Zinc coordination polymer, preparation method thereof, and application in detecting ceftazidime

Abstract

The present invention discloses a zinc coordination polymer, a preparation method thereof and an application thereof in detecting ceftazidime. The coordination polymer chemical formula is {[Zn(fipa)(3-bpdb)2} n , where fipa is a completely deprotonated organic bridging ligand 5-(furan-2-yl)isophthalate, 3-bpdb is an auxiliary ligand 1,4-bis(3-pyridyl)-2,3-dichloro-1,3-butadiene, n represents the degree of polymerization, which is a natural number; each four-coordinated metal Zn is at the center of a distorted tetrahedral geometry. 2+ The zinc coordination polymer is linked to two 1,4-bis(3-pyridyl)-2,3-dichloro-1,3-butadiene chains to form a V-shaped structure. This structure is then connected to a long-range, ordered one-dimensional chain structure along the a-axis by a deprotonated 5-(furan-2-yl)isophthalic acid group. Adjacent chains are connected by abundant hydrogen bonds (C−H···O) and π···π stacking interactions to form a three-dimensional supramolecular framework. The zinc coordination polymer can detect ceftazidime in water in a relatively short time, with high sensitivity, strong selectivity, and good thermal and water stability. It has great potential for the detection of ceftazidime antibiotics.

Description

Technical Field

[0001] The invention belongs to the technical field of metal organic complexes, and particularly relates to a zinc coordination polymer, a preparation method thereof, and an application thereof in detecting ceftazidime. Background Art

[0002] Antibiotics are widely used in medicine, agriculture, and livestock farming due to their bactericidal, antibacterial, anti-inflammatory, antiviral, and infection-preventing effects. In the medical field, antibiotics are often used to treat infectious diseases of the genitourinary and respiratory systems, prevent surgical infections, and treat complicated abdominal infections. In animal husbandry, antibiotics are often added to feed to prevent and treat animal diseases caused by infectious pathogens, improve animal survival rates and health levels, and improve animal growth efficiency and weight gain rates. However, long-term use or even abuse of antibiotics can easily cause adverse allergic reactions, gastrointestinal disorders, liver toxicity, dysbacteriosis, damage to the nervous system, decreased immunity, and bacterial resistance to antibiotics. Currently, antibiotics are becoming a worrying emerging pollutant in the environment.

[0003] Currently, commonly used methods for antibiotic detection include high-performance liquid chromatography, gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry, enzyme-linked immunosorbent assay (ELISA), capillary electrophoresis, electrochemical methods, and fluorescence spectroscopy. Fluorescence spectroscopy has attracted considerable attention due to its convenience, efficiency, sensitivity, low detection limit, and visualization.

[0004] Coordination polymers are crystalline porous materials composed of organic ligands and metal ions or clusters. They feature high porosity, excellent stability, and an increased surface area. They are currently widely used in catalysis, adsorption and separation, drug storage, and sensing. Due to the diverse nature of the metal ions and organic ligands, coordination polymers have a wide range of structural variations. Some coordination polymers possess unique luminescence properties, with diverse and adjustable emission patterns. They can be used as fluorescent sensors to detect metal ions, small organic molecules, and nitro-explosives.

[0005] Although there are reports on the use of coordination polymers for antibiotic detection, most of them are used to detect nitrofurans or nitroimidazoles, and there are still few reports on their use for detecting cephalosporins. In addition, most coordination polymers have poor water stability and can only be used in organic solvent systems. Therefore, it is of great significance to prepare water-stable and highly sensitive coordination polymers for detecting ceftazidime. Summary of the Invention

[0006] The first object of the present invention is to provide a zinc coordination polymer, the second object of the present invention is to provide a method for preparing the zinc coordination polymer, and the third object of the present invention is to provide applications of the zinc coordination polymer.

[0007] The first object of the present invention is achieved by providing a zinc coordination polymer having the chemical formula {[Zn(fipa)(3-bpdb)2} n , where fipa is the completely deprotonated organic bridging ligand 5-(furan-2-yl)isophthalate, 3-bpdb is the auxiliary ligand 1, 4-bis(3-pyridyl)-2, 3-dichloro-1, 3-butadiene, and n represents the degree of polymerization, a natural number. Each four-coordinated metal zinc ion at the center of a distorted tetrahedral geometry connects to two 1, 4-bis(3-pyridyl)-2, 3-dichloro-1, 3-butadienes to form a V-shaped structure, which is then connected by the deprotonated 5-(furan-2-yl)isophthalate to form a long-range ordered one-dimensional chain structure along the a-axis. Adjacent chains are connected by abundant hydrogen bonds (C−H···O) and π···π stacking interactions to form a three-dimensional supramolecular framework.

[0008] The second object of the present invention is achieved by the method for preparing the zinc coordination polymer, which is achieved by the following steps:

[0009] 1) Add the organic ligand 5-(furan-2-yl)isophthalic acid and 1,4-bis(3-pyridyl)-2,3-dichloro-1,3-butadiene to a mixed solvent of N,N-dimethylformamide and water and sonicate for 10-20 minutes until completely dissolved;

[0010] 2) Add 0.5 mol / L zinc nitrate solution and continue ultrasonication for 10-20 minutes to mix thoroughly. Seal the mixture and place in an oven. React at 100-120°C for 48-96 hours. Slowly cool to room temperature to obtain colorless block crystals.

[0011] 3) Filtering the colorless block crystals, washing with N, N-dimethylformamide, and drying for 1-2 days to obtain the target coordination polymer.

[0012] Wherein, the organic ligands 5-(furan-2-yl)isophthalic acid and 1,4-bis(3-pyridyl)-2,3-dichloro-1,3-butadiene in step 1) have the structural formulas shown in Formula (I) and Formula (II), respectively:

[0013]

[0014] (I)

[0015]

[0016] (II)

[0017] The third object of the present invention is achieved by using the zinc coordination polymer as a fluorescent sensor in detecting ceftazidime, wherein the zinc coordination polymer is immersed in deionized water, and then a methanol solution of the antibiotic to be detected is added, and detection is performed using liquid fluorescence.

[0018] The beneficial effects of the present invention are:

[0019] 1) The zinc coordination polymer provided by the present invention can achieve specific fluorescent recognition of ceftazidime with good selectivity and is not interfered with by antibiotics such as cefoperazone, sulfamethoxazole, thiamphenicol, lincomycin, vancomycin, and amoxicillin. In the presence of multiple antibiotics, the zinc coordination polymer can still achieve fluorescent detection of ceftazidime.

[0020] 2) Experimental results show that the zinc coordination polymer provided by the present invention has a -1 It showed high sensitive detection performance for ceftazidime at low concentrations, and its fluorescence intensity was I 0 / I It has a good linear relationship with the concentration of ceftazidime, and responds quickly to ceftazidime with a response time of 60 seconds; ultimately, the fluorescence intensity of the coordination polymer can achieve efficient detection of low-concentration ceftazidime.

[0021] 3) The zinc coordination polymer provided by this invention has excellent thermal stability, with its structure decomposing at 345°C. It also has good water stability, remaining stable in water for long periods of time. After immersion in water for seven days, the powder diffraction pattern of the material was highly consistent with that before immersion, ensuring that the material can detect ceftazidime in aqueous solution.

[0022] 4) The zinc coordination polymer provided by the present invention has a simple preparation method, a short preparation cycle, and a high yield, and provides an ideal material for the selective detection of antibiotics. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a diagram of the coordination environment of the metal and ligand in the zinc coordination polymer of the present invention;

[0024] Figure 2 is a one-dimensional chain structure diagram of the zinc coordination polymer of the present invention;

[0025] Figure 3 This is a two-dimensional layered structure diagram formed by hydrogen bonding of the zinc coordination polymer of the present invention;

[0026] Figure 4 is a three-dimensional supramolecular structure diagram of the zinc coordination polymer of the present invention;

[0027] Figure 5The fluorescence response spectra of the zinc coordination polymer of the present invention to different antibiotics;

[0028] Figure 6 This is a schematic diagram of the anti-interference detection of ceftazidime by the zinc coordination polymer of the present invention;

[0029] Figure 7 This is a linear graph of the zinc coordination polymer of the present invention at low ceftazidime concentration. DETAILED DESCRIPTION

[0030] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments, but the present invention is not limited in any way. Any changes or improvements made based on the teachings of the present invention fall within the scope of protection of the present invention.

[0031] The present invention provides a zinc coordination polymer, the chemical formula of which is {[Zn(fipa)(3-bpdb)2} n , where fipa is the completely deprotonated organic bridging ligand 5-(furan-2-yl)isophthalate, 3-bpdb is the auxiliary ligand 1, 4-bis(3-pyridyl)-2, 3-dichloro-1, 3-butadiene, and n represents the degree of polymerization, a natural number. Each four-coordinated metal zinc ion at the center of a distorted tetrahedral geometry connects to two 1, 4-bis(3-pyridyl)-2, 3-dichloro-1, 3-butadienes to form a V-shaped structure, which is then connected by the deprotonated 5-(furan-2-yl)isophthalate to form a long-range ordered one-dimensional chain structure along the a-axis. Adjacent chains are connected by abundant hydrogen bonds (C−H···O) and π···π stacking interactions to form a three-dimensional supramolecular framework.

[0032] The coordination polymer belongs to the triclinic system, P -1 space group, unit cell parameters: a=10.1782 Å, b=10.4452 Å, c=15.3514 Å, α=86.4798°, β=88.5248°, γ=88.6987°, unit cell volume V=1628.0(6) Å 3 .

[0033] The present invention also provides a method for preparing the zinc coordination polymer, which is achieved by the following steps:

[0034] 1) Add the organic ligand 5-(furan-2-yl)isophthalic acid and 1,4-bis(3-pyridyl)-2,3-dichloro-1,3-butadiene to a mixed solvent of N,N-dimethylformamide and water and sonicate for 10-20 minutes until completely dissolved;

[0035] 2) Add 0.5 mol / L zinc nitrate solution and continue ultrasonication for 10-20 minutes to mix thoroughly. Seal the mixture and place in an oven. React at 80-120°C for 48-96 hours. Then slowly cool to room temperature at a rate of 10°C / hour to obtain colorless block crystals.

[0036] 3) Filtering the colorless block crystals, washing with N, N-dimethylformamide, and drying for 1-2 days to obtain the target coordination polymer.

[0037] Wherein, the organic ligands 5-(furan-2-yl)isophthalic acid and 1,4-bis(3-pyridyl)-2,3-dichloro-1,3-butadiene in step 1) have the structural formulas shown in Formula (I) and Formula (II), respectively:

[0038]

[0039] (I) (II)

[0040] The molar ratio of the 5-(furan-2-yl)isophthalic acid, 1,4-bis(3-pyridyl)-2,3-dichloro-1,3-butadiene and zinc nitrate hexahydrate is 1:1:1-2.

[0041] In the step 1), the volume ratio of N, N-dimethylformamide to water is 1:1.

[0042] In step 2), the cooling rate is 10°C / h.

[0043] The present invention further provides an application of the zinc coordination polymer, specifically an application as a fluorescent sensor in detecting ceftazidime, wherein the zinc coordination polymer is immersed in deionized water, and then a methanol solution of the antibiotic to be detected is added, and detection is performed using liquid fluorescence.

[0044] Example 1

[0045] 1) Dissolve 1.48 g of zinc nitrate hexahydrate in 10 mL of deionized water to prepare a 0.5 mol / L zinc nitrate solution.

[0046] 2) Place the organic ligand 5-(furan-2-yl)isophthalic acid (58 mg) and 1,4-bis(3-pyridyl)-2,3-dichloro-1,3-butadiene (53 mg) in a 10 mL glass vial. Add 2 mL of N,N-dimethylformamide and 2 mL of deionized water. Ultrasonicate for 10-20 min until completely dissolved.

[0047] 3) Add 1 mL of the zinc nitrate solution from step 1) dropwise to the ligand solution from step 2) and sonicate for 10-20 min to mix thoroughly. Seal the mixture and place in a 100°C oven for a constant temperature solvothermal reaction for 96 hours. Slowly cool the mixture to room temperature at a rate of 10°C / h to obtain colorless blocky crystals with a yield of approximately 64.5%.

[0048] 4) The colorless block crystals obtained in step 3) were filtered, washed with N, N-dimethylformamide, and dried for 1-2 days to obtain the target zinc coordination polymer. The chemical formula of the zinc coordination polymer is {[Zn(fipa)(3-bpdb)2} n , in which the completely deprotonated organic bridging ligand 5-(furan-2-yl)isophthalate (fipa) is the main ligand and 1, 4-bis(3-pyridyl)-2, 3-dichloro-1, 3-butadiene (3-bpdb) is the auxiliary ligand. Figure 1 As shown, each four-coordinated metal zinc ion is at the center of a deformed tetrahedral geometry, connected to two 1, 4-bis(3-pyridyl)-2, 3-dichloro-1, 3-butadiene to form a V-shaped structure, and then connected through the carboxyl groups at both ends of the main ligand to form a V-shaped structure as shown in FIG. Figure 2 The one-dimensional chain structure extending along the a-axis is shown. Figure 3 As shown in the figure, adjacent one-dimensional chains are extended into two-dimensional layers through abundant hydrogen bonds (C−H···O). Figure 4 The two-dimensional layers shown are connected to form a three-dimensional supramolecular framework through π···π stacking.

[0049] Example 2

[0050] 1) Dissolve 1.48 g of zinc nitrate hexahydrate in 10 mL of deionized water to prepare a 0.5 mol / L zinc nitrate solution.

[0051] 2) Place the organic ligand 5-(furan-2-yl)isophthalic acid (58 mg) and 1,4-bis(3-pyridyl)-2,3-dichloro-1,3-butadiene (53 mg) in a 10 mL glass vial. Add 2 mL of N,N-dimethylformamide and 2 mL of deionized water. Ultrasonicate for 10-20 min until completely dissolved.

[0052] 3) Add 0.5 mL of the zinc nitrate solution from step 1) dropwise to the ligand solution from step 2) and sonicate for 10-20 min to mix thoroughly. Seal the mixture and place in a 120°C oven for a constant temperature solvothermal reaction for 48 hours. Slowly cool the mixture to room temperature at a rate of 10°C / h to obtain colorless blocky crystals with a yield of approximately 56.2%.

[0053] 4) The colorless block crystals obtained in step 3) are filtered, washed with N, N-dimethylformamide, and dried for 1-2 days to obtain the target zinc coordination polymer.

[0054] Example 3

[0055] 1) Dissolve 1.48 g of zinc nitrate hexahydrate in 10 mL of deionized water to prepare a 0.5 mol / L zinc nitrate solution.

[0056] 2) Place the organic ligand 5-(furan-2-yl)isophthalic acid (58 mg) and 1,4-bis(3-pyridyl)-2,3-dichloro-1,3-butadiene (53 mg) in a 10 mL glass vial. Add 2 mL of N,N-dimethylformamide and 2 mL of deionized water. Ultrasonicate for 10-20 min until completely dissolved.

[0057] 3) Add 1 mL of the zinc nitrate solution from step 1) dropwise to the ligand solution from step 2) and sonicate for 10-20 min to mix thoroughly. Seal the mixture and place in an 80°C oven for a constant temperature solvothermal reaction for 96 hours. Slowly cool the mixture to room temperature at a rate of 10°C / h to obtain colorless blocky crystals with a yield of approximately 53.7%.

[0058] 4) The colorless block crystals obtained in step 3) are filtered, washed with N, N-dimethylformamide, and dried for 1-2 days to obtain the target zinc coordination polymer.

[0059] Experimental Example 1 Crystal structure determination of zinc coordination polymer in Example 1

[0060] Select the zinc coordination polymer single crystal of Example 1 of appropriate size under a microscope, use Mo-Kα treated with graphite monochromator as radiation source on X-ray single crystal diffractometer, and take ω / 2 θ Diffraction points were collected using a scattering method. All diffraction data were absorption corrected using the SADABS program. Data reduction and structure elucidation were performed using the SAINT and SHELXTL programs, respectively. The coordinates and anisotropy of non-hydrogen atoms were refined using the full-matrix least squares method. Hydrogen atoms were determined using the theoretical hydrogenation method. The crystallographic diffraction point data and structure refinement parameters are shown in Table 1 below.

[0061] Table 1 Crystallographic parameters of zinc coordination polymers of Example 1

[0062]

[0063] Experimental Example 2 Selective Fluorescence Detection of Ceftazidime by Zinc Coordination Polymers in Example 1

[0064] 1. First, 10 mg of the zinc coordination polymer material of Example 1 was dispersed in 10 mL of deionized water, ultrasonicated for 30 min, and soaked for 7 days to obtain 1 mg·mL -1 The aqueous suspension of zinc coordination polymer has the strongest fluorescence emission at 385 nm under the excitation of ultraviolet light with a wavelength of 241 nm. -1 Methanol solutions of antibiotics, including ceftazidime, cefoperazone, sulfamethoxazole, thiamphenicol, lincomycin, vancomycin, kanamycin, amoxicillin, penicillin, and erythromycin, were prepared. 1 μL of each antibiotic solution was added to 1 mg mL -1 The coordination polymer water suspension was ultrasonically mixed for 5 minutes, and then the fluorescence emission spectra of the coordination polymer when detecting different antibiotics were compared under the same excitation wavelength of 241 nm.

[0065] The results are as follows Figure 5 As shown, ceftazidime can significantly quench the fluorescence of the aqueous suspension of the zinc coordination polymer in Example 1, while the other antibiotics have little effect on its fluorescence intensity, thereby achieving selective detection of ceftazidime.

[0066] 2. Secondly, 1 μL of antibiotics other than ceftazidime was added to the aqueous suspension of the zinc coordination polymer prepared in step 1, and after ultrasonic mixing for 5 min, the fluorescence emission spectrum of the solution was measured. Then, 1 μL of ceftazidime solution was added thereto, and the fluorescence emission spectrum of the mixed solution was continued to be measured. The changes in fluorescence intensity before and after the addition of ceftazidime were compared in each group.

[0067] The results are as follows Figure 6 As shown, after adding ceftazidime, the fluorescence intensity of the coordination polymer aqueous suspension containing other antibiotics was significantly quenched, and the difference between the quenching 2 and that of ceftazidime alone was not much, thereby realizing the anti-interference detection of ceftazidime in the presence of other antibiotics.

[0068] 3. In addition, ceftazidime solution was added dropwise to the aqueous suspension of zinc coordination polymer prepared in step 1 to a concentration of 0.5-100 μmol·L -1 With the increase of ceftazidime concentration, the fluorescence intensity of the coordination polymer aqueous suspension at 385 nm gradually decreased, and Figure 7 As shown, in the range of 0.5-5.0 μmol·L -1 In the low concentration range, the fluorescence intensity of the coordination polymer aqueous suspension at 385 nm is I 0 / I There was a good linear relationship between the concentration of ceftazidime and the

[0069] 4. Finally, 1 μL of ceftazidime solution was added to the zinc coordination polymer aqueous suspension prepared in step 1. The suspension was sonicated for different times, and the corresponding fluorescence intensity was collected. The results showed that ceftazidime could effectively quench the fluorescence of the coordination polymer aqueous suspension at 60 seconds, and the quenching rate was maintained at a similar level until 20 minutes of sonication.

[0070] In summary, the zinc coordination polymer prepared by the present invention can achieve specific fluorescent recognition of ceftazidime with good selectivity and is not interfered by antibiotics such as cefoperazone, sulfamethoxazole, thiamphenicol, lincomycin, vancomycin, and amoxicillin. In the presence of multiple antibiotics, the zinc coordination polymer can still achieve fluorescent detection of ceftazidime.

Claims

1. A zinc coordination polymer, characterized in that The chemical formula of the zinc coordination polymer is {[Zn(fipa)(3-bpdb)2} n , where fipa is the completely deprotonated organic bridging ligand 5-(furan-2-yl)isophthalate, 3-bpdb is the auxiliary ligand 1, 4-bis(3-pyridyl)-2, 3-diaza-1, 3-butadiene, and n represents the degree of polymerization, a natural number. Each four-coordinated metal zinc ion at the center of a distorted tetrahedral geometry connects to two 1, 4-bis(3-pyridyl)-2, 3-diaza-1, 3-butadienes to form a V-shaped structure, which is then connected by the deprotonated 5-(furan-2-yl)isophthalate to form a long-range ordered one-dimensional chain structure along the a-axis. Adjacent chains are connected by abundant hydrogen bonds and π···π stacking interactions to form a three-dimensional supramolecular framework.

2. The zinc coordination polymer according to claim 1, characterized in that The coordination polymer belongs to the triclinic system, P -1 space group, unit cell parameters: a=10.1782 Å, b=10.4452 Å, c=15.3514 Å, α=86.4798°, β=88.5248°, γ=88.6987°, unit cell volume V=1628.0(6) Å 3 .

3. The method for preparing the zinc coordination polymer according to claim 1, characterized in that: To do this, follow these steps: 1) Add the organic ligand 5-(furan-2-yl)isophthalic acid and 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene to a mixed solvent of N,N-dimethylformamide and water, and sonicate for 10-20 minutes until completely dissolved. 2) Add 0.5 mol / L zinc nitrate solution and continue ultrasonication for 10-20 minutes to mix thoroughly. Seal the mixture and place in an oven. React at 100-120°C for 48-96 hours. Slowly cool to room temperature to obtain colorless block crystals. 3) filtering the colorless block crystals, washing with N, N-dimethylformamide, and drying for 1-2 days to obtain the target coordination polymer; Wherein, the structural formulas of 5-(furan-2-yl)isophthalic acid and 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene in step 1) are shown as formula (I) and formula (II), respectively: 。 4. The method for preparing the zinc coordination polymer according to claim 3, wherein: The molar ratio of the 5-(furan-2-yl)isophthalic acid, 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene and zinc nitrate hexahydrate is 1:1:1-2.

5. The method for preparing the zinc coordination polymer according to claim 3, wherein: In step 1), the volume ratio of N, N-dimethylformamide to water is 1:

1.

6. The method for preparing the zinc coordination polymer according to claim 3, characterized in that: In step 2), the cooling rate is 10°C / h.

7. Use of the zinc coordination polymer according to claim 1 in detecting ceftazidime, characterized in that: The zinc coordination polymer is used as a fluorescent sensor in detecting ceftazidime.

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