Novel fluorescence probe for detecting Fe < 3 + > as well as preparation method and application of novel fluorescence probe

Abstract

The invention discloses a novel Fe < 3 + > detection fluorescent probe and a preparation method and application thereof, and belongs to the technical field of chemical analysis and detection.The preparation method comprises the following steps that rhodamine 6G and ethidene diamine react to obtain a product 1; and reacting the product 1 with 2, 3, 4-trihydroxy benzaldehyde to obtain the novel fluorescent probe L for detecting Fe < 3 + >. The novel Fe < 3 + > detection fluorescent probe molecule L synthesized by the invention can specifically select iron ions with high sensitivity and is not interfered by other cations in the process. The synthesized novel fluorescence probe molecule L for detecting Fe < 3 + > can identify iron ions in an acetonitrile solution, and has a good application prospect in the aspect of cation detection.

Description

Technical Field

[0001] The present invention relates to a novel fluorescent probe for detecting Fe 3+ and its preparation method and application, belonging to the technical field of chemical analysis and detection. Background Art

[0002] Fe 3+ plays an important role in key biological and biophysical processes, exists in the form of ions in cells, and has the highest content in organisms. Fe 3+ is involved in many basic physiological processes in organisms and plays an important role in them, including key biological and biophysical processes such as enzymatic reactions, oxygen binding in hemoglobin, RNA and DNA synthesis, electron-proton transfer, transcriptional regulation, and nerve conduction. Iron is essential in organisms, but excessive intake should also be avoided, and it is crucial to maintain it within a narrow content range. Both iron deficiency and iron overload can cause various physiological disorders and have an adverse impact on health. Insufficient intake of Fe 3+ can lead to iron deficiency anemia, resulting in symptoms such as impaired cognitive function and weakened immune system, and can also cause mental problems, especially in children. Excessive deposition of Fe 3+ in the body will cause oxidative stress, damage cell structure, and damage tissues and organs, especially having potential harm to important organs such as the liver and heart of organisms. In addition, excessive intake of Fe 3+ will also exceed the clearance capacity range of the metal ion elimination system in the body, resulting in iron deposition in organs and causing symptoms of iron poisoning in organisms, such as diarrhea and vomiting in mild cases, and abnormal liver and kidney functions in severe cases. The pollution of water by metal pollutants, especially metal pollutants such as copper, cadmium, zinc, lead, mercury, arsenic, silver, chromium, iron, and platinum, has become an urgent environmental problem and has received a lot of research attention in recent years. Given its importance in biology and human health, it is particularly important to selectively and sensitively detect the concentration of Fe 3+ in real time.

[0003] To achieve the goal of detecting Fe 3+ several advanced instrumental techniques have been developed by researchers. Several classical analytical techniques, including atomic absorption spectroscopy, inductively coupled plasma mass spectrometry, colorimetry, spectrophotometry, and voltammetry, have been used for Fe 3+Qualitative and quantitative detection. These detection methods have obvious drawbacks. The establishment of complex instrument technologies and fully equipped laboratories requires a large amount of capital and infrastructure investment. Problems such as the requirements for complex equipment, time-consuming sample preparation procedures, and the need for on-site deployable analysis technologies also limit the detectable range. Fluorescent probes have the advantages of convenience, speed, high sensitivity, and good selectivity, thus enabling the effective and timely assessment of metal pollution in water, soil, and food samples to mitigate risks. Summary of the Invention

[0004] To solve the defects such as high detection cost in the prior art, the present invention provides a novel fluorescent probe for detecting Fe 3+ and its preparation method and application, which can highly sensitively and specifically select iron ions and is not interfered by other cations during the process. 3+ To solve the above technical problems, the technical solutions adopted by the present invention are as follows:

[0005] A novel fluorescent probe for detecting Fe The molecular formula of which is: 3+

[0006] The present invention also provides a preparation method of a novel fluorescent probe for detecting Fe 3+ which includes the following steps: (1) React rhodamine 6G with ethylenediamine to obtain product 1; (2) React product 1 with 2,3,4-trihydroxybenzaldehyde to obtain the novel fluorescent probe L for detecting Fe 3+ ; The reaction process formula is: .

[0007] Preferably, the reaction temperature in step (1) is 70~80 °C, the reaction time is 3~8 h, and the reaction solvent is ethanol.

[0008] Preferably, the reaction temperature in step (2) is 70~80 °C, the reaction time is 2~6 h, and the reaction solvent is ethanol.

[0009] Meanwhile, the present invention provides an application of a novel fluorescent probe for detecting Fe 3+ The application process includes: Prepare a solution of the novel fluorescent probe for detecting Fe 3+ and add Fe 2+ , Fe 3+ , Mg 2+ , Na + , Hg 2+ , Ce 3+ , Co2+ , Cd 2 + , Ni 2+ , Ba 2+ , Pb 2+ , Cu 2+ , K + , Ag + , Zn 2+ , Y 3+ , Al 3+ , Sr 2+ , Ca 2+ , Mn 2+ solution, and measure the fluorescence intensity.

[0010] Preferably, the solvent of the novel Fe 3+ fluorescence probe solution is acetonitrile, and the novel Fe 3+ concentration of the fluorescence probe solution is 1×10 -4 moL / L.

[0011] Technologies not mentioned in the present invention shall refer to the prior art.

[0012] The novel Fe 3+ fluorescence probe molecule L synthesized in the present invention can specifically and highly sensitively select ferric ions and is not interfered by other cations during the process. The novel Fe 3+ fluorescence probe molecule L synthesized in the present invention can recognize ferric ions in an acetonitrile solution and has good application prospects in cation detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is the cation response diagram of the novel Fe 3+ fluorescence probe L prepared in Example 1 under a 365 nm ultraviolet lamp; Figure 2 is the fluorescence emission spectra of the novel Fe 3+ fluorescence probe molecule L prepared in Example 1 and different cations; Figure 3 is the response time scatter plot of the novel Fe 3+ fluorescence probe L prepared in Example 1 and Fe 3+ ; Figure 4 is the fluorescence molar method scatter plot of the novel Fe 3+ fluorescence probe L prepared in Example 1 and Fe 3+ ; Figure 5 is the fluorescence anti-interference diagram of the novel Fe 3+ fluorescence probe L prepared in Example 1 for Fe 3+ in different cations; Figure 6 The novel Fe-detecting 3+ fluorescent probe L prepared in Example 1, the novel Fe-detecting 3+ fluorescent probe L and Fe 2+ , Fe 3 + , Mg 2+ , Na + , Hg 2+ , Ce 3+ , Co 2+ , Cd 2+ , Ni 2+ , Ba 2+ , Pb 2+ , Cu 2+ , K + , Ag + , Zn 2+ , Y 3+ , Al 3+ , Sr 2+ , Ca 2+ , Mn 2+ Application diagram on test paper. Specific implementation manner

[0014] To better understand the present invention, the content of the present invention will be further clarified below in conjunction with embodiments. However, the content of the present invention is not limited to the following embodiments only. Example 1

[0015] Rhodamine 6G and ethylenediamine were reacted at a molar ratio of 1:1 in an ethanol solution at 78 °C and refluxed for 5 hours. After filtration, the solid product was washed with ethanol until white to obtain Product 1. Product 1 was reacted with 2,3,4-trihydroxybenzaldehyde in an equal ratio and refluxed in an ethanol solution at 78 °C for 4 hours. After filtration, the solid product was washed with ethanol 2-3 times and then dried and weighed to obtain the target product fluorescent probe L. Finally, the yield was calculated to be 71%. 1 H NMR (400 MHz, DMSO-d 6) δ 13.34 (s, 1H), 7.81 – 7.71 (m, 2H), 7.50 (td, J = 7.8, 6.8, 3.9 Hz, 2H), 7.03 – 6.95 (m, 1H), 6.49 (dd, J = 17.1, 8.5 Hz, 1H), 6.27 (s, 2H), 6.19 (d, J = 8.5 Hz, 1H), 6.07 (s, 2H), 5.10 (t, J = 5.4 Hz, 2H), 3.11 (ddd, J = 11.6, 7.2, 5.1 Hz, 6H), 1.81 (s, 6H), 1.21 (t, J = 7.1 Hz, 6H). 13 C NMR (101 MHz, DMSO-d 6 ) δ 167.56, 165.84, 155.46, 153.84, 151.45, 149.17, 148.21, 133.04, 130.79, 128.76, 128.07, 124.12, 123.16, 122.91, 118.87, 111.25, 107.15, 105.11, 96.04, 64.56, 54.34, 37.93, 19.04, 17.47, 14.61. The reaction process formula is as follows: .

[0016] 1. Recognition of cations by the fluorescent probe molecule L Prepare an acetonitrile solution of probe L with a concentration of 1×10 -4 moL / L (0.059 g is fixed in a 100 mL volumetric flask). Sequentially add 100 μL of a solution with a concentration of 1×10 -3 moL / L of Fe 2+ , Fe 3+ , Mg 2+ , Na + , Hg 2+ , Ce 3+ , Co 2+ , Cd 2+ , Ni 2+ , Ba 2+ , Pb 2+ , Cu 2+ , K + , Ag + , Zn 2+ , Y 3+ , Al3+ , Sr 2+ , Ca 2+ , Mn 2+ acetonitrile solutions, and then add 2600 μL of acetonitrile solution to each, with a total volume of 3000 μL. Separately, take another portion of the probe L solution and add only 2700 μL of acetonitrile as a control. Perform fluorescence emission spectroscopy tests on these 21 groups of solutions.

[0017] Under a 365 nm ultraviolet lamp, after adding Fe 3+ , the solution changes from colorless fluorescence to yellow fluorescence, and there is no obvious change in the solutions of other ions ( Figure 1 ). From the fluorescence emission spectrum, when using 450 nm as the excitation wavelength and adding Fe 3+ , an obvious emission peak appears at 526 nm, while no emission peak is produced by other ions ( Figure 2 ).

[0018] 2. Determine the response time of Fe 3+ and the fluorescent probe molecule L Prepare a 300 μL acetonitrile solution of the fluorescent probe molecule L (1×10 -4 moL / L) and a 100 μL acetonitrile solution of Fe 3+ (1×10 -3 moL / L), and finally make up to 3000 mL with acetonitrile. Measure the fluorescence intensity every minute. Select the maximum fluorescence emission wavelength of 526 nm to make a scatter plot.

[0019] As can be seen from Figure 3 , the fluorescence intensity at 526 nm gradually increases with time and reaches the strongest at 15 minutes and then basically remains unchanged, indicating that it has a good response recognition effect on Fe 3+ .

[0020] 3. Determine the complexation ratio of Fe 3+ and the fluorescent probe molecule L The complexation ratio of the probe molecule and the ion is determined by the mole method.

[0021] In the mole method experiment, keep the concentration of the fluorescent probe molecule unchanged, add different volumes of the ion acetonitrile solution to the acetonitrile solution of the fluorescent probe molecule to obtain different concentrations of cations, and perform fluorescence emission spectroscopy tests. Plot the fluorescence intensity on the vertical axis and the ratio of [cation] / [probe molecule] on the horizontal axis. There will be an inclined straight line and a horizontal straight line, and the extension of the two straight lines will produce an intersection point. The ratio corresponding to this point is the complexation ratio of the probe molecule and the cation.

[0022] Determine the fluorescent probe molecule L and Fe 3+Complexation Ratio - Molar Method Experiment Maintain the volume of probe L (1×10 -4 moL / L) at 300 μL and gradually increase the volume of Fe 3+ (1×10 -4 moL / L), change the concentration of Fe 3+ so that it increases from 1 μM to 20 μM, and keep the total solution volume at 3000 μL for fluorescence testing. Plot the fluorescence intensity on the vertical axis against the concentration ratio of Fe 3+ to probe L on the horizontal axis. From Figure 4 it can be seen that there is an inflection point after the inclined straight line, and it becomes a straight line after the inflection point. The position of the inflection point is [Fe 3+ / [L]=1, so the complexation ratio of the fluorescent probe molecule L to Fe 3+ is 1:1.

[0023] 4. Anti - interference Experiment of Cations Prepare 21 groups of 300 μL acetonitrile solutions of fluorescent probe molecule L (1×10 -4 moL / L) and 100 μL of Fe 3+ acetonitrile solution (1×10 -3 moL / L). Sequentially add 100 μL of other cations (Fe 2+ , Fe 3+ , Mg 2+ , Na + , Hg 2+ , Ce 3+ , Co 2+ , Cd 2+ , Ni 2+ , Ba 2+ , Pb 2+ , Cu 2+ , K + , Ag + , Zn 2+ , Y 3+ , Al 3+ , Sr 2+ , Ca 2+ , Mn 2+ ) acetonitrile solution (1×10 -3 moL / L), and finally make up the volume to 3000 μL with acetonitrile. At the same time, measure the fluorescence intensity of the 21 groups of solutions.

[0024] From Figure 5 it can be seen that the black represents the fluorescence response experiment and the red represents the anti - interference experiment. The measured data fluctuates little, indicating that other cations have basically no interference on the response of probe molecule L to Fe 3+ . This shows that probe L has little interference on Fe3+ Specific recognition without interference from other cations and strong anti-interference ability.

[0025] 5. Preparation and detection of test strips with probe molecules Measure 300 μL of the acetonitrile solution of probe molecule L (1×10 -4 moL / L), and add 100 μL of other cations (Fe 2+ , Fe 3+ , Mg 2+ , Na + , Hg 2+ , Ce 3+ , Co 2+ , Cd 2+ , Ni 2+ , Ba 2+ , Pb 2+ , Cu 2+ , K + , Ag + , Zn 2+ , Y 3+ , Al 3+ , Sr 2+ , Ca 2+ , Mn 2+ ) acetonitrile solution (1×10 -3 moL / L), and finally make up the volume to 3000 μL with acetonitrile. For the last group, no cations are added and the volume is directly made up to 3000 μL. Immerse 21 test strips of the same size in these 21 solutions respectively, take them out every 5 - 6 minutes and observe under ultraviolet light.

[0026] In Figure 6 , the fluorescence of the test strip prepared with probe molecule L is weak, and the change in fluorescence of the test strip after adding other cations is not very significant. However, the fluorescence of the test strip added with Fe 3+ will be significantly enhanced. Therefore, probe molecule L can detect Fe 3+ through the test strip. Example 2

[0027] React rhodamine 6G with ethylenediamine in a molar ratio of 1:1 in an ethanol solution at 75°C and reflux for 3 hours. After suction filtration, wash the solid product with ethanol until it is white to obtain product 1. React product 1 with 2,3,4-trihydroxybenzaldehyde in an equal ratio, reflux in an ethanol solution at 75°C for 2 hours. After suction filtration, wash the solid product with ethanol 2 - 3 times and then dry and weigh to obtain the target product fluorescent probe L. Finally, calculate the yield to be 65%. Example 3

[0028] Rhodamine 6G and ethylenediamine were reacted in a molar ratio of 1:1 and placed in an ethanol solution at 80 °C for reflux for 8 hours. After suction filtration, the solid product was washed with ethanol until white to obtain Product 1. Product 1 was reacted with 2,3,4-trihydroxybenzaldehyde in an equal ratio and refluxed in an ethanol solution at 80 °C for 6 hours. After suction filtration, the solid product was washed with ethanol 2-3 times and then dried and weighed to obtain the target product, the fluorescent probe L. Finally, the yield was calculated to be 69%.

[0029] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A new method for detecting Fe 3+ A fluorescent probe, characterized in that Its molecular formula is:

2. The novel Fe detection method according to claim 1 3+ A method for preparing a fluorescent probe, characterized in that: The steps include: (1) Rhodamine 6G is reacted with ethylenediamine to obtain product 1; (2) The product 1 is reacted with 2,3,4-trihydroxybenzaldehyde to detect Fe 3+ Fluorescent probe L; The reaction process is:

3. The novel detection Fe according to claim 2 3+ A method for preparing a fluorescent probe, characterized in that: The reaction temperature in step (1) is 70-80° C., the reaction time is 3-8 h, and the reaction solvent is ethanol.

4. The novel Fe detection method according to claim 2 3+ A method for preparing a fluorescent probe, characterized in that: The reaction temperature in step (2) is 70-80° C., the reaction time is 2-6 h, and the reaction solvent is ethanol.

5. The novel Fe detection method according to claim 1 3+ Fluorescent probe or the novel Fe detection method according to any one of claims 2 to 4 3+ A novel fluorescent probe for detecting Fe 3+ The application of fluorescent probe is characterized by: The application process includes: Configure new Fe detection 3+ Fluorescent probe solution, Fe 2+ , Fe 3+ ,Mg 2+ , Na + , Hg 2+ , Ce 3+ ,Co 2+ , Cd 2+ , Ni 2 + , Ba 2+ , Pb 2+ , Cu 2+ , K + , Ag + , Zn 2+ , Y 3+ , Al 3+ , Sr. 2+ , Ca 2+ , Mn 2+ solution and measure the fluorescence intensity.

6. The novel Fe detection method according to claim 5 3+ The application of fluorescent probe is characterized by: The novel Fe 3+ The solvent of the fluorescent probe solution is acetonitrile. 3+ The concentration of the fluorescent probe solution was 1×10 -4 moL / L.

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