A fluorescent probe constructed with a symmetrical tetramethyl six-membered cucurbit ring and its application in the detection of p-nitrophenol
By preparing a fluorescent probe constructed of a symmetrical tetramethyl hexacyclic ring, the problems of complex and high cost in detecting p-nitrophenol in existing technologies were solved, and a simple, rapid and sensitive detection of p-nitrophenol in water was achieved, which has qualitative and quantitative capabilities and maintains high selectivity in complex environments.
Patent Information
- Application Number
- CN202311253877.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-09-27
- Publication Date
- 2025-09-12
- Estimated Expiration
- 2043-09-27
AI Technical Summary
The existing methods for detecting p-nitrophenol are complex, costly, and require high technical skills, making it difficult to achieve simple, rapid, and sensitive detection.
A fluorescent probe constructed with a symmetrical tetramethyl six-membered cucurbit ring was prepared by mixing TMeQ[6] and TBZ aqueous solution to detect p-nitrophenol in water using fluorescence spectroscopy.
It achieves simple, sensitive, and rapid detection of p-nitrophenol in water with both qualitative and quantitative capabilities and maintains high selectivity in the presence of other phenolic interfering compounds.
Smart Images
Figure CN117431055B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a fluorescent probe for detecting p-nitrophenol and application thereof, in particular to the preparation of a fluorescent probe constructed with a symmetrical tetramethyl six-membered cucurbitacin ring and thiabendazole and application thereof in the detection of p-nitrophenol. Background Art
[0002] Para-nitrophenol (p-NP) is an organic synthetic raw material widely used as an intermediate in fine chemicals such as pharmaceuticals, dyes, and pesticides. It is also used in developers and leather preservatives. However, it is highly toxic, can cause allergies through skin and respiratory absorption, and can cause poisoning if accumulated in the human body. p-NP is highly water-soluble and has been detected in agricultural soil, surface water, groundwater, rainwater, air, activated sludge, and industrial wastewater. Due to the aromatic rings in its molecular structure, p-NP is relatively stable, difficult to biodegrade, and has a long half-life in the natural environment, posing a threat to the ecological environment. It has been listed as a priority pollutant in my country's water supply.
[0003] Currently, common methods for detecting p-nitrophenol include gas chromatography, liquid chromatography, high-performance liquid chromatography, and mass spectrometry. These methods suffer from complex sample preparation, high testing costs, and demanding technical expertise. Therefore, developing a simple, rapid, and sensitive analytical method to accurately and effectively detect p-nitrophenol is of great significance for human health protection and environmental control. Summary of the Invention
[0004] The technical problem to be solved by the present invention is to provide a preparation method of a fluorescent probe constructed with a symmetrical tetramethyl six-membered cucurbit ring and its application in detecting p-nitrophenol. The supramolecular fluorescent probe of the present invention can simply, sensitively and rapidly detect p-nitrophenol in water.
[0005] The technical solution of the present invention is: a fluorescent probe constructed with a symmetrical tetramethyl six-membered cucurbit ring, the chemical structure of which is as follows:
[0006]
[0007] in: represents the symmetrical tetramethyl six-membered cucurbit ring TMeQ[6], It is thiabendazole.
[0008] The fluorescent probe was prepared from TMeQ[6] aqueous solution and TBZ aqueous solution.
[0009] The molar ratio of TMeQ[6] to TBZ is 1:1.
[0010] The method comprises the following steps: (1) dissolving TMeQ[6] in water to obtain a TMeQ[6] aqueous solution; (2) dissolving TBZ in water to obtain a TBZ aqueous solution; and (3) mixing the TMeQ[6] and TBZ aqueous solutions in a molar ratio of 1:1 and reacting them at room temperature to obtain a supramolecular fluorescent probe. The reaction time is 5-10 minutes.
[0011] The fluorescent probe constructed with the symmetrical tetramethyl six-membered cucurbitacin ring is used in detecting p-nitrophenol.
[0012] The fluorescent probe constructed with a symmetrical tetramethyl hexacyclic ring is used to detect p-nitrophenol. The detection method is as follows: (1) preparing a fluorescent probe standard solution, fixing the excitation wavelength at 298 nm to perform fluorescence emission spectrum measurement, and drawing a fluorescence spectrum graph; (2) adding an aqueous solution of a sample to be detected to the fluorescent probe standard solution, leaving it for 5-10 minutes, fixing the excitation wavelength at 298 nm to perform fluorescence emission spectrum measurement, and drawing a fluorescence spectrum graph; (3) calculating the fluorescence emission spectrum intensity change ΔI of the sample to be detected at 354 nm based on the fluorescence spectrum change curves of steps (1) and (2), thereby detecting p-nitrophenol in water.
[0013] The concentration of the probe standard solution is 3×10 -5 mol / L.
[0014] The detection limit of the fluorescent probe for p-nitrophenol in water is 4.86×10 -6 mol / L.
[0015] Beneficial effects of the present invention: 1. The present invention produces a novel supramolecular fluorescent probe constructed with a symmetrical tetramethyl six-membered cucurbit ring, which can detect p-nitrophenol in water.
[0016] 2. The fluorescent probe detection method of the present invention has the advantages of high sensitivity, simple sample processing, convenient operation, rapid determination and real-time detection.
[0017] 3. The fluorescent probe provided by the present invention can not only perform qualitative detection of p-nitrophenol in water, but also perform quantitative detection of p-nitrophenol in water according to the different changes in fluorescence intensity.
[0018] 4. The present invention uses ultraviolet absorption spectrometry, fluorescence spectroscopy and nuclear magnetic titration to explore the appropriate molar ratio of TMeQ[6] and TBZ to form a fluorescent probe (see Appendix Figure 2 and attached Figure 3 ).
[0019] 5. The present invention studies whether the fluorescent probe can selectively detect p-nitrophenol (attached) in the presence of 15 kinds of phenols through anti-interference experiments. Figure 5), the 15 phenols are: o-cresol (o-Cres), m-cresol (m-Cres), p-cresol (p-Cres), m-aminophenol (m-AP), o-aminophenol (o-AP), p-aminophenol (p-AP), o-triphenol (Pyro), 2,4-diaminophenol (2,4-AP), 2-bromophenol (2-BP), 3-bromophenol (3-BP), 4-bromophenol (4-BP), hydroquinone (Hydro), pyrogallol (PG), o-nitrophenol (o-NP), and m-nitrophenol (m-NP). The results show that the supramolecular fluorescent probe of the present invention has strong anti-interference ability in the detection of p-nitrophenol.
[0020] 6. The present invention uses a concentration of 3.0×10 -5 mol / L fluorescent probe was used as a standard solution, and solutions containing different concentrations of p-nitrophenol were added thereto for detection. Different concentrations of p-nitrophenol could reduce the fluorescence of the fluorescent probe solution to varying degrees. The linear range of the fluorescence response was (1.8-5.4)×10 -5 mol / L, and the detection limit of the fluorescent probe for p-nitrophenol was 4.86×10 -6 mol / L(Attached Figure 6 ). BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 The molecular structures of TMeQ[6], TBZ, and p-nitrophenol;
[0022] Figure 2 UV spectra and fluorescence spectra of TMeQ[6] and TBZ;
[0023] Figure 3 The NMR titration and action mode diagram of TMeQ[6] and TBZ; where: (a) pure TBZ; (b) 1.0 equivalent TBZ; (c) TMeQ[6];
[0024] Figure 4 The fluorescence response diagram of the fluorescent probe to 16 phenols;
[0025] Figure 5 The graph shows the change in fluorescence intensity after adding different phenols to the probe-p-nitrophenol system; the tall bar graph shows the fluorescence intensity graph of the fluorescent probe after adding 15 kinds of phenols; the short bar graph shows the fluorescence intensity graph of the fluorescent probe after adding 15 kinds of phenols and then adding p-NP;
[0026] Figure 6 Fluorescence spectra of the fluorescent probe standard solution when solutions containing p-nitrophenol at different concentrations were added (a); curve analysis (b); and detection limit (c). DETAILED DESCRIPTION
[0027] The present invention will be further described below with reference to the examples, but they are not intended to limit the present invention.
[0028] Example 1
[0029] The preparation method of the reagent in this specific embodiment:
[0030] (1) Accurately weigh an appropriate amount of TMeQ[6], dissolve it in secondary water, sonicate it, transfer it to a 100 mL volumetric flask, and adjust the volume to obtain a concentration of 1.0×10 -4 mol / L TMeQ[6] solution;
[0031] (2) Accurately weigh an appropriate amount of TBZ, dissolve it in secondary water, sonicate it, transfer it to a 10 mL volumetric flask, and adjust the volume to a concentration of 1.0 × 10 -3 mol / L compound TBZ solution;
[0032] (3) Preparation of p-nitrophenol standard solution: Accurately weigh the required analytically pure p-nitrophenol standard and dissolve it in secondary water to obtain a concentration of 2.0×10 -3 mol / L p-nitrophenol standard solution.
[0033] Example 2
[0034] A method for preparing a fluorescent probe solution constructed with a symmetrical tetramethyl six-membered cucurbit ring is as follows:
[0035] (1) The TMeQ[6] solution and the TBZ solution in Example 1 were mixed in a molar ratio of 1:1 and allowed to react at room temperature for 5-10 minutes to obtain the fluorescent probe solution;
[0036] (2) Dilute the supramolecular fluorescent probe solution with secondary water to a concentration of 3×10 -5 mol / L fluorescent probe standard solution.
[0037] Example 3
[0038] A specific operation for determining p-nitrophenol:
[0039] (1) Determination of standard curve:
[0040] Take 8 10mL volumetric flasks and add 300μL of 1.0×10 -3 mol / L TBZ solution and 3000 μL of 1.0×10 -4 mol / L TMeQ[6] solution was mixed evenly to form a probe, and then 2.0×10 -30 μL, 90.0 μL, 180.0 μL, 270.0 μL, 360.0 μL, 450.0 μL, 540 μL, and 630.0 μL of mol / L p-nitrophenol standard solution were made up to volume with secondary aqueous solution, shaken and set aside. The fluorescence emission spectrum was determined with a fixed excitation wavelength of 298 nm. The concentration of p-nitrophenol was used as the horizontal axis, and the difference (I0-I) between the probe fluorescence emission intensity (I0) at 354 nm and the fluorescence emission intensity (I) of different concentrations of p-nitrophenol was used as the vertical axis to draw a standard curve. The detection limit of p-nitrophenol by the fluorescent probe was calculated based on the slope s of the standard curve and the standard deviation σ of 11 blank values. The formula is LOD = 3σ / s;
[0041] (2) Sample testing:
[0042] Take an aqueous solution containing p-nitrophenol but with unknown concentration and add it to the prepared fluorescent probe standard solution, controlling its concentration to not exceed the linear range of (1.8-5.4)×10 -5 mol / L, and under the excitation wavelength of 298nm, the fluorescence intensity at 354nm is significantly weakened, which means that the water sample contains p-nitrophenol;
[0043] Take the aqueous solution without p-nitrophenol and add it to the prepared fluorescent probe standard solution, controlling its concentration to not exceed the linear range of (1.8-5.4)×10 -5 mol / L, and under an excitation wavelength of 298 nm, there is no obvious change in fluorescence intensity at 354 nm, which means that the water sample does not contain p-nitrophenol.
[0044] Example 4
[0045] Another specific operation of measuring p-nitrophenol of the present invention is:
[0046] (1) Determination of standard curve:
[0047] Take a quartz fluorescence cuvette and add 3.00×10 -5 mol / L fluorescent probe solution 3000 μL, then accurately add 2.0×10 -39.0 μL of p-nitrophenol standard solution of 1000 μL mol / L was mixed, and fixing the excitation wavelength to 298nm was used to carry out fluorescence emission spectrum measurement. According to the above operation, 9.0 μL p-nitrophenol standard solution was constantly added to the above-mentioned 3000 μL probe solution, and under the excitation wavelength of 298nm, a series of fluorescence curves were measured, until the fluorescence curve ordinate value changed slowly, the titration operation could be stopped. The p-nitrophenol concentration was then used as the abscissa, and the difference (I0-I) between the 354nm place probe fluorescence emission intensity (I0) and the fluorescence emission intensity (I) after adding different concentrations of p-nitrophenol was used as the ordinate to obtain a standard curve. By the slope s of the standard curve and the standard deviation σ of 11 blank values, the detection limit of p-nitrobenzene by the fluorescence probe was calculated, and the formula was LOD=3σ / s.
[0048] (2) Sample testing:
[0049] Take an aqueous solution containing an unknown concentration of p-nitrophenol, add it to the prepared fluorescent probe standard solution, and observe the fluorescence intensity at 354nm under an excitation wavelength of 298nm. If there is a significant weakening phenomenon, it means that the water sample contains p-nitrophenol. If there is no obvious change in fluorescence intensity, it means that the water sample does not contain p-nitrophenol or the content is lower than the detection limit of the probe.
[0050] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, can make equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention, which should be covered by the scope of protection of the present invention.
Claims
1. Application of a fluorescent probe constructed with a symmetrical tetramethyl six-membered cucurbit ring in the detection of p-nitrophenol, wherein the chemical structure of the fluorescent probe is as follows: ； in: represents the symmetrical tetramethyl six-membered cucurbit ring TMeQ[6], It is thiabendazole.
2. The use of a fluorescent probe constructed with a symmetrical tetramethyl six-membered cucurbit ring according to claim 1 in detecting p-nitrophenol, characterized in that: The detection method is as follows: (1) preparing a fluorescent probe standard solution, fixing the excitation wavelength at 298 nm to perform fluorescence emission spectrum measurement, and drawing a fluorescence spectrum graph; (2) adding the aqueous solution of the sample to be tested to the fluorescent probe standard solution, leaving it for 5-10 minutes, fixing the excitation wavelength at 298 nm to perform fluorescence emission spectrum measurement, and drawing a fluorescence spectrum graph; (3) calculating the fluorescence emission spectrum intensity change ΔI of the sample to be tested at 354 nm based on the fluorescence spectrum change curves of steps (1) and (2), and thus the p-nitrophenol in the water can be detected.
3. The use of a fluorescent probe constructed with a symmetrical tetramethyl six-membered cucurbit ring according to claim 2 in detecting p-nitrophenol, characterized in that: The concentration of the probe standard solution is 3×10 -5 mol / L.
4. The use of a fluorescent probe constructed with a symmetrical tetramethyl six-membered cucurbit ring in detecting p-nitrophenol according to claim 2, characterized in that: The detection limit of the fluorescent probe for p-nitrophenol in water is 4.86×10 -6 mol / L.