Organic fluorescent probe, application of organic fluorescent probe to observation or measurement of solution viscosity and viscosity detection device
By using an organic fluorescent probe to detect the absorbance and fluorescence intensity of a solution, combined with a fluorescence spectrometer, the problems of contact consumption and quantitative analysis in existing viscosity detection methods are solved, achieving micro-quantitative and precise viscosity detection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SUZHOU HANNA MATERIAL TECH CO LTD
- Filing Date
- 2025-12-16
- Publication Date
- 2026-05-08
AI Technical Summary
Existing viscosity detection methods require direct contact with the solution to be tested, resulting in high consumption and difficulty in reuse. Furthermore, fluorescent probes are mostly used for qualitative judgment and lack quantitative analysis capabilities.
By using organic fluorescent probes to detect changes in absorbance and fluorescence intensity of the solution, combined with a fluorescence spectrometer, a micro-quantitative analysis of solution viscosity can be achieved.
It enables trace viscosity detection without contact with the solution, accurately calculates viscosity values, and improves detection accuracy and efficiency.
Smart Images
Figure CN121990974A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of fluorescent probes, and particularly relates to an organic fluorescent probe, its application in observing or measuring solution viscosity, and a viscosity detection device. Background Technology
[0002] Viscosity is a physical quantity that measures a fluid's resistance to deformation, reflecting the internal friction generated during fluid flow. It is also a key indicator for evaluating the quality of some finished or semi-finished products. Currently, the mainstream viscosity testing method is the viscometer method, with commonly used instruments including falling ball and rotational viscometers. These methods typically require direct contact between the viscometer and the solution being tested, which not only consumes a large amount of solution during the testing process but also makes it difficult to reuse the solution after contact with the viscometer. Therefore, there is an urgent need to develop a liquid viscosity testing technology that does not require contact with the solution and only requires a small amount of the test liquid.
[0003] Fluorescence detection technology, as a microanalysis method, possesses advantages such as high sensitivity, strong selectivity, ease of operation, and rapid response. Solution viscosity detection based on fluorescent probes is an effective approach for microanalysis. Currently, research on viscosity-responsive fluorescent probes largely focuses on qualitatively determining solution viscosity levels through changes in fluorescence intensity. For example, invention patent CN113845462 discloses a fluorescent probe molecule composed of indole and indole iodide, which responds to solution viscosity and allows for qualitative determination of viscosity levels through changes in fluorescence intensity; however, it does not address the implementation of quantitative analysis. Furthermore, there are few reports on observing solution viscosity using absorbance methods, which is detrimental to viscosity detection. Summary of the Invention
[0004] The main technical problem solved by this invention is to provide an organic fluorescent probe, its application in observing or measuring solution viscosity, and a viscosity detection device. The organic fluorescent probe of this invention, through a viscosity response mechanism, can observe the viscosity of a solution by detecting changes in the absorbance of the solution containing the organic fluorescent probe, and can also calculate the viscosity of the solution through the fluorescence intensity value, thereby realizing micro-quantitative analysis of solution viscosity detection.
[0005] To solve the above-mentioned technical problems, one technical solution adopted by the present invention is to provide an organic fluorescent probe, the structural formula of which is:
[0006] R is an iodoethanol group or a methyl group.
[0007] In a preferred embodiment of the present invention, the synthetic route of the organic fluorescent probe is as follows:
[0008] ,
[0009] Organic fluorescent probes were synthesized from compounds 1 and 2 via a Knoevenagel reaction with a molar ratio of 1:(1-1.2), a temperature of 85-95℃, and a reflux time of 6-10 h. The catalyst in the Knoevenagel reaction was an organic base. The resulting organic fluorescent probes were purified by column chromatography.
[0010] An application of observing solution viscosity based on an organic fluorescent probe by means of absorbance involves dissolving the organic fluorescent probe in the solution to be tested and observing the solution viscosity by measuring the absorbance of the solution.
[0011] An application for measuring solution viscosity based on an organic fluorescent probe involves dissolving the organic fluorescent probe in the test solution and then detecting the fluorescence intensity I of the solution. F The viscosity η of the solution is then calculated according to the equation, where the viscosity η ≥ 1 cP. If the viscosity of the test solution is less than 1 cP, the accuracy of the viscosity measurement is low. This is presumably due to the long-chain structure of the organic fluorescent probe, which may reduce its solubility in solvents with a viscosity less than 1 cP. In such cases, the concentration in the solution is too low, resulting in lower fluorescence intensity and increased measurement error.
[0012] In a preferred embodiment of the present invention, the viscosity range of the solution is 1 cP-1000 cP.
[0013] In a preferred embodiment of the present invention, the concentration of the organic fluorescent probe in the solution is 5-15 μM. If the concentration of the organic fluorescent probe in the solution is too high, fluorescence quenching will occur; if the concentration is too low, the fluorescence intensity will decrease, increasing the measurement error.
[0014] In a preferred embodiment of the present invention, the concentration of the organic fluorescent probe in the solution is 10 μM.
[0015] A viscosity detection device based on the above application is a fluorescence spectrometer, which includes a memory and a processor. The memory stores a calculation program, and when executed by the processor, the calculation program can perform the following steps: [The text abruptly ends here, so the translation stops.] F Substitute into equation logI F The viscosity η of the solution is calculated from 1.95 + 0.86logη. In practice, this calculation program can be added to the memory of an existing fluorescence spectrometer. By adding the calculation program to the solution to be tested, the viscosity of the solution can be determined based on the viscosity response mechanism of the organic fluorescent probe.
[0016] A viscosity detection device based on the above application includes a fluorescence spectrometer and a peripheral controller electrically connected to the fluorescence spectrometer. The peripheral controller includes a memory and a processor. The fluorescence spectrometer is used to measure the fluorescence intensity I of the solution. F and fluorescence intensity I F The value is transmitted to the peripheral controller; the memory stores a calculation program, which, when executed by the processor, performs the following steps: [The text abruptly shifts to a different topic] ...the fluorescence intensity I of the solution... F Substitute into equation logI F The viscosity η of the solution is calculated from 1.95 + 0.86logη. In practical implementation, an external controller can be connected to the existing fluorescence spectrometer to determine the viscosity of the solution through the viscosity response mechanism of the organic fluorescent probe.
[0017] The beneficial effects of this invention are as follows: This invention provides an organic fluorescent probe, its application in observing or measuring solution viscosity, and a viscosity detection device. The organic fluorescent probe of this invention, through a viscosity response mechanism, can observe the viscosity of a solution by detecting changes in the absorbance of the solution, and can also calculate the viscosity of the solution through fluorescence intensity values, thereby achieving micro-quantitative analysis of solution viscosity detection. Attached Figure Description
[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:
[0019] Figure 1 The hydrogen spectrum of the organic fluorescent probe CP;
[0020] Figure 2 The absorption spectrum (A) and fluorescence spectrum (B) of the organic fluorescent probe CP in different solvents are shown.
[0021] Figure 3 The absorption spectra of the organic fluorescent probe CP in mixtures of water and glycerol of different viscosities are shown.
[0022] Figure 4 The fluorescence spectra of the organic fluorescent probe CP in mixtures of water and glycerol of different viscosities are shown in (A). Figure 4 (B) is with Figure 4 The corresponding fluorescence intensity fitting curves are shown in Figure (A).
[0023] Figure 5 (A) shows the absorption spectra of the organic fluorescent probe CP (10 μM) in buffer solutions at different pH values. Figure 5(B) shows the fluorescence spectra of the organic fluorescent probe CP (10 μM) in buffer solutions at different pH values;
[0024] Figure 6 The values in the table represent the fluorescence intensities of the organic fluorescent probe CP (10 μM) at the points of maximum fluorescence intensity in different ionic solutions, where 1. Control, 2. K. + 3.Na + 4.Zn 2+ ,5.Ca 2+ 6.F - 7.Cl - ,8.Br - 9.HCO3 - ,10.NO3 - 11. NO 2- 12.HPO4 2- 13.CO3 2- ,14.SO3 2- ,15.PO4 3- ,16.Cys,17.glucose,18.H2O2. Detailed Implementation
[0025] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0026] Please see Figures 1-6 As shown, all substances used in each embodiment were commercially available products. 2-Pyrenecaraldehyde, among others, was purchased from Bailingwei Technology Co., Ltd. The absorption spectroscopy was performed using a Hitachi U-2910 spectrophotometer; the fluorescence spectroscopy was performed using a Hitachi F-2700 spectrophotometer.
[0027] Example 1
[0028] Organic fluorescent probes, abbreviated as CP, are synthesized as follows:
[0029] Compound 1 (1 mmol) and Compound 2 (1 mmol) were dissolved in 20 mL of methanol and stirred in a flask for 1 h. Five drops of piperidine were added. After stirring, the mixture was refluxed at 85 °C for 8 h, cooled to room temperature, and washed with petroleum ether. The solution was purified by column chromatography using a mixture of CH2Cl2 and CH3OH (volume ratio of CH2Cl2 to CH3OH 10:1 to 6:1). The resulting red solid was the organic fluorescent probe, chemically named (E)-3-(2-hydroxyvinyl)-1,1-dimethyl-2-(2-(pyrene-1)vinyl)-1H-benzoindole-3-iodide, abbreviated as CP. Analysis of the proton NMR spectrum of the organic fluorescent probe confirmed its structure. The organic fluorescent probe is a small organic molecule fluorescent probe, and the characterization results are as follows:
[0030] 1 H NMR (400 MHz, DMSO-d6), δ (ppm): 8.47 (q, J=8.0 Hz, 2H), 8.31 (q,J=8.0 Hz, 4H), 8.21 (s, 2H), 8.04-8.12 (m, 2H), 7.92 (t, J=14.0 Hz, 2H), 7.84(d, J=8.0 Hz, 1H), 7.48 (t, J=8.0 Hz, 1H), 7.31-7.39 (m, 2H), 6.71 (d, J=8.0Hz, 1H), 3.91-4.09 (m, 3H), 3.56-3.63 (m, 2H), 1.82 (s, 3H), 1.41 (s, 3H).
[0031] The proton spectrum of CP, such as Figure 1 As shown.
[0032] Example 2
[0033] Experiments to test the photophysical properties of CP in different solvents.
[0034] Test solutions containing 10 μM CP were prepared using different types of organic solvents. The absorption and fluorescence emission spectra of these solutions were then measured using a UV spectrophotometer and a fluorescence spectrometer. The results are shown below. Figure 2 .
[0035] from Figure 2 The results show that the organic fluorescent probe exhibits higher absorbance and fluorescence intensity in pure glycerol, but lower absorbance and fluorescence intensity in other low-viscosity solvents, indicating that the organic fluorescent probe is sensitive to viscosity.
[0036] Example 3
[0037] An experiment to measure the absorbance of CP in response to viscosity.
[0038] H₂O and glycerol were mixed in different proportions to prepare mixed solvents with different viscosities. Then, CP was added to each solvent to prepare test solutions containing 10 μM CP. The handwashing spectra of the above solutions were measured using a UV-Vis absorption spectrometer to obtain the corresponding curves.
[0039] exist Figure 3 In the study, the absorbance of the organic fluorescent probe gradually increased with the increase of the glycerol content, indicating that the organic fluorescent probe responded significantly to changes in viscosity. Therefore, the viscosity of the solution can be observed by measuring the absorbance of CP in different solutions.
[0040] Example 4
[0041] Viscosity-responsive fluorescence test of CP.
[0042] H₂O and glycerol were mixed in different proportions to prepare mixed solvents with different viscosities. Then, CP was added to each solvent to prepare test solutions containing 10 μM CP. The spectra of the above solutions were measured using a fluorescence spectrometer to obtain the corresponding curves, and then fitted to obtain the fitted curves.
[0043] exist Figure 4 In (A), as the glycerol content increases, the fluorescence intensity of the organic fluorescent probe gradually increases, indicating that the organic fluorescent probe responds significantly to changes in viscosity. From Figure 4 As can be seen from (B) in the image, the fluorescence intensity I of the organic fluorescent probe CP is... F The viscosity η conforms to the Förster–Hoffmann equation, and the equation obtained by fitting is logI. F =1.95 + 0.86logη. Therefore, the viscosity of the solution can be obtained by testing the fluorescence intensity of CP in different solutions.
[0044] Example 5
[0045] pH-responsive fluorescence test of CP.
[0046] Experimental methods:
[0047] (1) Take the CP prepared in Example 1 and prepare a probe stock solution with a concentration of 1 mM using DMSO;
[0048] (2) Prepare PBS solutions with different pH values (pH=3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0).
[0049] (3) Add the probe stock solution prepared in step (1) to the solutions with different pH values prepared in step (2) respectively to prepare test solutions, so that the final concentration of fluorescent probe TN in each solution is 10 μM.
[0050] (4) The absorption spectrum and fluorescence emission spectrum of the above solution were tested using a UV-Vis spectrophotometer and a fluorescence spectrometer to obtain the corresponding curves.
[0051] The absorption spectrum of the above solution was measured using a UV spectrophotometer, see below. Figure 5 A. Its fluorescence emission spectrum was measured using a fluorescence spectrometer, see... Figure 5 B.
[0052] As shown in the figure, the absorbance and fluorescence intensity do not change much with the increase of pH value, indicating that the probe can observe the viscosity of the solution in complex pH environments.
[0053] Example 6
[0054] Fluorescence testing of CP in different ions.
[0055] Experimental methods:
[0056] (1) Take the CP prepared in Example 1 and prepare a probe stock solution with a concentration of 1 mM using DMSO;
[0057] (2) Prepare aqueous solutions of different ions;
[0058] (3) Add the probe stock solution prepared in step (1) to the solutions with different pH values prepared in step (2) respectively to prepare test solutions, so that the final concentration of fluorescent probe CP in each solution is 10 μM.
[0059] (4) Test the fluorescence emission spectrum of the above solution with a fluorescence spectrometer, and take the maximum value of the fluorescence intensity to obtain the corresponding curve.
[0060] Depend on Figure 6 It is evident that the fluorescence intensity of the probe does not change significantly in different ions, indicating that the probe can specifically observe solution viscosity in complex environments.
[0061] In summary, this invention discloses an organic fluorescent probe, its application in observing or measuring solution viscosity, and a viscosity detection device. The organic fluorescent probe of this invention, through a viscosity response mechanism, can observe the viscosity of a solution by detecting changes in the absorbance of the solution, and can also calculate the viscosity of the solution through fluorescence intensity values, thereby achieving micro-quantitative analysis of solution viscosity detection.
[0062] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.
Claims
1. An organic fluorescent probe, characterized in that, The structural formula of the organic fluorescent probe is: R is an iodoethanol group or a methyl group.
2. The organic fluorescent probe according to claim 1, characterized in that, The synthetic route of the organic fluorescent probe is as follows: ， Organic fluorescent probes were synthesized from compounds 1 and 2 via a Knoevenagel reaction with a molar ratio of 1:(1-1.2), a temperature of 85-95℃, and a reflux time of 6-10 h. The catalyst in the Knoevenagel reaction was an organic base. The resulting organic fluorescent probes were purified by column chromatography.
3. An application of the organic fluorescent probe of claim 1 to observe solution viscosity by means of absorbance, characterized in that, The organic fluorescent probe is dissolved in the test solution, and the viscosity of the solution is observed by measuring the absorbance of the solution.
4. An application of the organic fluorescent probe of claim 1 for measuring solution viscosity, characterized in that, The organic fluorescent probe was dissolved in the test solution, and then the fluorescence intensity I of the solution was detected. F Then, the viscosity η of the solution is calculated according to the equation, wherein the viscosity η of the solution is ≥ 1cP.
5. The application according to claim 4, characterized in that, The viscosity range of the solution is 1 cP-1000 cP.
6. The application according to claim 4, characterized in that, The concentration of the organic fluorescent probe in the solution is 5-15 μM.
7. The application according to claim 6, characterized in that, The concentration of the organic fluorescent probe in the solution is 10 μM.
8. A viscosity detection device according to any one of claims 3-7, wherein the viscosity detection device is a fluorescence spectrometer, the fluorescence spectrometer comprising a memory and a processor, characterized in that, The memory stores a calculation program, which, when executed by the processor, performs the following steps: [The program calculates the fluorescence intensity I of the measured solution]. F Substitute into equation logI F The viscosity η of the solution is calculated from η = 1.95 + 0.86logη.
9. A viscosity detection device for any one of claims 4-7, characterized in that, The system includes a fluorescence spectrometer and a peripheral controller electrically connected to the fluorescence spectrometer, the peripheral controller including a memory and a processor, characterized in that the fluorescence spectrometer is used to measure the fluorescence intensity I of a solution. F and fluorescence intensity I F The value is transmitted to the peripheral controller; the memory stores a calculation program, which, when executed by the processor, performs the following steps: [The text abruptly shifts to a different topic] ...the fluorescence intensity I of the solution... F Substitute into equation logI F The viscosity η of the solution is calculated from =1.95+0.86logη.