A fluorescent probe and its preparation method and application, and a method for detecting iron ions

Abstract

The present invention discloses a fluorescent probe and a preparation method and application thereof, and a method for detecting iron ions, and relates to the technical field of metal ion detection. The structural formula of the fluorescent probe is: The fluorescent probe provided by the present invention can detect iron ions, and the detection limit of iron ions is 60.275ppm, and because it is a fluorescent probe, it has the advantages of fast detection speed, low cost, and simple operation. In addition, the fluorescent probe has strong specificity and anti-interference ability, and can still detect iron ions in the presence of other metal ions.

Description

Technical Field

[0001] The present invention relates to the technical field of metal ion detection, and in particular to a fluorescent probe and a preparation method and application thereof, and a method for detecting iron ions. Background Art

[0002] Iron is an important metal element that is widely present in nature and is also an indispensable element in organisms. In organisms, iron ions play a key role in many physiological processes, such as oxygen transport and DNA synthesis pathways. However, excessive iron ions in the environment can cause water and soil pollution, and abnormal iron ion concentrations in organisms can cause various physiological disorders. Therefore, how to efficiently and accurately detect iron ions is particularly important in environmental science, life science, chemistry and other fields.

[0003] At present, the main methods for detecting iron ions include inductively coupled plasma atomic emission spectrometry, atomic absorption spectroscopy, inductively coupled plasma mass spectrometry, etc. Although these methods have advantages such as high sensitivity and good selectivity, these detection methods have disadvantages such as long time consumption, large-scale instruments and equipment, and complex sample pretreatment processes, which limit the wide application of these detection methods. In comparison, fluorescence detection has the advantages of simplicity, high sensitivity, and low cost. Therefore, it is of great significance to develop fluorescent probes for detecting iron ions. Summary of the invention

[0004] Based on the above-mentioned deficiencies of the prior art, the purpose of the present invention is to provide a fluorescent probe capable of detecting iron ions and a preparation method and application thereof, and a method for detecting iron ions.

[0005] The technical solution of the present invention is as follows:

[0006] In a first aspect of the present invention, a fluorescent probe is provided, wherein the structural formula of the fluorescent probe is:

[0007]

[0008] In a second aspect, the present invention provides a method for preparing the fluorescent probe as described above, comprising the following steps:

[0009] After reacting 4-(bromomethyl)benzonitrile with trifluoromethanesulfonic acid, 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine is obtained;

[0010] Adding the 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine into a first organic solvent to obtain a first mixed solution;

[0011] Will adding into a second organic solvent to obtain a second mixed solution;

[0012] The first mixed solution is added to the second mixed solution, and a reflux reaction is performed at a preset temperature for a preset time to obtain the fluorescent probe.

[0013] Optionally, the step of adding the first mixed solution to the second mixed solution and performing a reflux reaction at a preset temperature for a preset time to obtain the fluorescent probe specifically includes:

[0014] Adding the first mixed solution to the second mixed solution, and performing a reflux reaction for a preset time under a preset temperature and stirring condition to obtain a post-reaction solution;

[0015] The reaction liquid is filtered to obtain a solid product;

[0016] The solid product is washed, then placed in boiling water and stirred for 1 to 2 hours, filtered, and dried to obtain the fluorescent probe.

[0017] Optionally, the first organic solvent includes at least one of acetonitrile, methanol, N,N-dimethylacetamide, and isopropanol.

[0018] Optionally, the second organic solvent includes at least one of acetonitrile, N,N-dimethylformamide and N,N-dimethylacetamide.

[0019] Optionally, the preset temperature is 85-90° C., and the preset time is 72-85 hours.

[0020] The third aspect of the present invention provides a use of the fluorescent probe as described above in the present invention and / or the fluorescent probe prepared by the preparation method as described above in the present invention in detecting iron ions.

[0021] Optionally, the fluorescent probe is used to detect ferric ions in aqueous solution.

[0022] A fourth aspect of the present invention provides a method for detecting iron ions, comprising the following steps:

[0023] The fluorescent probe of the present invention as described above is mixed with water to prepare two dispersions with the same content of the fluorescent probe, which are respectively recorded as a first dispersion and a second dispersion;

[0024] Providing an aqueous solution to be tested and water having the same volume as the aqueous solution to be tested;

[0025] Mixing the aqueous solution to be tested with the first dispersion to obtain a first mixed solution;

[0026] Mixing water having the same volume as the aqueous solution to be tested with the second dispersion to obtain a second mixed solution;

[0027] Performing fluorescence emission spectra measurement on the first mixed solution and the second mixed solution at the same preset excitation wavelength to obtain a first fluorescence emission spectrum and a second fluorescence emission spectrum respectively;

[0028] By comparing the first fluorescence emission spectrum and the second fluorescence emission spectrum, it is detected whether the aqueous solution to be tested contains iron ions.

[0029] Optionally, if the peak value of the fluorescence intensity in the first fluorescence emission spectrum is smaller than the peak value of the fluorescence intensity in the second fluorescence emission spectrum, the aqueous solution to be tested contains iron ions, otherwise it does not contain iron ions.

[0030] Beneficial effects: The fluorescent probe provided by the present invention can detect iron ions, and the detection limit of iron ions is 60.275ppm. Since it is a fluorescent probe, it has the advantages of fast detection speed, low cost and simple operation. In addition, the fluorescent probe has strong specificity and anti-interference ability, and can still detect iron ions in the presence of other metal ions. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is the hydrogen nuclear magnetic resonance spectrum of 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine prepared in Example 1.

[0032] Figure 2 This is the carbon nuclear magnetic resonance spectrum of 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine prepared in Example 1.

[0033] Figure 3 This is a high-resolution mass spectrum of 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine prepared in Example 1.

[0034] Figure 4 This is the hydrogen nuclear magnetic resonance spectrum of the fluorescent probe prepared in Example 1.

[0035] Figure 5 This is the carbon nuclear magnetic resonance spectrum of the fluorescent probe prepared in Example 1.

[0036] Figure 6 This is the high-resolution mass spectrum of the fluorescent probe prepared in Example 1.

[0037] Figure 7 This is a graph showing the quenching effect of different metal ions on the fluorescent probe prepared in Example 1.

[0038] Figure 8 for Figure 7 The histogram corresponding to the peak value of fluorescence intensity of each fluorescence curve.

[0039] Fig. 9 This is a diagram showing the quenching of the fluorescent probe prepared in Example 1 by iron ions at different concentrations.

[0040] Fig.10 Based on Fig. 9 The fitted curve is obtained.

[0041] Fig.11 This is the anti-interference test result diagram. DETAILED DESCRIPTION

[0042] The present invention provides a fluorescent probe and a preparation method and application thereof, and a method for detecting iron ions. In order to make the purpose, technical scheme and effect of the present invention clearer and more specific, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0043] Unless otherwise defined, all technical terms and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0044] An embodiment of the present invention provides a fluorescent probe, wherein the structural formula of the fluorescent probe is:

[0045]

[0046] The fluorescent probe (bromine-containing complex) provided in the embodiment of the present invention can detect iron ions, and the detection limit of iron ions is 60.275ppm, and because it is a fluorescent probe, it has the advantages of fast detection speed, low cost and easy operation. In addition, the fluorescent probe has strong specificity and anti-interference ability, and can still detect iron ions in the presence of other metal ions.

[0047] The present invention also provides a method for preparing the fluorescent probe according to the present invention, which comprises the following steps:

[0048] S11, 4-(bromomethyl)benzonitrile After reaction with trifluoromethanesulfonic acid, 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine was obtained.

[0049] S12, adding the 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine to a first organic solvent to obtain a first mixed solution;

[0050] S13. adding into a second organic solvent to obtain a second mixed solution;

[0051] S14, adding the first mixed solution into the second mixed solution, performing a reflux reaction at a preset temperature for a preset time, to obtain the fluorescent probe.

[0052] The preparation method provided by the present invention is simple and efficient, and the fluorescent probe can be obtained by only two steps of synthesis, namely, firstly reacting 4-(bromomethyl)benzonitrile with trifluoromethanesulfonic acid to obtain 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine, and then reacting 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine with trifluoromethanesulfonic acid to obtain 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine. The fluorescent probe can be obtained by the reaction. The prepared fluorescent probe can be used for the detection of iron ions. The fluorescent probe has strong specificity and anti-interference ability, and can still detect iron ions in the presence of other metal ions.

[0053] In step S12, in some embodiments, the first organic solvent includes at least one of acetonitrile (MeCN), methanol, N,N-dimethylacetamide, and isopropanol.

[0054] In step S13, in some embodiments, the second organic solvent includes at least one of MeCN, N,N-dimethylformamide (DMF), and N,N-dimethylacetamide.

[0055] Step S14, in some embodiments, the step of adding the first mixed solution to the second mixed solution and performing a reflux reaction at a preset temperature for a preset time to obtain the fluorescent probe specifically includes:

[0056] S141, adding the first mixed solution to the second mixed solution, and performing reflux reaction for a preset time under a preset temperature and stirring condition to obtain a post-reaction solution;

[0057] S142, filtering the reaction liquid to obtain a solid product;

[0058] S142, washing the solid product, and then placing it in boiling water and stirring it for 1 to 2 hours (for example, 1 hour, 1.5 hours or 2 hours, etc.), filtering it, and drying it to obtain the fluorescent probe.

[0059] In step S141, the preset temperature is 85-90°C (for example, it can be 85°C, 86°C, 87°C, 88°C, 89°C or 90°C, etc.), and the preset time is 72-85h (for example, it can be 72h, 75h, 80h or 85h, etc.).

[0060] The embodiments of the present invention further provide a use of the fluorescent probe described above in the present invention and / or the fluorescent probe prepared by the preparation method described above in the embodiments of the present invention in detecting iron ions.

[0061] In some embodiments, the fluorescent probe is used to detect ferric ions in aqueous solution.

[0062] The present invention also provides a method for detecting iron ions, which comprises the following steps:

[0063] S21, mixing the fluorescent probe described in the embodiment of the present invention with water to prepare two dispersions with the same content of the fluorescent probe, which are respectively recorded as a first dispersion and a second dispersion;

[0064] S22, providing an aqueous solution to be tested and water with the same volume as the aqueous solution to be tested;

[0065] S23, mixing the aqueous solution to be tested with the first dispersion to obtain a first mixed solution;

[0066] S24, mixing water having the same volume as the aqueous solution to be tested with the second dispersion to obtain a second mixed solution;

[0067] S25, measuring the fluorescence emission spectra of the first mixed solution and the second mixed solution at the same preset excitation wavelength (specifically 280 nm) to obtain a first fluorescence emission spectrum and a second fluorescence emission spectrum, respectively;

[0068] S26. Detect whether the aqueous solution to be tested contains iron ions by comparing the first fluorescence emission spectrum with the second fluorescence emission spectrum.

[0069] The iron ion detection method provided by the embodiment of the present invention is simple, low in cost and high in sensitivity.

[0070] In step S26, in some embodiments, if the peak value of the fluorescence intensity in the first fluorescence emission spectrum is smaller than the peak value of the fluorescence intensity in the second fluorescence emission spectrum, the aqueous solution to be tested contains iron ions, otherwise it does not contain iron ions.

[0071] The present invention will be further described below by means of specific examples.

[0072] Example 1

[0073] This embodiment provides a method for preparing a fluorescent probe, and the synthetic route of the fluorescent probe is as follows: (1)

[0075]

[0076] The preparation method of the fluorescent probe comprises the following steps:

[0077] a. According to the above synthetic route (1), 4-(bromomethyl)benzonitrile (1.96 g, 10 mmol) was slowly added to trifluoromethanesulfonic acid (2 mL) at 0°C and N2 atmosphere, and then heated to room temperature and stirred for 12 h. Ammonia solution was then added to neutralize the solvent. The precipitate was filtered, washed with water, and dried to obtain a white powder (0.49 g, yield 99%), namely 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine.

[0078] b. According to the above synthetic route (2), 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine (1.05 g, 1.8 mmol) was added to acetonitrile (20 mL) to obtain a first mixed solution;

[0079] Will (6.03 g, 38 mmol) was mixed with DMF (50 mL) and MeCN (50 mL) to obtain a second mixed solution;

[0080] The first mixed solution was divided into five equal parts, and the parts were slowly added into the second mixed solution within 6 hours, and refluxed for 72 hours at 90° C. with stirring to obtain a post-reaction solution;

[0081] After the reaction solution was cooled to room temperature, the yellow precipitate was collected by filtration, washed with acetone (Me2CO) and dichloromethane (DCM), then placed in boiling water and stirred for 1 hour, filtered while hot, and then dried to obtain the fluorescent probe (0.91 g, yield 71%).

[0082] The H NMR spectrum of 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine is as follows Figure 1 As shown, its nuclear magnetic resonance hydrogen spectrum data is: 1 H NMR (400MHz, CDCl3-d) δ 8.69 (d, J=8.1Hz, 6H), 7.58 (d, J=8.1Hz, 6H), 4.58 (s, 6H).

[0083] The carbon NMR spectrum of 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine is as follows Figure 2 As shown, its nuclear magnetic resonance carbon spectrum data is: 13 C NMR (101MHz, CDCl3-d) δ171.26, 142.41, 136.21, 129.55, 129.49, 32.83.

[0084] The high-resolution mass spectrum of 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine is shown in Figure 3As shown, the high resolution mass spectrometry data is HRMS (ESI): Calcd for C 24 H 18 Br3N3[M+H] + 586.90, found 588.67, where Calcd for is the calculated value (the same below), and found is the measured value (the same below).

[0085] The nuclear magnetic resonance hydrogen spectrum of the fluorescent probe is as follows Figure 4 As shown, its nuclear magnetic resonance hydrogen spectrum data is 1 H NMR (400MHz, CF3COOD-d) δ9.87 (s, 2H), 9.49-9.37 (m, 4H), 9.01 (s, 8H), 8.55 (s, 2H), 8.08 (s, 8H), 6.39 (s, 6H).

[0086] The carbon NMR spectrum of the fluorescent probe is shown in Figure 5 As shown, its carbon NMR spectrum data is 13 C NMR (101MHz, CF3COOD-d) δ171.15, 149.74, 149.23, 148.26, 141.35, 133.99 , 132.02, 131.32, 120.75, 120.63, 117.92, 115.11, 112.36, 112.30, 67.05.

[0087] The fluorescent probe was tested by high-resolution mass spectrometry, and the results were as follows: Figure 6 As shown, the high-resolution mass spectrometry data obtained is HRMS (ESI): Calcd for C 42 H 31 N6O6 + [M-3Br-2H] + 715.2300, found 715.2290;

[0088] Among them, C 42 H 31 N6O6 + The structural formula is

[0089] The fluorescent probe prepared in Example 1 was tested:

[0090] (1) Cation screening test: cations that can quench the fluorescent probe were selected from 15 cations.

[0091] Add 5 mg of fluorescent probe to 5 mL to obtain a fluorescent probe concentration of 1 mg mL -1 Repeat this process to prepare 16 identical dispersions.

[0092] Add 5 mL of H2O to the first dispersion as a blank control (corresponding to Figure 7 and Figure 8 Then, 5 mL of cadmium ions (Cd 2+ ) solution, nickel ions (Ni 2+ ) solution, silver ion (Ag + ) solution, lead ion (Pb 2+ ) solution, copper ion (Cu 2+ ) solution, cobalt ions (Co 2+ ) solution, mercury ion (Hg 2+ ) solution, lithium ion (Li + ) solution, zinc ion (Zn 2+ ) solution, calcium ions (Ca 2+ ) solution, magnesium ion (Mg 2+ ) solution, aluminum ion (Al 3+ ) solution, sodium ion (Na + ) solution, potassium ion (K + ) solution and iron ions (Fe 3+ ) solution (the concentration of each ion solution is 0.01 mol / L). The fluorescence intensity was tested by a fluorescence instrument at the same voltage and the same excitation wavelength (280 nm). The results are as follows Figure 7 and 8 As shown in the figure, it can be seen that adding Fe 3+ The solution fluorescence intensity of Fe is the lowest, so it can be considered that Fe 3+ It has the effect of quenching the fluorescence of the fluorescent probe, that is, the fluorescent probe can be used to detect Fe 3+ .

[0093] (2)Fe 3+ Titration quenching test

[0094] Add 5 mg of fluorescent probe to 5 mL to obtain a fluorescent probe concentration of 1 mg mL -1 Repeat this process to prepare 21 identical dispersions.

[0095] The first dispersion was not added with any substance and used as blank (corresponding to Fig. 9 0ppm in

[0096] 0.01 mol / L ferric nitrate nonahydrate solution was added to the remaining 20 portions of dispersion liquid in the amounts of 1d, 2d, 3d, 4d, 5d, 6d, 7d, 8d, 9d, 10d, 15d, 19d, 25d, 32d, 39d, 49d, 67d, 100d, 150d, and 200d (where 1d = 50 μL), and the fluorescence intensity of the mixed solution after adding the ferric nitrate nonahydrate solution was tested by a fluorescence machine under the same voltage and the same excitation wavelength (280 nm). Fig. 9 It can be seen that the fluorescence of the fluorescent probe can be quenched to below 100 when the ferric nitrate nonahydrate solution is added for 200 days.

[0097] Fig. 9 In the figure, 0 ppm represents a blank control without adding ferric nitrate nonahydrate solution, and 40 ppm (1 ppm = 1 mg / L) represents the concentration of ferric nitrate nonahydrate in the mixed solution after adding ferric nitrate nonahydrate solution for 1 day to the dispersion.

[0098] The titration fitting curve obtained by this test is as follows Fig.10 As shown, I0 represents the initial fluorescence intensity (i.e., the fluorescence intensity without adding the ferric nitrate nonahydrate solution), and I represents the fluorescence intensity after adding the ferric nitrate nonahydrate solution.

[0099] This test yields Fe 3+ The detection lines are shown in Table 1.

[0100] Table 1. Fe 3+ Testing line

[0101] Titration (σ=0.034156) Kv <![CDATA[R 2 ]]> LOD / ppm <![CDATA[0.01mol / L Fe 3+ ]]> 0.0017 0.99415 60.275

[0102] σ represents the standard deviation of the initial intensity of the fluorescent probe, σ is 0.034156;

[0103] K SV represents the fluorescence quenching constant in the Stern-Volmer equation, Ksv is 0.0017;

[0104] LOD represents the limit of detection, LOD==3σ / Ksv=(3×0.034156) / 0.0017=60.275ppm.

[0105] (3) Anti-interference test

[0106] Add 5 mg of fluorescent probe to 5 mL to obtain a fluorescent probe concentration of 1 mg mL -1 Dispersion, repeat this process to prepare 13 identical dispersions;

[0107] Add 5 mL of H2O to the first dispersion as a blank control (corresponding to Fig.111) in the above table;

[0108] Add 3 mL of Fe 3+ solution and 2 mL of Mg 2+ Solution;

[0109] Add 3 mL of Fe 3+ solution and 2mL of Pb 2+ Solution;

[0110] Add 3 mL of Fe 3+ solution and 2mL of Hg 2+ Solution;

[0111] Add 3 mL of Fe 3+ solution and 2mL of Zn 2+ Solution;

[0112] Add 3 mL of Fe 3+ solution and 2 mL of Li + Solution;

[0113] Add 3 mL of Fe 3+ solution and 2 mL of Ca 2+ Solution;

[0114] Add 3 mL of Fe 3+ solution and 2 mL of Cu 2+ Solution;

[0115] Add 3 mL of Fe 3+ solution and 2mL of Ni 2+ Solution;

[0116] Add 3 mL of Fe 3+ Solution, 1mL of K + solution and 1 mL of Na + Solution;

[0117] Add 3 mL of Fe 3+ Solution, 1mL of Ag + solution and 1 mL of Cd 2+ Solution;

[0118] Add 3 mL of Fe 3+ solution, 1 mL of Co 2+ solution and 1 mL of Cu 2+ Solution;

[0119] Add 3 mL of Fe3+ Solution, 1mL of Al 3+ solution and 1 mL of Cu 2+ Solution; The different ion solutions used above (such as Mg 2+ Solution, Al 3+ The concentration of the solutions (not listed here) is 0.01 mol / L.

[0120] The fluorescence intensity of each mixed solution was tested by a fluorescence instrument under the same voltage and the same excitation wavelength (280nm). Fig.11 It can be seen that (Fe 3+ / Mg 3+ Indicates adding 3 mL of Fe to the dispersion 3+ solution and 2 mL of Mg 2+ solution, and the meanings of other similar expressions are analogous), adding other ion solutions does not affect Fe 3+ The quenching of the fluorescent probe indicates that the fluorescent probe acts as a Fe 3+ The fluorescent probe is specific.

[0121] In summary, the present invention provides a fluorescent probe and its preparation method and application, and a method for detecting iron ions. The fluorescent probe can detect iron ions, and the detection limit of iron ions is 60.275ppm. Since it is a fluorescent probe, it has the advantages of fast detection speed, low cost, and simple operation. In addition, the fluorescent probe has strong specificity and anti-interference ability, and can still detect iron ions in the presence of other metal ions.

[0122] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A fluorescent probe, characterized in that The structural formula of the fluorescent probe is:

2. A method for preparing the fluorescent probe according to claim 1, characterized in that: The steps include: After reacting 4-(bromomethyl)benzonitrile with trifluoromethanesulfonic acid, 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine is obtained; Adding the 2,4,6-tris(4-(bromomethyl)phenyl)-1,3,5-triazine into a first organic solvent to obtain a first mixed solution; Will adding into a second organic solvent to obtain a second mixed solution; The first mixed solution is added to the second mixed solution, and a reflux reaction is performed at a preset temperature for a preset time to obtain the fluorescent probe.

3. The preparation method according to claim 2, characterized in that: The step of adding the first mixed solution to the second mixed solution and performing a reflux reaction at a preset temperature for a preset time to obtain the fluorescent probe specifically includes: Adding the first mixed solution to the second mixed solution, and performing a reflux reaction for a preset time under a preset temperature and stirring condition to obtain a post-reaction solution; The reaction liquid is filtered to obtain a solid product; The solid product is washed, then placed in boiling water and stirred for 1 to 2 hours, filtered, and dried to obtain the fluorescent probe.

4. The preparation method according to claim 2 or 3, characterized in that: The first organic solvent includes at least one of acetonitrile, methanol, N,N-dimethylacetamide, and isopropanol.

5. The preparation method according to claim 2 or 3, characterized in that: The second organic solvent includes at least one of acetonitrile, N,N-dimethylformamide, and N,N-dimethylacetamide.

6. The preparation method according to claim 2 or 3, characterized in that: The preset temperature is 85-90° C., and the preset time is 72-85 hours.

7. Use of the fluorescent probe according to claim 1 and / or the fluorescent probe prepared by the preparation method according to any one of claims 2 to 6 in detecting iron ions for purposes other than disease diagnosis.

8. The use according to claim 7, characterized in that: The fluorescent probe is used to detect trivalent iron ions in aqueous solution.

9. A method for detecting iron ions for non-disease diagnosis purposes, characterized in that: The steps include: The fluorescent probe according to claim 1 is mixed with water to prepare two dispersions with the same content of the fluorescent probe, which are respectively referred to as a first dispersion and a second dispersion; Providing an aqueous solution to be tested and water having the same volume as the aqueous solution to be tested; Mixing the aqueous solution to be tested with the first dispersion to obtain a first mixed solution; Mixing water having the same volume as the aqueous solution to be tested with the second dispersion to obtain a second mixed solution; Performing fluorescence emission spectra measurement on the first mixed solution and the second mixed solution at the same preset excitation wavelength to obtain a first fluorescence emission spectrum and a second fluorescence emission spectrum respectively; By comparing the first fluorescence emission spectrum and the second fluorescence emission spectrum, it is detected whether the aqueous solution to be tested contains iron ions.

10. The detection method according to claim 9, characterized in that: If the peak value of the fluorescence intensity in the first fluorescence emission spectrum is smaller than the peak value of the fluorescence intensity in the second fluorescence emission spectrum, the aqueous solution to be tested contains iron ions, otherwise it does not contain iron ions.

Images