, and inexpensive detection technology for metal ions and NACs.

[0003] Fluorescent coordination polymers are considered promising sensors due to their tunable properties, designed functional structures, and unique fluorescence response characteristics. Although significant progress has been made in the synthesis and fluorescence detection applications of fluorescent metal-organic frameworks (MOFs), new fluorescent MOFs remain anticipated due to their greater structural diversity and intriguing applications. Therefore, designing a sensor capable of simultaneously detecting Fe... 3+ The bifunctional fluorescent probes of TNP are of great significance. Summary of the Invention

[0004] The purpose of this invention is to overcome the drawbacks of traditional fluorescent materials, such as high synthesis cost and environmentally unfriendly synthesis process, and to provide a zinc-based fluorescent probe containing a pyridyl carboxylic acid type component, its preparation method, and its application. This zinc-based fluorescent probe has good thermal stability and a high pyrolysis temperature, and can be used as a dual-function fluorescent sensor to detect Fe in N,N-dimethylformamide (DMF) solution with high sensitivity and high selectivity. 3+2,4,6-Tinitrophenol (TNP) is a novel product synthesized in the laboratory, which has not been reported before. Its preparation method is simple, the synthesis time is short, the raw materials are readily available, and it has a wide range of applications.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0006] This invention provides a zinc-based fluorescent probe containing a pyridyl carboxylic acid type component, with the chemical formula Zn(C 22 H 14 N3O2)(CHO2)(H2O)·C3H7NO·3H2O;

[0007] Zinc-based fluorescent probes containing pyridyl carboxylic acid type components belong to the monoclinic crystal system, space group 1. P 2 1 / c The unit cell parameters are a =7.2925(2)Å, b =26.6839(8)Å, c =12.8618(4)Å, α =90°, β =105.5770(10)°, γ =90°.

[0008] This invention also provides a method for preparing the zinc-based fluorescent probe containing pyridyl carboxylic acid type components described above, comprising the following steps:

[0009] Zinc nitrate hexahydrate, 4-[4,2':6',4''-terpyridine]-4'-ylbenzoic acid, N,N-dimethylformamide and water were mixed and subjected to a solvothermal reaction under closed conditions to obtain a zinc-based fluorescent probe containing a pyridine carboxylic acid component.

[0010] Optionally, the molar ratio of zinc nitrate hexahydrate to 4-[4,2':6',4''-terpyridine]-4'-yl-benzoic acid is 0.9 to 1:1.

[0011] Optionally, the volume ratio of N,N-dimethylformamide to water is 4.9 to 5:1.

[0012] Optionally, the ratio of zinc nitrate hexahydrate to N,N-dimethylformamide is 0.009~0.01 mmol: 0.5~0.6 mL.

[0013] Optionally, the temperature of the solvothermal reaction is 105~110℃ and the time is 46~48h.

[0014] Optionally, after the solvothermal reaction is completed, the temperature is reduced to 15-30°C at a rate of 5-10°C / h.

[0015] The present invention also provides a method for detecting Fe in N,N-dimethylformamide solution. 3+ A bifunctional fluorescent sensor for 2,4,6-trinitrophenol, comprising the zinc-based fluorescent probe containing the pyridyl carboxylic acid type component described above.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] (1) A zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component of the present invention. The complex is a novel fluorescent material. The material slowly crystallizes under programmed temperature control to produce a regular morphology. The polymer has good thermal stability, high pyrolysis temperature, and high luminescence intensity.

[0018] (2) A method for preparing a zinc-based fluorescent probe compound containing a pyridine carboxylic acid type component according to the present invention is to prepare the novel zinc-based fluorescent probe compound containing a pyridine carboxylic acid type component by a solvothermal method. The preparation process is simple and easy to operate, the synthesis time is short and the reaction is fast, the raw materials are abundant, the production cost is low, the yield is high, the experimental reproducibility is good, and the environment is friendly.

[0019] (3) Application of a zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component of the present invention. This novel zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component is used for fluorescence detection. The complex can be used as a bifunctional fluorescent sensor to cyclically detect Fe in N,N-dimethylformamide (DMF) solution with high sensitivity and high selectivity. 3+ And 2,4,6-trinitrophenol (TNP). Attached Figure Description

[0020] Figure 1 This is an asymmetric unit structure diagram of a zinc-based fluorescent probe compound containing a pyridine carboxylic acid type component according to the present invention;

[0021] Figure 2 This is a monolayer structure diagram (along the a-axis direction) of a zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component according to the present invention.

[0022] Figure 3 This is a two-dimensional layered structure diagram (along the b-axis) of a zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component according to the present invention.

[0023] Figure 4 This is a topological structure diagram of a zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component according to the present invention;

[0024] Figure 5 This is an X-ray diffraction pattern of a zinc-based fluorescent probe compound powder containing a pyridyl carboxylic acid type component according to the present invention;

[0025] Figure 6Thermogravimetric analysis diagram of a zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component according to the present invention;

[0026] Figure 7 The fluorescence intensity of a zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component of the present invention in different ionic solutions;

[0027] Figure 8 This invention relates to a zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component, with Fe at different concentrations. 3+ Fluorescence intensity in solution;

[0028] Figure 9 This invention relates to a zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component, with Fe at different concentrations. 3+ Stern-Volmer plot in solution;

[0029] Figure 10 This is a Stern-Volmer diagram of a zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component of the present invention at different metal ion concentrations.

[0030] Figure 11 The fluorescence intensity of a zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component according to the present invention in different nitro explosive solutions;

[0031] Figure 12 The fluorescence intensity of a zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component of the present invention in TNP solutions of different concentrations;

[0032] Figure 13 This is a Stern-Volmer diagram of a zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component of the present invention in TNP solutions of different concentrations;

[0033] Figure 14 This is a Stern-Volmer plot of a zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component of the present invention at different concentrations of nitro compounds;

[0034] Figure 15 This is an X-ray diffraction pattern of a simulated zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component, and the powder after four detection cycles, according to the present invention. Detailed Implementation

[0035] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0036] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0037] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0038] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be obvious to those skilled in the art. This application specification and embodiments are merely exemplary.

[0039] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0040] All raw materials used in this invention can be obtained commercially or prepared using existing technologies.

[0041] Understandably, current reports on MOF-based fluorescent sensors demonstrate that introducing electron-rich aromatic ligands can effectively improve sensing performance. Considering the above, 4-[4,2':6',4''-terpyridine]-4'-ylbenzoic acid (Hcptpy) can be considered an excellent ligand for preparing functional coordination polymers: (a) Hcptpy, as a semi-rigid bridging ligand, can connect metal ions through coordination bonds to construct high-dimensional, honeycomb-like porous coordination polymers; (b) it has a large π-conjugated nonlinear structure with N and O donors, which can provide additional hydrogen bonds and π-π interactions to consolidate the entire framework structure; (c) due to the steric hindrance effect generated by the two terminal pyridine groups, metal ions prefer to bind to the carboxylate O atom in Hcptpy and the N atoms of the two terminal pyridine groups rather than the N atom of the central pyridine, thus predicting that the N atom will act as a functional site to recognize small Lewis acid molecules and metal ions. Zinc ions are the second largest metal ion in mammals after iron, and their toxicity and carcinogenicity are lower than cadmium and mercury. Meanwhile, zinc ion complexes cannot undergo dd transitions because the d(10) electron level is filled. Therefore, most zinc ion complexes exhibit photoluminescence and electroluminescence properties, while those with conjugated organic ligands exhibit dd transitions. 10 Metal complexes enhance fluorescence properties and function as sensors. Therefore, based on these considerations, this invention utilizes Hcptpy ligands to construct a novel organometallic complex Zn(C) with zinc ions. 22 H 14 N3O2)(CHO2)(H2O)·C3H7NO·3H2O.

[0042] This invention provides a zinc-based fluorescent probe containing a pyridyl carboxylic acid type component, with the chemical formula Zn(C 22 H 14 N3O2)(CHO2)(H2O)·C3H7NO·3H2O; Molecular formula is C 26 H 30 ZnN4O9 has a molecular weight of 607.86;

[0043] Zinc-based fluorescent probes containing pyridyl carboxylic acid type components belong to the monoclinic crystal system, space group 1. P 2 1 / c The unit cell parameters are a =7.2925(2)Å, b =26.6839(8)Å, c =12.8618(4)Å, α =90°, β =105.5770(10)°, γ =90°.

[0044] This invention also provides a method for preparing the zinc-based fluorescent probe containing pyridyl carboxylic acid type components described above, comprising the following steps:

[0045] Zinc nitrate hexahydrate, 4-[4,2':6',4''-terpyridine]-4'-ylbenzoic acid, N,N-dimethylformamide and water were mixed and subjected to a solvothermal reaction under closed conditions to obtain a zinc-based fluorescent probe containing a pyridine carboxylic acid component.

[0046] In some embodiments of the present invention, zinc nitrate hexahydrate, 4-[4,2':6',4''-terpyridine]-4'-ylbenzoic acid, N,N-dimethylformamide and water are mixed and sonicated for 10 minutes to fully dissolve them, thereby obtaining a mixture.

[0047] The mixture was transferred to a reaction vessel, sealed and heated, and reacted under autogenous pressure. Then it was cooled to room temperature at a rate of 5°C / h, washed, filtered, and naturally dried to obtain the zinc-based fluorescent probe containing the pyridyl carboxylic acid type component.

[0048] In this invention, the molar ratio of zinc nitrate hexahydrate to 4-[4,2':6',4''-terpyridine]-4'-yl-benzoic acid is 0.9 to 1:1, preferably 1:1.

[0049] In this invention, the volume ratio of N,N-dimethylformamide to water is 4.9 to 5:1, preferably 5:1.

[0050] In this invention, the ratio of zinc nitrate hexahydrate to N,N-dimethylformamide is 0.009~0.01mmol:0.5~0.6mL, preferably 0.01mmol:0.5mL.

[0051] To avoid the drawbacks of high cost and environmentally unfriendly synthesis processes in traditional fluorescent materials, the inventors, through repeated theoretical analysis and numerous experiments, finally developed a method using readily available and inexpensive Zn(NO3)2·6H2O and 4-[4,2':6',4''-terpyridine]-4'-ylbenzoic acid (C 22 H 15 Using N3O2 as a reactant, and employing a solvothermal method, the aforementioned novel zinc-based fluorescent probe compound with excellent fluorescence properties containing a pyridyl carboxylic acid component can be prepared. The specific reaction schematic is as follows:

[0052] Zn(NO3)2·6H2O+C 22 H 15 N3O2 + C3H7NO → Zn(C 22 H 14 N3O2)(CHO2)(H2O)·C3H7NO·3H2O.

[0053] In this invention, the temperature of the solvothermal reaction is 105~110℃, preferably 110℃, and the time is 46~48h, preferably 48h.

[0054] In this invention, after the solvothermal reaction is completed, the temperature is reduced to room temperature at a rate of 5~10℃ / h (preferably 5℃ / h), where the room temperature is 15~30℃, preferably 20℃.

[0055] This invention discloses a zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component, which is a novel fluorescent material. Under programmed temperature control, it slowly crystallizes to produce a regular morphology. Furthermore, this polymer exhibits good thermal stability, a high pyrolysis temperature, and high luminescence intensity. It can serve as a dual-function fluorescent sensor for highly sensitive and selective cyclic detection of Fe in N,N-dimethylformamide (DMF) solution. 3+ And 2,4,6-trinitrophenol (TNP).

[0056] This invention utilizes the advantages of the classic solvothermal method, which is simple, environmentally friendly, and easy to operate. Furthermore, through repeated experiments, the process parameters were optimized, resulting in a complex with good thermal stability, high pyrolysis temperature, and high luminescence intensity. Simultaneously, the synthesis time was shortened, the yield increased, and the production cost significantly reduced. The zinc-based fluorescent probe compound containing a pyridine carboxylic acid component and its preparation method described in this embodiment have significant potential for widespread application.

[0057] The zinc-based fluorescent probe containing a pyridyl carboxylic acid component of the present invention can be used for fluorescence detection and can serve as a dual-function fluorescent sensor for highly sensitive and selective detection of Fe in N,N-dimethylformamide (DMF) solution. 3+ And 2,4,6-trinitrophenol (TNP).

[0058] The present invention also provides a method for detecting Fe in N,N-dimethylformamide solution. 3+ A bifunctional fluorescent sensor for 2,4,6-trinitrophenol, comprising the zinc-based fluorescent probe containing the pyridyl carboxylic acid type component described above.

[0059] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0060] Example 1

[0061] 1) Weigh 0.01 mmol of 4-[4,2':6',4''-terpyridine]-4'-yl-benzoic acid and 0.01 mmol of Zn(NO3)2·6H2O and place them in a reaction flask;

[0062] 2) Add 0.5 mL of DMF and 0.1 mL of H2O to step 1), and sonicate for 10 min to ensure complete dissolution;

[0063] 3) The mixed solution obtained in step 2) was transferred to a 25 mL steel reactor with a polytetrafluoroethylene liner, sealed, and heated to 110 °C. The reactor was reacted under autogenous pressure for 48 h, and then cooled to room temperature (20 °C) at a rate of 5 °C / h. The solution was washed, filtered, and naturally dried to obtain 0.047 g of the zinc-based fluorescent probe containing the pyridyl carboxylic acid type component. The yield was approximately 78% with 4-[4,2':6',4''-terpyridine]-4'-yl-benzoic acid as a reference.

[0064] Test Example 1

[0065] The structure and physicochemical properties of the novel zinc-based fluorescent probe containing a pyridine carboxylic acid component in this embodiment were analyzed by combining X-ray single-crystal diffractometer, X-ray powder diffractometer, thermogravimetric analyzer, and fluorescence spectrometer. The chemical formula of the zinc-based fluorescent probe is Zn(C). 22 H 14 N3O2)(CHO2)(H2O)·C3H7NO·3H2O, the structural unit of this complex belongs to the monoclinic crystal system, and the molecular formula is C. 26 H 30 ZnN4O9, with a molecular weight of 607.86 and space group [missing information], is a space group [missing information]. P 2 1 / c The unit cell parameters are: a =7.2925(2)Å, b =26.6839(8)Å, c =12.8618(4)Å, α =90°, β =105.5770(10)°, γ =90°;

[0066] like Figure 1As shown, a notable structural feature of this complex is that the asymmetric unit consists of a single Zn(II) ion, a deprotonated 4-[4,2':6',4''-terpyridine]-4'-yl-benzoic acid ligand, a formate ligand, and a coordinated water molecule. It should be noted that the monodentate formate ligand originates from the decomposition of DMF under solvothermal conditions. Zn1 adopts a distorted cis-octahedral geometry, coordinated by four oxygen atoms (O1a, O2a, O4, O3w) and two nitrogen atoms (N1b, N3). The chelated carboxyl groups (O1a, O2a) and the two pyridyl N atoms (N1b, N3) are located in the equatorial plane. Formate O4 and water O3W atoms occupy axial positions. Each deprotonated 4-[4,2':6',4''-terpyridine]-4'-yl-benzoic acid ligand binds to three Zn(II) ions through chelation of the carboxyl group and two external pyridine groups, constructing a 2D porous layered network (e.g. Figure 2 , Figure 3 (As shown). Deprotonated 4-[4,2':6',4''-terpyridine]-4'-yl-benzoic acid ligands were used as triple-connected spacers, and Zn(II) ions were used as triple-connected nodes to generate a hexagonal honeycomb microporous network (as shown). Figure 2 As shown). Two 2D porous networks are interleaved to create a double-layered interpenetrating network structure (as shown). Figure 4 (As shown).

[0067] X-ray powder diffraction analysis indicates (e.g.) Figure 5 As shown): The diffraction data of the complex powder sample in this embodiment are consistent with those of the single-crystal simulation, indicating high phase purity.

[0068] Thermogravimetric analysis was performed on the novel zinc-based fluorescent probe compounds containing pyridyl carboxylic acid components: sample amount approximately 5–10 mg, measurement range 25–750 °C, heating rate 10 °C / min, N2 protection. Figure 6 As shown, the sample gradually loses weight before 256°C, corresponding to the loss of water of crystallization and crystalline DMF molecules in the framework. With increasing temperature, coordinated water molecules are subsequently lost, and framework collapse only begins at 358°C. Analysis indicates that the complex powder of this embodiment exhibits high thermal stability, meeting the requirements of practical production and daily life.

[0069] Test Example 2

[0070] Fluorescence detection of Fe by the novel zinc-based fluorescent probe containing pyridyl carboxylic acid type components was performed. 3+ Performance testing: Finely ground samples (2.0 mg) of the complex were dispersed in a solution containing M(NO3). x In a solution of N,N-dimethylformamide (DMF) (2.0 mL) (1 × 10⁻⁶) -3 mol / L; M=Co2+ Na + Cd 2+ Pb 2+ Ni 2+ Cu 2+ Ba 2+ Al 3+ Cr 3+ Sr 2+ Ca 2+ Fe 3+ The suspension was sonicated for 30 minutes, and the fluorescence spectrum of the suspension was measured and recorded at room temperature.

[0071] like Figure 7 As shown, almost all metal ions quench the fluorescence of the complex to varying degrees, while Fe... 3+ The ions exhibited excellent fluorescence quenching effects, with quenching rates all exceeding 90%. To further investigate, different concentrations of Fe were used... 3+ Fluorescent titration experiments were performed on the ionic suspension. For example... Figure 8 As shown, the fluorescence intensity of the complex increases with increasing Fe concentration. 3+ The temperature gradually decreases as the temperature increases. When Fe 3+ When the concentration is in the low concentration range, Fe 3+ The concentration of the complex showed a linear correlation with the fluorescence quenching of the complex (e.g. Figure 9 (As shown). The quenching phenomenon can be expressed using the Stern-Volmer equation (I0 / I) = K sv ×[M] +1 To explain, the quenching constant (K) sv The fluorescence intensity (I0) reflects the sensor's sensitivity, I is the initial fluorescence intensity, I is the fluorescence intensity after adding the analyte, and [M] is the molar concentration of the analyte. This is used to detect Fe. 3+ K of ionic complexes sv The value is calculated to be 1.55 × 10. 5 M -1 This is higher than most reported MOF-based sensors. Furthermore, it achieves a minimum detection limit (LOD) of 3σ / K. sv (σ is the standard deviation of the luminescence intensity of the control sample of the complex, K) sv The ratio of the Stern-Volmer slope was used to calculate the complex pair for Fe. 3+ The LOD is 0.12 μM, which is lower than that of Fe-based materials. 3+ Various literature reports on sensing. Relatively high K. sv The high value and low detection limit further indicate that the complex can serve as a sensitive Fe... 3+ Ion chemical sensors. For example... Figure 10 As shown, compared with other ions, the complex was found to have a better effect on Fe.3+ Ions exhibit high selectivity. Therefore, complexes can act as Fe... 3+ Selective ion sensing materials.

[0072] Test Example 3

[0073] The fluorescence detection performance of the novel zinc-based fluorescent probe compound containing pyridyl carboxylic acid type components was tested for 2,4,6-trinitrophenol (TNP): The finely ground sample (2 mg) was dispersed in N,N-dimethylformamide (DMF) solution (2 mL), and the fluorescence intensity of the complex was recorded by adding the same amount of different nitroaromatic explosives (NACs) (4-nitrotoluene (4-NT), 4-nitrophenol (4-NP) and 2,4,6-trinitrophenol (TNP)).

[0074] like Figure 11 As shown, various nitroaromatic explosives (NACs) quenched the fluorescence intensity of the complexes to varying degrees. However, TNP exhibited the most significant fluorescence quenching, with a quenching rate of approximately 93%. Inspired by these results, TNP titration experiments were performed on the complexes to further elucidate their sensitivity in detecting TNP. Figure 12 As shown, the fluorescence intensity of the complex in N,N-dimethylformamide (DMF) suspension gradually decreased with increasing TNP concentration, and the quenching efficiency reached over 90% when 100 μL of TNP was added. Furthermore, the quenching efficiency can also be expressed by the Stern-Volmer equation (I0 / I) = K sv ×[M] +1 Quantitative analysis was performed. The SV curve of TNP at low concentrations was nearly linear (e.g., Figure 13 As shown), K of TNP sv The calculated value is 9.60 × 10 4 M -1 Its value is greater than most reported MOF-based TNP sensors, and the calculated limit of detection (LOD) is 0.11 μM, which is comparable to previously reported MOF-based sensor materials. When other nitroaromatic explosives (NACs) solutions are added for fluorescence titration experiments, such as... Figure 14 As shown, the quenching effect of other NACs is not as obvious as that of TNP, which further indicates that the complex has the ability to selectively detect TNP.

[0075] Test Example 4

[0076] The novel zinc-based fluorescent probe compound containing pyridyl carboxylic acid type components was used to detect Fe. 3+The recyclability of ions and TNPs was tested: the complexes were recovered by centrifugation and thorough washing with N,N-dimethylformamide (DMF) after each fluorescence detection experiment.

[0077] like Figure 15 As shown, the fluorescence intensity and quenching efficiency of the recovered sample remained essentially stable throughout the four detection cycles, and the X-ray powder diffraction (PXRD) pattern of the sample showed no significant change after four detection cycles, indicating that the complex exhibits good stability. Therefore, this novel zinc-based fluorescent probe compound containing a pyridyl carboxylic acid component is applied to fluorescence detection. The complex can serve as a dual-function fluorescent sensor for highly sensitive and selective cyclic detection of Fe in N,N-dimethylformamide (DMF) solution. 3+ And 2,4,6-trinitrophenol (TNP).

[0078] In summary, the zinc-based fluorescent probe compound containing a pyridyl carboxylic acid type component, its preparation method, and its application, as described in the examples, exhibit good thermal stability, high pyrolysis temperature, and high luminescence intensity. It can serve as a bifunctional fluorescent sensor for highly sensitive and selective cyclic detection of Fe in N,N-dimethylformamide (DMF) solution. 3+ 2,4,6-Tinitrophenol (TNP) is a novel product synthesized in the laboratory, which has not been reported before. Its preparation method is simple, the synthesis time is short, the raw materials are readily available, and it has a wide range of applications.

[0079] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A zinc-based fluorescent probe containing a pyridyl carboxylic acid type component, characterized in that, The chemical formula is Zn(C) 22 H 14 N3O2)(CHO2)(H2O)·C3H7NO·3H2O; Zinc-based fluorescent probes containing pyridyl carboxylic acid type components belong to the monoclinic crystal system, space group 1. P 2 1 / c The unit cell parameters are a =7.2925(2)Å, b =26.6839(8)Å, c =12.8618(4)Å, α =90°, β =105.5770(10)°, γ =90°; The method for preparing the zinc-based fluorescent probe containing pyridine carboxylic acid type components includes the following steps: mixing zinc nitrate hexahydrate, 4-[4,2':6',4''-terpyridine]-4'-yl-benzoic acid, N,N-dimethylformamide and water, and carrying out a solvothermal reaction under closed conditions to obtain the zinc-based fluorescent probe containing pyridine carboxylic acid type components; The molar ratio of zinc nitrate hexahydrate to 4-[4,2':6',4''-terpyridine]-4'-ylbenzoic acid is 0.9~1:1; The volume ratio of N,N-dimethylformamide to water is 4.9~5:1; The ratio of zinc nitrate hexahydrate to N,N-dimethylformamide is 0.009~0.01 mmol: 0.5~0.6 mL; The solvothermal reaction is carried out at a temperature of 105~110℃ for a time of 46~48h. After the solvothermal reaction is completed, the temperature is reduced to 15-30℃ at a rate of 5-10℃ / h.

2. The method for preparing the zinc-based fluorescent probe containing a pyridyl carboxylic acid type component according to claim 1, characterized in that, Includes the following steps: Zinc nitrate hexahydrate, 4-[4,2':6',4''-terpyridine]-4'-ylbenzoic acid, N,N-dimethylformamide and water were mixed and subjected to a solvothermal reaction under closed conditions to obtain a zinc-based fluorescent probe containing a pyridine carboxylic acid component.

3. The preparation method according to claim 2, characterized in that, The molar ratio of zinc nitrate hexahydrate to 4-[4,2':6',4''-terpyridine]-4'-yl-benzoic acid is 0.9~1:

1.

4. The preparation method according to claim 2, characterized in that, The volume ratio of N,N-dimethylformamide to water is 4.9~5:

1.

5. The preparation method according to claim 2, characterized in that, The ratio of zinc nitrate hexahydrate to N,N-dimethylformamide is 0.009~0.01 mmol: 0.5~0.6 mL.

6. The preparation method according to claim 2, characterized in that, The solvothermal reaction is carried out at a temperature of 105~110℃ for a time of 46~48h.

7. The preparation method according to claim 2, characterized in that, After the solvothermal reaction is completed, the temperature is reduced to 15-30℃ at a rate of 5-10℃ / h.

8. A method for detecting Fe in N,N-dimethylformamide solution 3+ A bifunctional fluorescent sensor for 2,4,6-trinitrophenol, characterized in that, The zinc-based fluorescent probe including the pyridyl carboxylic acid type component as described in claim 1.

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