Zn-MOF fluorescence detection probe as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of chemical sensing, and particularly relates to a Zn-MOF fluorescence detection probe as well as a preparation method and application thereof. The structural unit of the Zn-MOF fluorescence detection probe is [Zn2 (TPB) (BPDC-(OH) 2) 2]. (DMF). (H2O), wherein the BPDC-(OH) 2 is a 2, 5-dihydroxy terephthalic acid anion; the fluorescence detection probe belongs to a monoclinic system, the space group is C2 / c, and the Zn-MOF fluorescence detection probe has the characteristics of good selectivity, high sensitivity, high response speed and the like. The preparation method comprises the following steps: mixing 2, 5-dihydroxyterephthalic acid, 1, 2, 4, 5-tetra (4-pyridyl) benzene, zinc nitrate, N, N-dimethylformamide and deionized water, carrying out a heating reaction, filtering, and drying to obtain the Zn-MOF fluorescence detection probe. The preparation method has the advantages of easily available raw materials, simple operation and the like. The Zn-MOF fluorescence detection probe can be used for detecting sulfasalazine, realizes visual identification of SSZ according to the change of fluorescence intensity of the probe, can qualitatively determine SSZ in real time through a portable fluorescent lamp, and has important application value.

Description

Technical Field

[0001] The present invention belongs to the technical field of chemical sensing, and in particular relates to a Zn-MOF fluorescent detection probe and a preparation method and application thereof. Background Art

[0002] The information disclosed in this background section is intended to enhance understanding of the overall background of the invention and should not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0003] Sulfasalazine, also known as sulfasalazine (SSZ), is a widely used antibiotic drug, mainly used to treat inflammatory bowel disease, ankylosing spondylitis and other diseases. However, the extensive use of sulfasalazine in animal husbandry and agriculture has led to a large amount of residues in animal food. In addition, sulfasalazine can also enter the soil and water through animal excrement. These residual sulfasalazine will pollute the soil and water quality, thereby threatening human health.

[0004] However, so far, no relevant detection of SSZ has been reported in instrumental detection methods, so there is an urgent need to develop a rapid, simple and sensitive detection method to monitor the residues of sulfasalazine. The fluorescent probe detection method has the characteristics of rapid response, simple operation and specific selection, which is more in line with the needs of real-time, efficient and highly selective detection. Summary of the invention

[0005] In view of the deficiencies in the prior art, the first object of the present invention is to provide a Zn-MOF fluorescent detection probe, which has the characteristics of good selectivity, high sensitivity and fast response speed.

[0006] The second object of the present invention is to provide a method for preparing the above-mentioned Zn-MOF fluorescent detection probe, which has the advantages of easy availability of raw materials, simple operation and low cost.

[0007] The third object of the present invention is to provide an application of the above-mentioned Zn-MOF fluorescence detection probe, wherein the Zn-MOF fluorescence detection probe can be used for fluorescence detection of SSZ.

[0008] To achieve the above object, the present invention adopts the following technical solutions: A Zn-MOF fluorescent detection probe, wherein the structural unit of the Zn-MOF fluorescent detection probe is [Zn 2 (TPB)(BPDC-(OH) 2 ) 2 ]·(DMF)·(H 2O); among them, BPDC-(OH) 2 represents 2,5-dihydroxyterephthalic acid divalent anion; the Zn-MOF fluorescent detection probe belongs to the monoclinic system, and the space group is C 2 / c .

[0009] Furthermore, the unit cell parameters of the Zn-MOF fluorescence detection probe are a (Å) = 20.6335(4), b (Å) =12.43343(19), c (Å) = 22.1023(4), , , , the unit cell volume is V( Å 3 ) = 5180.47(16).

[0010] Furthermore, the minimum asymmetric unit structure of the Zn-MOF fluorescent detection probe includes two Zn(II) atoms, a TPB ligand, two different BPDC-(OH) 2 2- anion, a DMF molecule and a water molecule, the central Zn1(II) ion is pentacoordinated with a trigonal bipyramidal coordination geometry; the Zn1(II) ion is bound to one of the BPDC-(OH) 2 2- The two carboxylic acid oxygen atoms (O1, O2) of the ligand (Zn1-O1 = 2.0975(16) Å and Zn1-O2 = 2.2600(14) Å) are coordinated, and the other BPDC-(OH) 2 2- The coordination is formed by one carboxylic acid oxygen atom (O5) of the ligand (Zn1-O5 = 1.9976(14) Å) and two nitrogen atoms (N1, N2) of the TPB ligand (Zn1-N1 = 2.0490(15) Å and Zn1-N2 = 2.0779(13) Å).

[0011] The preparation method of the above-mentioned Zn-MOF fluorescent detection probe comprises the following steps: 2,5-dihydroxyterephthalic acid (H 2 BPDC-(OH) 2 , DDA), 1,2,4,5-tetra(4-pyridyl)benzene (TPB), zinc nitrate, N, N-dimethylformamide (DMF) and deionized water are mixed, heated to react, filtered and dried to obtain the Zn-MOF fluorescent detection probe.

[0012] Furthermore, the mass volume ratio of the 2,5-dihydroxyterephthalic acid, 1,2,4,5-tetrakis(4-pyridyl)benzene, zinc nitrate, N, N-dimethylformamide and deionized water is (3.5-4) mg: (4.5-5) mg: (16-20) mg: (4-5) mL: (4-5) mL.

[0013] Furthermore, the heating reaction is carried out at a temperature of 90-100° C. and for a time of 20-30 h.

[0014] Furthermore, the heating reaction is carried out at a temperature of 90-100° C. and for 24 h.

[0015] Furthermore, after the heating reaction, the temperature needs to be cooled to room temperature.

[0016] Application of the above Zn-MOF fluorescent detection probe, the Zn-MOF fluorescent detection probe can be used for the detection of SSZ.

[0017] Beneficial effects: The present invention provides a novel Zn-MOF fluorescent detection probe, which has the characteristics of good selectivity, high sensitivity and fast response speed, and the preparation method of the Zn-MOF fluorescent detection probe has the advantages of easy raw materials, simple operation and low cost. The Zn-MOF fluorescent detection probe can visually identify SSZ in real time according to the change of the probe fluorescence intensity, and can quantitatively determine the SSZ concentration by using a fluorescence spectrometer, and the detection line can reach 100 n moL, providing a new method for the detection of sulfasalazine. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. The embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein: Figure 1 is the asymmetric unit structure diagram and two-dimensional layered structure diagram of the Zn-MOF fluorescent detection probe prepared in Example 1, Figure 1 (a) is the asymmetric unit structure diagram. Figure 1 (b) is a two-dimensional layered structure diagram; Figure 2 The one-dimensional channel structure diagram and the network triple interlaced structure diagram of the Zn-MOF fluorescent detection probe prepared in Example 1 are shown in FIG. Figure 2 (a) is a one-dimensional channel diagram along the a-axis, Figure 2 (b) is the one-dimensional channel structure diagram along the c-axis. Figure 2 (c) is a diagram of the triple interlaced structure of the network; Figure 3is the powder diffraction spectrum of the Zn-MOF fluorescent detection probe prepared in Example 1; Figure 4 It is the fluorescence spectrum of the Zn-MOF fluorescence detection probe and the ligand DDA prepared in Example 1; Figure 5 This is a test result diagram of the recognition selectivity of the Zn-MOF fluorescent detection probe prepared in Example 1 for different analytes; Figure 6 This is a test diagram of interference selectivity of the Zn-MOF fluorescence detection probe prepared in Example 1; Figure 7 This is a test graph of the fluorescence response time of the Zn-MOF fluorescence detection probe prepared in Example 1 to detect SSZ; Figure 8 This is a test graph of the response of the Zn-MOF fluorescence detection probe prepared in Example 1 to different concentrations of SSZ; Fig. 9 This is a linear fitting graph of the fluorescence response of the Zn-MOF fluorescence detection probe prepared in Example 1 to different concentrations of SSZ. DETAILED DESCRIPTION

[0019] The following description further describes the specific details of the present invention for a full understanding of the present invention. The terms used in the description of the present invention are only used to illustrate the advantages and features of the present invention and are not intended to limit the present invention.

[0020] Unless otherwise defined, all professional and scientific terms used in the present invention have the same meanings as those understood by technicians in the technical field of the present invention. Unless otherwise specified, the drugs or reagents used in the present invention are used in accordance with the product instructions or the conventional methods of use in the field. The technical solution of the present invention is further described according to the drawings and specific embodiments of the specification.

[0021] Example 1 (1) Add 18 mg of zinc nitrate, 4 mg of 2,5-dihydroxyterephthalic acid, 5 mg of 1,2,4,5-tetrakis(4-pyridyl)benzene, 4 mL of N, N-dimethylformamide and 4 mL of deionized water into a 25 mL hydrothermal synthesis reactor and stir well to obtain a mixed solution; (2) Encapsulate the mixed solution obtained in step (1) and place it in a reactor, then place the reactor in an oven and heat it to 90° C., and allow the mixed solution to react in the reactor for 24 h; (3) The reactor was taken out of the oven, the temperature was lowered to room temperature, the mixed solution after the reaction was taken out of the reactor, filtered and dried to obtain a Zn-MOF fluorescent detection probe, which was recorded as MOF-1.

[0022] The structural characterization of the Zn-MOF fluorescent probe is as follows: The Zn-MOF fluorescent detection probe is a monoclinic system. C 2 / c Space group. Figure 1 It is the asymmetric unit structure diagram and the two-dimensional layered structure diagram of the Zn-MOF fluorescence detection probe prepared in Example 1; Figure 1 (a) is the asymmetric unit structure diagram of the Zn-MOF fluorescent detection probe prepared in Example 1. The results show that the asymmetric unit of the Zn-MOF fluorescent detection probe includes two Zn(II) atoms, a TPB ligand, and two different BPDC-(OH) 2 2- anion, a DMF molecule and a water molecule, the central Zn1(II) ion is pentacoordinated with a trigonal bipyramidal coordination geometry; the Zn1(II) ion is bound to a BPDC-(OH) 2 2- The two carboxylic acid oxygen atoms (O1, O2) of the ligand (Zn1-O1 = 2.0975(16) Å and Zn1-O2 = 2.2600(14) Å) and the other BPDC-(OH) 2 2- Coordination is formed by one carboxylic acid oxygen atom (O5) of the ligand (Zn1-O5 = 1.9976(14) Å) and two nitrogen atoms (N1, N2) of two different TPB ligands (Zn1-N1 = 2.0490(15) Å and Zn1-N2 = 2.0779(13) Å); Figure 1 (b) is a two-dimensional layered structure diagram of the Zn-MOF fluorescent detection probe along the ac plane. The results show that in the Zn-MOF fluorescent detection probe, each TPB ligand is connected to four Zn(II) ions through a nitrogen atom to form a one-dimensional zigzag chain. BPDC-(OH) 2 2- The carboxylic acid oxygen atoms of the ligands are connected to these one-dimensional chains in a monodentate coordination manner to form a two-dimensional layered structure on the ac plane.

[0023] Figure 2 The one-dimensional channel structure diagram and the network triple interlaced structure diagram of the Zn-MOF fluorescent detection probe prepared in Example 1 are shown in FIG. Figure 2 (a) Shows the three-dimensional layered structure of the Zn-MOF fluorescent detection probe, with a one-dimensional channel along the a-axis. Figure 2 (b) Shows the three-dimensional layered structure of the Zn-MOF fluorescence detection probe, which has a one-dimensional channel structure along the c-axis direction; Figure 2(c) Shows the triple interpenetrating network structure of Zn-MOF; the pore size of the three-dimensional framework along the a-axis is 10.48 Å×14.40 Å, and the pore size along the c-axis is 13.53 Å×8.08 Å.

[0024] Example 2 (1) Add 20 mg of zinc nitrate, 3.5 mg of 2,5-dihydroxyterephthalic acid, 5 mg of 1,2,4,5-tetrakis(4-pyridyl)benzene, 5 mL of N, N-dimethylformamide and 5 mL of deionized water into a 25 mL hydrothermal synthesis reactor and stir well to obtain a mixed solution; (2) Encapsulate the mixed solution obtained in step (1) and place it in a reactor, then place the reactor in an oven and heat it to 100° C., and allow the mixed solution to react in the reactor for 24 h; (3) The reactor was taken out of the oven, the temperature was lowered to room temperature, the mixed solution after the reaction was taken out of the reactor, filtered and dried to obtain a Zn-MOF fluorescent detection probe.

[0025] Example 3 (1) Add 16 mg of zinc nitrate, 4.0 mg of 2,5-dihydroxyterephthalic acid, 4.5 mg of 1,2,4,5-tetrakis(4-pyridyl)benzene, 5 mL of N, N-dimethylformamide and 5 mL of deionized water into a 25 mL hydrothermal synthesis reactor and stir well to obtain a mixed solution; (2) Encapsulate the mixed solution obtained in step (1) and place it in a reactor, then place the reactor in an oven and heat it to 100° C., and allow the mixed solution to react in the reactor for 24 h; (3) The reactor was taken out of the oven, the temperature was lowered to room temperature, the mixed solution after the reaction was taken out of the reactor, filtered and dried to obtain a Zn-MOF fluorescent detection probe.

[0026] Performance Testing (1) Zn-MOF fluorescence detection probe powder diffraction test (PXRD): The Zn-MOF fluorescent detection probe prepared in Example 1 was tested on a Bruker D8 ADVANCE X-Ray Diffractometer at room temperature. The spectrum is shown in FIG. Figure 3 The results showed that the main diffraction peaks of the test spectrum were consistent with the simulated peaks based on crystal data, indicating that the Zn-MOF fluorescent detection probe had good purity. Figure 3The horizontal coordinate 2 theta / degree is the X-ray diffractometer scanning the entire diffraction area at an angle of 2θ, which exists as the horizontal coordinate of the X-ray diffraction spectrum, and the intensity of the diffraction peak at different diffraction angles is the vertical coordinate.

[0027] (2) Fluorescence test of Zn-MOF SSZ fluorescence detection probe: The Zn-MOF fluorescent detection probe (MOF-1) prepared in Example 1 and the synthetic raw material BPDC-(OH) 2 The fluorescence spectrophotometer was used to measure the fluorescence at room temperature with an excitation wavelength of 350 nm. Figure 4 , Figure 4 DDA in BPDC-(OH) 2 .Depend on Figure 4 It can be seen that the Zn-MOF fluorescent probe prepared above has one fluorescence emission peak at 460 nm.

[0028] (3) The Zn-MOF fluorescence detection probe prepared in Example 1 is used for fluorescence detection of SSZ. Usually, the probe molecules can be dispersed in dimethyl sulfoxide solvent at room temperature for testing. In order to study the specific recognition effect of the probe molecule prepared by the present invention on the SSZ molecule, a Zn-MOF fluorescence detection probe solution prepared in Example 1 with a concentration of 1 mg / mL was prepared using dimethyl sulfoxide as a solvent; 1 mM dimethyl sulfoxide solutions of different analytes were prepared respectively, and the different analytes were: STZ (sulfathiazole); SPR (sulfapyridine); PST (phthaleinsulfathiazole); SMD (sulfa-5-methoxazole); SDA (silver methoxazole); SIZ (sulfisoxazole); SMZ (sulfamethoxazole); SM2 (sulfadimethoxine); SG (sulfaguanidine); NSL (sulfacetamide); SDZ (sulfadiazine); SSZ (sulfasalazine); SDT (sulfadimethoxine); DSN (3,5-dichlorosulfonamide); BBS (3-bromobenzenesulfonamide); PTS (p-toluenesulfonamide); CPFX (ciprofloxacin); MDZ (metronidazole); CAP (chloramphenicol).

[0029] Dimethyl sulfoxide was used as a solvent to prepare a 1 mg / mL Zn-MOF fluorescent detection probe suspension prepared in Example 1, and then 50 μM dimethyl sulfoxide solutions of different analytes were added to 2 mL of the fluorescent detection probe suspension, respectively. The different analytes were: STZ (sulfathiazole); SPR (sulfapyridine); PST (phthaleinsulfathiazole); SMD (sulfa-5-methoxazole); SDA (silver methoxazole); SIZ (sulfisoxazole); SMZ (sulfamethoxazole); SM2 (sulfadimethoxine); SG (sulfaguanidine); NSL (sulfacetamide); SDZ (sulfadiazine); SSZ (sulfasalazine); SDT (sulfadimethoxine); DSN (3,5-dichlorosulfonamide); BBS (3-bromobenzenesulfonamide); PTS (p-toluenesulfonamide); CPFX (ciprofloxacin); MDZ (metronidazole); CAP (chloramphenicol). The relative fluorescence intensity of the probe suspension before and after adding different organic molecules was measured. Figure 5 As shown, the fluorescence of the fluorescent probe solution with only SSZ significantly decreased. Compared with SSZ, other structural analogs and probe molecules had no obvious effect. The results showed that the fluorescent detection probe molecules prepared by the present invention can specifically recognize and detect SSZ.

[0030] (4) Detecting the response of the Zn-MOF probe prepared in Example 1 to the two sets of analytes: A Zn-MOF probe suspension with a concentration of 1 mg / mL was prepared using dimethyl sulfoxide as the solvent. A 50 μM SSZ dimethyl sulfoxide solution was then added to 2 mL of the probe suspension. The dimethyl sulfoxide solutions of the following analytes were then added: STZ (sulfathiazole); SPR (sulfapyridine); PST (phthaleinsulfathiazole); SMD (sulfa-5-methoxypyrimidine); SDA (silver methoxypyrimidine); SIZ (sulfisoxazole); SMZ (sulfamethoxazole); SM2 (sulfadimethoxine); SG (sulfaguanidine); NSL (sulfacetamide); SDZ (sulfadiazine); SSZ (sulfasalazine); SDT (sulfadimethoxine); DSN (3,5-dichlorosulfonamide); BBS (3-bromobenzenesulfonamide); PTS (p-toluenesulfonamide); CPFX (ciprofloxacin); MDZ (metronidazole); CAP (chloramphenicol). The concentration of the dimethyl sulfoxide solution of each analyte was 50 μM. μM. Determine the relative fluorescence intensity of the fluorescent detection probe suspension before and after adding the analyte. The results are as follows Figure 6 As shown. Figure 6 It can be seen that the addition of other analytes does not affect the recognition of SSZ by the probe. The experimental results obtained in this example show that the probe molecule can specifically recognize and detect SSZ.

[0031] (5) Detecting the response time of the Zn-MOF probe prepared in Example 1 to different concentrations of SSZ: A 1 mg / mL Zn-MOF probe suspension was prepared using dimethyl sulfoxide as solvent, and a 50 μM SSZ dimethyl sulfoxide solution was added to 2 mL of the above probe suspension. The probe fluorescence intensity was recorded every 30 s. The results are shown in Figure 2. Figure 7 As shown, Figure 7 This is a test chart of the fluorescence response time of SSZ using a 1 mg / mL Zn-MOF fluorescent probe system; the horizontal axis is the time of adding SSZ, and the vertical axis is the relative fluorescence intensity. Figure 7 It can be seen that after adding SSZ, it has fully responded within 30 seconds. The results show that the fluorescent detection probe molecules prepared by the present invention can quickly react with SSZ to give a change in fluorescent signal, and can be used for real-time monitoring of SSZ.

[0032] (6) Detecting the response of the Zn-MOF probe prepared in Example 1 to different concentrations of SSZ: A Zn-MOF probe suspension with a concentration of 1 mg / mL was prepared using dimethyl sulfoxide as solvent, and 0.1-250 μM SSZ was added to 2 mL of the above probe suspension. The relative fluorescence intensity of the probe suspension before and after the addition of the analyte was measured. The results are shown in Figure 2. Figure 8 As shown, Figure 8 This is a test chart of the response of 1 mg / mL Zn-MOF fluorescent probe system to different concentrations of SSZ. The results show that the fluorescence intensity of the Zn-MOF probe decreases rapidly with the increase of SSZ concentration, and the lowest detection concentration is below 200 nM, indicating that the fluorescence intensity of the fluorescent detection probe prepared by the present invention responds well to the increase of SSZ concentration.

[0033] (7) Linear fitting of the fluorescence response test results of the Zn-MOF probe prepared in Example 1 to different concentrations of SSZ: A Zn-MOF probe suspension with a concentration of 1 mg / mL was prepared using dimethyl sulfoxide as solvent, and 0.1-250 μM SSZ was added to 2 mL of the above probe suspension. The relative fluorescence intensity of the probe suspension before and after the addition of the analyte was measured. Figure 8 The fluorescence intensity was plotted against the SSZ concentration and a linear fit was performed. Fig. 9 , Fig. 9 is the linear fitting diagram of the fluorescence response of 1 mg / mL Zn-MOF fluorescent probe system to different concentrations of SSZ. Fig. 9 It can be seen that in the range of SSZ concentration of 0.1-5 μM, the probe fluorescence intensity shows a good linear relationship with SSZ concentration. The nonlinear equation is: (R 2 =0.998). The above experimental results show that the probe has the potential for quantitative detection of SSZ.

[0034] In summary, the Zn-MOF fluorescence detection probe of the present invention is characterized in that SSZ can be visually identified according to the change in the fluorescence intensity of the probe; and SSZ can be qualitatively determined in real time using a portable fluorescence spectrometer.

[0035] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0036] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A Zn-MOF fluorescence detection probe, It is characterized in that The structural unit of the Zn-MOF fluorescent detection probe is [Zn 2 (TPB)(BPDC-(OH) 2 ) 2 ]·(DMF)·(H 2 O); BPDC- (OH) 2 represents 2,5-dihydroxyterephthalic acid anion; the Zn-MOF fluorescent detection probe belongs to the monoclinic system, and the space group is C 2 / c .

2. The Zn-MOF fluorescent detection probe according to claim 1, It is characterized in that 3. The method for preparing the Zn-MOF fluorescent detection probe according to claim 1 or 2, It is characterized in that The preparation method adopts the following steps: 2,5-dihydroxyterephthalic acid, 1,2,4,5-tetra(4-pyridyl)benzene, zinc nitrate, N,N-dimethylformamide and deionized water are mixed, heated for reaction, filtered and dried to obtain the Zn-MOF fluorescent detection probe.

4. The preparation method according to claim 3, It is characterized in that The mass volume ratio of the 2,5-dihydroxyterephthalic acid, 1,2,4,5-tetra(4-pyridyl)benzene, zinc nitrate, N,N-dimethylformamide and deionized water is (3.5-4) mg: (4.5-5) mg: (16-20) mg: (4-5) mL: (4-5) mL.

5. The preparation method according to claim 3, It is characterized in that The heating reaction temperature is 90-100° C. and the time is 20-30 h.

6. The preparation method according to claim 5, It is characterized in that The heating reaction time is 24 h.

7. The preparation method according to claim 3, It is characterized in that After the heating reaction, the temperature needs to be lowered to room temperature.

8. Use of the Zn-MOF fluorescent detection probe according to claim 1 or 2 and / or the Zn-MOF fluorescent detection probe prepared by the method according to any one of claims 3 to 7, It is characterized in that The Zn-MOF fluorescent detection probe is used for the detection of SSZ.

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