Method for detecting Al < 3 + > in water environment with high sensitivity
By preparing Schiff base organic fluorescent materials and utilizing the blue shift of the fluorescence emission peak to achieve high-sensitivity detection of Al3+, the problems of long response time, high equipment cost and interference with other metal ions in the existing technology for detecting Al3+ are solved, providing a simple and rapid detection method.
Patent Information
- Application Number
- CN202510916051.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-03
- Publication Date
- 2025-09-19
AI Technical Summary
Existing technologies have problems such as long response time, high equipment cost, sensitivity to interference from other metal ions, and complex sample pretreatment when detecting Al3+ in water environments, making it difficult to achieve high sensitivity and rapid detection.
Schiff base organic fluorescent materials were synthesized at room temperature using o-phenylenediamine and 2,6-dialdehyde-1,5-dihydroxynaphthalene as raw materials and ethanol as solvent. The qualitative and quantitative detection of Al3+ was achieved by the blue shift of the fluorescence emission peak, and a standard curve between fluorescence intensity and Al3+ concentration was constructed.
The method realizes efficient preparation and high-sensitivity detection of fluorescent materials, is simple and fast to operate, has a wide detection range, good specificity, and a low detection limit, and is suitable for on-site detection.
Smart Images
Figure CN120668624A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of fluorescent material molecular synthesis and chemical sensors, and in particular to a method for highly sensitive detection of Al in water environment. 3+ method. Background Art
[0002] Al 3+ The detection of chlorinated parasites is of great significance in environmental monitoring, food safety, and biomedicine. Commonly used detection methods include ion-selective electrodes, spectroscopy (such as atomic absorption spectroscopy and fluorescence spectroscopy), chromatography, and electrochemical methods. Although these methods have made some progress in sensitivity and selectivity, they still have some shortcomings.
[0003] First, while traditional ion-selective electrode methods offer high selectivity, they suffer from long response times and are sensitive to interference from other metal ions, compromising the accuracy of measurement results. Second, while spectroscopic methods can achieve highly sensitive detection, they often require complex sample pretreatment and are associated with high equipment costs, making them unsuitable for rapid on-site testing. Furthermore, electrochemical methods can be constrained by the stability of electrode materials and reaction conditions in practical applications, impacting repeatability and reliability. Therefore, developing novel, efficient aluminum ion detection technologies to overcome the shortcomings of existing methods remains an important direction for future research. Summary of the Invention
[0004] The technical problem to be solved by the present invention is to provide a method for detecting Al in water environment with high sensitivity in view of the above-mentioned deficiencies in the prior art. 3+ The present invention proposes a method for efficiently preparing schiff base organic fluorescent materials, which can solve the problems of few existing preparation methods, complex procedures and high costs. The method can achieve efficient and large-scale preparation of red fluorescent materials and be applied to Al in water. 3+ Qualitative and quantitative detection can enrich Al 3+ Detection and realization of Al 3+ High sensitivity and rapid detection. This method uses o-phenylenediamine and 2,6-dialdehyde-1,5-dihydroxynaphthalene as raw materials, ethanol as solvent, and synthesizes organic fluorescent materials at room temperature. The probe has the characteristics of wide excitation wavelength. When excited in the range of 320-600nm, it can achieve fluorescence emission at 624nm; when Al is added 3+ After that, the fluorescent material forms a more ordered and compact aggregate. This structural change leads to a change in the π-π stacking mode between molecules, reducing the degree of conjugation in the excited state, thereby causing the fluorescence to blue-shift to 518nm. According to the change of fluorescence and its intensity at 518nm, the Al in water environment can be realized. 3+ Qualitative and quantitative detection.
[0005] To achieve the above object, the technical solution adopted by the present invention is: a highly sensitive detection method for Al 3+ The method comprises the following steps:
[0006] S1. Provide a fluorescent material, which has a fluorescence emission peak at 624 nm under excitation light. 3+ After binding, the fluorescence emission peak of the fluorescent material blue-shifted to 518 nm;
[0007] S2. Mixing the fluorescent material and the sample to be tested in a solution, and measuring the fluorescence intensity of the resulting product at 518 nm under excitation light;
[0008] S3, according to the fluorescence intensity at 518nm, using the pre-built characterization of the fluorescence intensity at 518nm and Al 3+ The concentration relationship of the standard curve was analyzed to obtain the Al content in the sample to be tested. 3+ concentration.
[0009] Preferably, the excitation light wavelength is 320-600 nm.
[0010] Preferably, the fluorescent material is prepared by the following method:
[0011] o-phenylenediamine and 2,6-dialdehyde-1,5-dihydroxynaphthalene are mixed in a solvent in a molar ratio, ultrasonically dispersed and then stirred for reaction, the obtained solution is centrifuged, and the solid at the bottom is collected, washed, and vacuum dried to obtain a fluorescent material.
[0012] Preferably, the solvent is anhydrous ethanol; the stirring reaction temperature is room temperature, and the reaction time is 12-48 hours.
[0013] Preferably, the fluorescent material is prepared by the following method:
[0014] O-phenylenediamine and 2,6-dialdehyde-1,5-dihydroxynaphthalene are mixed in a molar ratio of 10 to 0.5:1, added to anhydrous ethanol, ultrasonically dispersed for 15 to 60 minutes, and then stirred for reaction at room temperature for 12 to 48 hours. The resulting solution is centrifuged, and the bottom solid is collected, washed with ethanol 2 to 6 times, and then vacuum dried at 50 to 70°C for 12 to 48 hours to obtain a fluorescent material.
[0015] Preferably, the fluorescent material is prepared by the following method:
[0016] O-phenylenediamine and 2,6-dialdehyde-1,5-dihydroxynaphthalene were mixed in a molar ratio of 2:1, added to anhydrous ethanol, ultrasonically dispersed for 30 minutes, and then stirred at room temperature for 24 hours. The resulting solution was centrifuged, and the bottom solid was collected, washed with ethanol three times, and then vacuum dried at 60°C for 24 hours to obtain a fluorescent material.
[0017] Preferably, the sample to be tested is Al-containing 3+ of aqueous solution.
[0018] Preferably, the highly sensitive detection of Al in water environment 3+ The method comprises the following steps:
[0019] S1. Provide a fluorescent material, which has a fluorescence emission peak at 624 nm under excitation light. 3+ After binding, the fluorescence emission peak of the fluorescent material blue-shifted to 518 nm;
[0020] S2. Disperse the fluorescent material in ethanol to obtain a concentration of 0.01-1 mg mL -1 A fluorescent material solution is prepared, and the fluorescence intensity of the fluorescent material solution at 518 nm under excitation light is measured, which is recorded as F0. The fluorescent material solution is then mixed with the sample to be tested for 1-60 minutes, and the fluorescence intensity of the resulting product at 518 nm under excitation light is measured, which is recorded as F0.
[0021] S3, according to the value of F / F0, use the pre-built characterization of the fluorescence intensity at 518nm and Al 3+ The concentration relationship of the standard curve was analyzed to obtain the Al content in the sample to be tested. 3+ concentration.
[0022] Preferably, the standard curve is constructed by the following method:
[0023] 1) Prepare a series of Al 3+ Aqueous solution, as Al 3+ Working fluid;
[0024] 2) Dispersing the fluorescent material in ethanol to prepare a fluorescent material solution, and measuring the fluorescence intensity of the fluorescent material solution at 518 nm under excitation light, which is recorded as F0;
[0025] 3) To each Al 3+ The same volume of fluorescent material solution was added to the working solution, and the fluorescence intensity of the obtained products at 518 nm under the excitation light was measured after mixing, which was recorded as F; the value of F / F0 was used as the vertical axis, and Al 3+ The concentration is used as the horizontal axis for curve fitting to obtain the standard curve.
[0026] Preferably, the standard curve is constructed by the following method:
[0027] 1) Prepare a series of Al 3+ Aqueous solution, as Al 3+ Working fluid, Al3+ Al in the working fluid 3+ The concentration range is 0–800 μM;
[0028] 2) Disperse the fluorescent material in ethanol to obtain a concentration of 0.01-1 mg mL -1 The fluorescent material solution is tested, and the fluorescence intensity of the fluorescent material solution at 518nm under the excitation light is recorded as F0;
[0029] 3) To each Al 3+ The same volume of fluorescent material solution was added to the working solution, and the fluorescence intensity of the obtained product at 518 nm under 480 nm excitation light was measured after mixing for 1-60 min, which was recorded as F. The value of F / F0 was used as the vertical axis, and Al 3+ The concentration is used as the horizontal axis for curve fitting to obtain the standard curve.
[0030] The beneficial effects of the present invention are:
[0031] (1) The preparation method of the fluorescent material provided by the present invention is simple, has low equipment requirements, high yield, and low cost; in addition, the fluorescent material has stable luminescence and a wide excitation wavelength, making it particularly suitable as a probe molecule for fluorescence sensing applications;
[0032] (2) The fluorescent material and Al 3+ After combination, the fluorescence emission can be blue-shifted and the fluorescence at 518nm is enhanced, and its effect on Al 3+ It has specific recognition performance and a wide detection range: 20-400μM.
[0033] (3) The present invention is based on the detection of Al in water environment constructed by the fluorescent material 3+ The method has the advantages of simple operation, rapidity, high efficiency, good specificity and low detection limit. BRIEF DESCRIPTION OF THE DRAWINGS
[0034] Figure 1 This is the emission spectrum of fluorescent materials at different excitation wavelengths;
[0035] Figure 2 is the fluorescence intensity of fluorescent materials with different concentrations under 480nm excitation;
[0036] Figure 3 The fluorescence intensity changes at 518 nm after the reaction of different metal ions with fluorescent materials;
[0037] Figure 4 For fluorescent materials and Al 3+ Fluorescence spectra after different reaction times;
[0038] Figure 5 For different concentrations of Al3+ Effect on the fluorescence intensity of fluorescent materials;
[0039] Figure 6 is the standard curve obtained by fitting. DETAILED DESCRIPTION
[0040] The present invention is further described in detail below with reference to the embodiments so that those skilled in the art can implement the invention with reference to the description.
[0041] It should be understood that terms such as “having”, “including” and “comprising” used herein do not preclude the existence or addition of one or more other elements or combinations thereof.
[0042] Unless otherwise specified, the experimental methods used in the following examples are conventional methods. Materials and reagents used in the following examples are commercially available unless otherwise specified. In the following examples, where specific conditions are not specified, the experiments were conducted under conventional conditions or those recommended by the manufacturer. Reagents and instruments used, where the manufacturer is not specified, are commercially available conventional products.
[0043] Example 1
[0044] A fluorescent material is prepared by the following method:
[0045] (1) o-phenylenediamine and 2,6-dialdehyde-1,5-dihydroxynaphthalene were placed in a beaker at a molar ratio of 2:1, and anhydrous ethanol was added. The ratio of the total mass (g) of o-phenylenediamine and 2,6-dialdehyde-1,5-dihydroxynaphthalene to the volume (mL) of anhydrous ethanol was 1:40. After ultrasonic dispersion for 30 minutes, the mixture was magnetically stirred at room temperature for 24 hours to obtain a product solution.
[0046] (2) The product solution was centrifuged, the solid at the bottom was collected, and washed with ethanol three times;
[0047] (3) The solid obtained in step (2) was placed in a vacuum drying oven and dried at 60° C. for 24 h to obtain a fluorescent material.
[0048] The fluorescent material has the following characteristics: it has a fluorescence emission peak at 624nm under excitation light, and when the fluorescent material is combined with Al 3+ After the combination, the fluorescence emission peak of the fluorescent material blue-shifts to 518nm; based on this characteristic, it can be used for Al 3+ Detection.
[0049] Example 2
[0050] A fluorescent material is prepared by the following method:
[0051] (1) o-phenylenediamine and 2,6-dialdehyde-1,5-dihydroxynaphthalene were placed in a beaker at a molar ratio of 2:1, and anhydrous ethanol was added. The ratio of the total mass (g) of o-phenylenediamine and 2,6-dialdehyde-1,5-dihydroxynaphthalene to the volume (mL) of anhydrous ethanol was 1:30. After ultrasonic dispersion for 45 minutes, the mixture was magnetically stirred at room temperature for 12 hours to obtain a product solution.
[0052] (2) The product solution was centrifuged, the solid at the bottom was collected, and washed with ethanol three times;
[0053] (3) The solid obtained in step (2) was placed in a vacuum drying oven and dried at 60° C. for 24 h to obtain a fluorescent material.
[0054] The fluorescent material has the following characteristics: it has a fluorescence emission peak at 624nm under excitation light, and when the fluorescent material is combined with Al 3+ After the combination, the fluorescence emission peak of the fluorescent material blue-shifts to 518nm; based on this characteristic, it can be used for Al 3+ Detection.
[0055] Example 3
[0056] A fluorescent material is prepared by the following method:
[0057] (1) o-phenylenediamine and 2,6-dialdehyde-1,5-dihydroxynaphthalene were placed in a beaker at a molar ratio of 2:1, and anhydrous ethanol was added. The ratio of the total mass (g) of o-phenylenediamine and 2,6-dialdehyde-1,5-dihydroxynaphthalene to the volume (mL) of anhydrous ethanol was 1:50. After ultrasonic dispersion for 30 minutes, the mixture was magnetically stirred at room temperature for 24 hours to obtain a product solution.
[0058] (2) The product solution was centrifuged, the solid at the bottom was collected, and washed with ethanol three times;
[0059] (3) The solid obtained in step (2) was placed in a vacuum drying oven and dried at 60° C. for 24 h to obtain a fluorescent material.
[0060] The fluorescent material has the following characteristics: it has a fluorescence emission peak at 624nm under excitation light, and when the fluorescent material is combined with Al 3+ After the combination, the fluorescence emission peak of the fluorescent material blue-shifts to 518nm; based on this characteristic, it can be used for Al 3+ Detection.
[0061] Example 4
[0062] A highly sensitive method for detecting Al in water environment 3+ The method comprises the following steps:
[0063] S1. Provide the fluorescent material of any one of Examples 1-3;
[0064] S2. Disperse the fluorescent material in ethanol to obtain a concentration of 0.1 mg mL -1 A fluorescent material solution was prepared, and the fluorescence intensity of the fluorescent material solution at 518 nm under 480 nm excitation light was tested, which was recorded as F0. The fluorescent material solution was then mixed with aluminum ion standard solutions of different concentrations for 40 min, and the fluorescence intensity of the resulting product at 518 nm under 480 nm excitation light was tested, which was recorded as F. A standard curve was constructed based on different aluminum ion concentrations and the corresponding F / F0 values;
[0065] S3, monitor the fluorescence intensity of the solution after the water sample to be tested and the probe are mixed in a volume ratio of 1:1 under the excitation light of 480nm at 518nm, record it as F', calculate the value of F' / F0, and use the pre-built characterization of the fluorescence intensity at 518nm and Al 3+ The concentration relationship of the standard curve was analyzed to obtain the Al content in the sample to be tested. 3+ concentration.
[0066] The standard curve is constructed by the following method:
[0067] 1) Prepare a series of Al 3+ Aqueous solution, as Al 3+ Working fluid, Al 3+ Al in the working fluid 3+ The concentration range is 0–800 μM;
[0068] 2) Disperse the fluorescent material in ethanol to obtain a concentration of 0.1 mg mL -1 The fluorescent material solution is tested, and the fluorescence intensity of the fluorescent material solution at 518nm under the excitation light is recorded as F0;
[0069] 3) To each Al 3+ The same volume of fluorescent material solution was added to the working solution, and after mixing for 40 minutes, the fluorescence intensity of the obtained products at 518 nm under 480 nm excitation light was measured, which was recorded as F; the value of F / F0 was used as the vertical axis, and Al 3+ The concentration was used as the horizontal axis for curve fitting to obtain the standard curve.
[0070] Performance characterization and testing:
[0071] 1. Reference Figure 1 Figure 2 shows the emission spectra of the fluorescent material prepared in Example 1 at different excitation wavelengths. The spectra show that the optimal excitation wavelength for the fluorescent material is 480 nm, with the optimal emission peak at 624 nm. While the emission peak position of the probe remains constant with changes in excitation wavelength, the fluorescence intensity varies, demonstrating that the fluorescent material prepared in this invention exhibits excitation wavelength independence.
[0072] 2. Reference Figure 2 , which is a graph showing the fluorescence change of ethanol solutions of the fluorescent material prepared in Example 1 at different concentrations under 480 nm excitation. The results show that the concentration is 0.1 mg mL -1 The fluorescence is strongest.
[0073] 3. Reference Figure 3 , is the change of fluorescence intensity at 518nm after different metal ions react with fluorescent materials. After different metal ions are mixed with the ethanol solution of the fluorescent material prepared in Example 1, the change of the ratio of the fluorescence intensity (F) at 518nm wavelength to the original intensity (F0, i.e., the fluorescence intensity of the ethanol solution of the fluorescent material when not mixed with metal ions) is monitored. As can be seen from the figure, Al 3+ The most obvious change was caused by the introduction of 3+ It has strong specific recognition ability.
[0074] 4. Reference Figure 4 , is Al 3+ The fluorescence change diagram after adding the fluorescent material prepared in Example 1 into the ethanol solution for different reaction times shows that the optimal reaction time is 40 minutes.
[0075] 5. Figure 5 For different concentrations of Al 3+ The change of fluorescence intensity at 518 nm after the reaction of (1-500 μM) with the ethanol solution of the fluorescent material prepared in Example 1 shows that as Al 3+ With the increase of concentration, the fluorescence intensity at 518 nm gradually increased. Figure 6 The standard curve obtained by fitting in Example 4 has a good linear relationship when the final concentration is 20-400 μM. The fitting straight line equation is y=-3.71104+0.34789x, and the fitting coefficient R 2 =0.9852. Where x is Al 3+ The concentration of α-aminobutyric acid is α-aminobutyric acid, y is F / F0. The detection limit is 1.2 μM.
[0076] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the description and implementation methods. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to specific details.
Claims
1. A highly sensitive method for detecting Al in water environment 3+ The method is characterized in that The following steps are involved: S1. Provide a fluorescent material, which has a fluorescence emission peak at 624 nm under excitation light. 3+ After binding, the fluorescence emission peak of the fluorescent material blue-shifted to 518 nm; S2. Mixing the fluorescent material and the sample to be tested in a solution, and measuring the fluorescence intensity of the resulting product at 518 nm under excitation light; S3, according to the fluorescence intensity at 518nm, using the pre-built characterization of the fluorescence intensity at 518nm and Al 3+ The concentration relationship of the standard curve was analyzed to obtain the Al content in the sample to be tested. 3+ concentration.
2. The highly sensitive detection of Al in water environment according to claim 1 3+ The method is characterized in that The excitation light wavelength is 320-600nm.
3. The highly sensitive detection of Al in water environment according to claim 1 3+ The method is characterized in that The fluorescent material is prepared by the following method: o-phenylenediamine and 2,6-dialdehyde-1,5-dihydroxynaphthalene are mixed in a solvent in a molar ratio, ultrasonically dispersed and then stirred for reaction, the obtained solution is centrifuged, and the solid at the bottom is collected, washed, and vacuum dried to obtain a fluorescent material.
4. The highly sensitive detection of Al in water environment according to claim 3 3+ The method is characterized in that The solvent is anhydrous ethanol; the stirring reaction temperature is room temperature, and the reaction time is 12-48 hours.
5. according to claim 4 highly sensitive detection Al in water environment 3+ The method is characterized in that The fluorescent material is prepared by the following method: O-phenylenediamine and 2,6-dialdehyde-1,5-dihydroxynaphthalene are mixed in a molar ratio of 10 to 0.5:1, added to anhydrous ethanol, ultrasonically dispersed for 15 to 60 minutes, and then stirred for reaction at room temperature for 12 to 48 hours. The resulting solution is centrifuged, and the bottom solid is collected, washed with ethanol 2 to 6 times, and then vacuum dried at 50 to 70°C for 12 to 48 hours to obtain a fluorescent material.
6. The highly sensitive detection of Al in water environment according to claim 5 3+ The method is characterized in that The fluorescent material is prepared by the following method: O-phenylenediamine and 2,6-dialdehyde-1,5-dihydroxynaphthalene were mixed in a molar ratio of 2:1, added to anhydrous ethanol, ultrasonically dispersed for 30 minutes, and then stirred at room temperature for 24 hours. The resulting solution was centrifuged, and the bottom solid was collected, washed with ethanol three times, and then vacuum dried at 60°C for 24 hours to obtain a fluorescent material.
7. The highly sensitive detection of Al in water environment according to claim 1 3+ The method is characterized in that The sample to be tested contains Al 3+ of aqueous solution.
8. The highly sensitive detection of Al in water environment according to claim 7 3+ The method is characterized in that The following steps are involved: S1. Provide a fluorescent material, which has a fluorescence emission peak at 624 nm under excitation light. 3+ After binding, the fluorescence emission peak of the fluorescent material blue-shifted to 518 nm; S2. Disperse the fluorescent material in ethanol to obtain a concentration of 0.01-1 mg mL -1 A fluorescent material solution is prepared, and the fluorescence intensity of the fluorescent material solution at 518 nm under excitation light is measured, which is recorded as F0. The fluorescent material solution is then mixed with the sample to be tested for 1-60 minutes, and the fluorescence intensity of the resulting product at 518 nm under excitation light is measured, which is recorded as F0. S3, according to the value of F / F0, use the pre-built characterization of the fluorescence intensity at 518nm and Al 3+ The concentration relationship of the standard curve was analyzed to obtain the Al content in the sample to be tested. 3+ concentration.
9. The highly sensitive detection of Al in water environment according to claim 1 3+ The method is characterized in that The standard curve was constructed by the following method: 1) Prepare a series of Al 3+ Aqueous solution, as Al 3+ Working fluid; 2) Dispersing the fluorescent material in ethanol to prepare a fluorescent material solution, and measuring the fluorescence intensity of the fluorescent material solution at 518 nm under excitation light, which is recorded as F0; 3) To each Al 3+ The same volume of fluorescent material solution was added to the working solution, and the fluorescence intensity of the obtained products at 518 nm under the excitation light was measured after mixing, which was recorded as F; the value of F / F0 was used as the vertical axis, and Al 3+ The concentration is used as the horizontal axis for curve fitting to obtain the standard curve.
10. The highly sensitive detection method for Al in water environment according to claim 9. 3+ The method is characterized in that The standard curve was constructed by the following method: 1) Prepare a series of Al 3+ Aqueous solution, as Al 3+ Working fluid, Al 3+ Al in the working fluid 3+ The concentration range is 0–800 μM; 2) Disperse the fluorescent material in ethanol to obtain a concentration of 0.01-1 mg mL -1 The fluorescent material solution is tested, and the fluorescence intensity of the fluorescent material solution at 518nm under the excitation light is recorded as F0; 3) To each Al 3+ The same volume of fluorescent material solution was added to the working solution, and the fluorescence intensity of the obtained product at 518 nm under 480 nm excitation light was measured after mixing for 1-60 min, which was recorded as F. The value of F / F0 was used as the vertical axis, and Al 3+ The concentration is used as the horizontal axis for curve fitting to obtain the standard curve.