A rapid visual detection method of picric acid based on water-soluble perylene imide derivatives

Abstract

The application relates to the field of picric acid detection, and discloses a rapid visual detection method based on a perylene imide derivative. Specifically, a method for detecting picric acid is disclosed, wherein a perylene imide derivative with a structure shown in formula (I) is used as a probe. The probe has good water solubility, and can realize high-sensitivity, specific and visual detection of picric acid. The detection method provided by the application has high detection efficiency and sensitivity.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of picric acid detection, and particularly relates to a rapid visual detection method for picric acid based on water-soluble perylene imide derivatives. BACKGROUND

[0002] 2,4,6-trinitrophenol (TNP), also known as picric acid, is in a yellow crystalline state at room temperature. TNP is a very dangerous nitroaromatic organic compound with great explosive power and is a common component of military explosives. At the same time, TNP is also widely used in today's society: in the field of agriculture, it is often used as a fungicide; in the field of medicine, it can be used for animal marking, etc.

[0003] However, TNP contains phenolic hydroxyl groups and has good water solubility, and is easily left in large quantities in the environment, polluting soil and groundwater, and then directly or through biological enrichment affecting human bodies. TNP can cause inflammation, poisoning, dizziness, fever and other symptoms, and has strong hepatotoxicity and hemotoxicity. It can be seen that TNP is extremely harmful to public safety, the natural environment and human health. Therefore, it is necessary to establish a TNP detection method with high sensitivity and strong specificity, especially a direct rapid visual detection method for TNP in water. SUMMARY

[0004] Therefore, the present application aims to solve the technical problem of providing a rapid visual detection method for picric acid based on water-soluble perylene imide derivatives, and specifically discloses a method for detecting picric acid, which overcomes the defects of low detection efficiency and low sensitivity in the prior art.

[0005] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0006] Firstly, the present application provides the application of a perylene imide derivative represented by formula (I) in the detection of picric acid:

[0007]

[0008] The perylene imide derivative represented by formula (I) has good water solubility and can detect picric acid with high sensitivity and specificity, and has obvious specificity and anti-interference ability in detection.

[0009] The perylene imide derivative of the structure shown in formula (I) of the present application exhibits different states to external stimuli in solution and aggregation state, thereby causing changes in optical properties, such as changes in solution color and fluorescence opening or quenching phenomenon. Therefore, when the above-mentioned perylene imide derivative is used for the detection of picric acid, the fluorescence response effect can be achieved, that is, the fluorescence of the perylene imide derivative is quenched, and the quenching effect is visible to the naked eye under ultraviolet light irradiation. At the same time, the color of the perylene imide derivative solution changes, and this effect can be more obviously embodied by extracting the RGB value.

[0010] In addition, the detection limit of the above-mentioned perylene imide derivative is as low as 9 nmol / L, and the visualization effect in the solution is obvious, and the visualization detection limit is as low as 10 μmol / L.

[0011] The perylene imide derivative provided by the present application has excellent picric acid detection performance, which may be based on the following principle: the perylene imide derivative of the present application can recognize picric acid through multiple non-covalent interactions, and picric acid can induce fluorescence quenching of the perylene imide derivative. This process is mainly based on electrostatic interaction, accompanied by π-π stacking, charge transfer, hydrophobic interaction and other synergistic effects.

[0012] The source of the above-mentioned perylene imide derivative of the structure shown in formula (I) is not particularly limited, and can be generally commercially available or prepared according to methods well known to those skilled in the art.

[0013] Secondly, the present application provides a reagent, test paper or kit for detecting picric acid, comprising the above-mentioned perylene imide derivative or the perylene imide derivative prepared by the above-mentioned preparation method.

[0014] Thirdly, the present application provides a quantitative detection method based on water-soluble perylene imide derivative. Specifically, the present application provides a method for detecting picric acid, using the above-mentioned perylene imide derivative or the perylene imide derivative prepared by the above-mentioned preparation method as a probe.

[0015] Preferably, the concentration of the probe is 2 μmol / L.

[0016] Specifically, the specific detection method is as follows: in 10 mmol / L pH=7.0 4-hydroxyethyl piperazine ethanesulfonic acid (HEPES) buffer solution, the above-mentioned probe concentration is 2 μmol / L for the spectral test of picric acid, and the excitation wavelength is 440 nm during detection. The fluorescence intensity at the emission wavelength of 490 nm is selected to calculate the fluorescence quenching efficiency of the probe, and the standard curve for detection is established by taking the concentration of picric acid as the abscissa and the fluorescence quenching efficiency of the probe as the ordinate.

[0017] Fourthly, the present application provides a rapid visual detection method based on water-soluble perylene imide derivatives, and specifically, the present application provides a method for detecting picric acid, wherein the above-mentioned perylene imide derivative or the perylene imide derivative prepared by the above-mentioned preparation method is used as a probe.

[0018] Preferably, the concentration of the probe is 2 μmol / L.

[0019] Specifically, the specific detection method is as follows: the above-mentioned probe is used for visual detection of picric acid in 10 mmol / L HEPES buffer solution (pH = 7.0) with a concentration of 2 μmol / L, and the probe is quenched under the irradiation of an ultraviolet lamp, and the quenched fluorescence can be recognized by naked eyes. Photographs are taken, and the RGB values of the reagent, test paper or reagent kit are extracted by a method well known to those skilled in the art, and a standard curve for detection is established with the concentration of picric acid as the abscissa and G / B as the ordinate.

[0020] Compared with the prior art, the present application provides a rapid visual detection method based on water-soluble perylene imide derivatives, and the perylene imide derivative with the structure shown in formula (I) is used as a probe. The above-mentioned perylene imide derivative has good water solubility, can realize high-sensitivity and specific detection of picric acid, and can realize rapid visual quantitative detection. The detection method provided by the present application has high detection efficiency and sensitivity. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 Fluorescence emission spectrum (λ ex =440 nm, λ em =450-600 nm) of perylene imide derivative probe (2 μmol / L) after different concentrations of picric acid are added to HEPES buffer solution (10 mmol / L, pH = 7.0);

[0022] Figure 2 Fluorescence quenching efficiency curve (λ ex =440 nm, λ em =490 nm) of perylene imide derivative probe (2 μmol / L) after different concentrations of picric acid are added to HEPES buffer solution (10 mmol / L, pH = 7.0);

[0023] Figure 3 Relative fluorescence intensity (λ ex =440 nm, λ em =490 nm) of perylene imide derivative probe (2 μmol / L) and different substances (50 μmol / L) in HEPES buffer solution (10 mmol / L, pH = 7.0), and the inset is the fluorescence change under the irradiation of a 365 nm ultraviolet lamp,

[0024] 1 - Picric acid, 2 - Cl - ,3 - H2PO4 - ,4 - SO4 2- ,5 - NO 3- ,6 - CO3 2- ,7 - HCO3 - ,8 - Ca 2+ ,9 - K + ,10 - Na + ,11 - Mg 2+ ,12 - Pb 2+ ,13 - Cu 2+ ,14 - Al 3+ ,15 - Zn 2+ ,16 - Cd 2+ ,17 - Mn 2+ ,18 - Ag + ,19 - Nitropropionic acid (NPA), 20 - p-Nitrophenol (NP), 21 - Phenol (Phe), 22 - 2,4-Dinitrotoluene (DNT), 23 - 2,4-Dinitrophenol (DNP), 24 - Methylbenzene (MB), 25 - Nitrobenzene (NB), 26 - 2,4,6-Trinitrotoluene (TNT);

[0025] Figure 4 The photos of the solution of the perylene bisimide derivative under 365 nm UV light irradiation after adding different concentrations of picric acid (μmol / L);

[0026] Figure 5 The relationship between G / B and the concentration of picric acid of the perylene bisimide derivative probe (2 μmol / L) under 365 nm UV light irradiation after adding different concentrations of picric acid in HEPES buffer (10 mmol / L pH = 7.0);

[0027] Figure 6 The photos of the test paper of the perylene bisimide derivative probe under 365 nm UV light irradiation after adding different concentrations of picric acid (μmol / L);

[0028] Figure 7 The photos of the test paper of the perylene bisimide derivative probe under 365 nm UV light irradiation after adding different concentrations of picric acid (μmol / L); DETAILED DESCRIPTION

[0029] In order to further illustrate the present application, the rapid visual detection method based on water-soluble perylene bisimide derivatives provided by the present application is described in detail below in combination with examples.

[0030] Preparation of standby materials:

[0031] Preparation of buffer solution: 4-hydroxyethylpiperazineethanesulfonic acid solid was weighed and dissolved in distilled water to prepare 500 mL HEPES buffer solution with a concentration of 10 mmol / L. The pH value was adjusted to 7.0 by using 1 mol / L sodium hydroxide standard solution. The solution was stored in a 4°C refrigerator for standby use.

[0032] Preparation of probe mother liquor: the solid described in formula (I) was weighed and dissolved in distilled water to prepare a mother liquor with a concentration of 1 mmol / L. The mother liquor was divided into solutions with the same volume in vials for standby use. The prepared HEPES buffer solution (10 mmol / L, pH = 7.0) was used for dilution to a certain concentration for testing during spectral testing.

[0033] Preparation of test substances and interferents: picric acid was dissolved in distilled water to prepare a stock solution with a concentration of 1 mmol / L for standby use. Other interferents were dissolved in distilled water to prepare stock solutions with a concentration of 1 mmol / L. The solutions were stored in a 4°C refrigerator for standby use.

[0034] Preparation of test paper: 2 μmol / L perylene imide derivative solution was placed in a disposable plastic cuvette, and filter paper was processed into circles with the same diameter by using a 2.5 cm puncher. It was ensured that the different circular filter papers did not touch or overlap each other, and the circular filter papers were immersed in the perylene imide derivative solution for 10 seconds, and then taken out and naturally dried at room temperature to prepare test paper for subsequent visual detection.

[0035] Preparation of actual samples: the tap water and lake water obtained by sampling were boiled for half an hour, and after cooling to room temperature, they were filtered through a 0.22 μm PES filter membrane. The filtrate was used for actual sample detection. 0.1 g of soil sample was dissolved in 100 mL HEPES buffer solution (10 mmol / L, pH = 7.0), and then filtered through a 0.22 μm PES filter membrane. The filtrate was used for actual sample detection.

[0036] Example 1

[0037] Fluorescence spectroscopy test :

[0038] 2 μL of the probe mother liquor and 950 μL of 10 mmol / L HEPES buffer solution were mixed and added to a 1 mL sample cell. After uniform mixing, the fluorescence spectrum of the probe buffer solution was measured by using 440 nm fluorescence excitation and 450-600 nm fluorescence detection. The results are shown in Figure 1 The aforementioned perylene imide derivative has two emission peaks at 490 nm and 520 nm under 440 nm excitation. With the addition of picric acid, the emission peaks of the aforementioned perylene imide derivative gradually decrease.

[0039] The fluorescence intensity of the probe at a wavelength of 490 nm was recorded as I0. A picric acid solution of a certain concentration was added, and the fluorescence intensity at 490 nm was recorded as I. A detection standard curve was established with picric acid concentration on the x-axis and probe fluorescence quenching efficiency on the y-axis. The results are as follows: Figure 2 As shown (that is, Figure 2 This indicates the degree of fluorescence quenching of the aforementioned perylene imide derivative at 490 nm in HEPES (10 mmol / L, pH = 7.0) buffer with increasing picric acid concentration. QI = [(I0 - I) / I0] × 100%, λ ex =440nm). Based on the method for calculating the detection limit, the detection limit of perylene imide derivatives for picric acid is 9 nmol / L.

[0040] Example 2

[0041] Selective study:

[0042] Common interfering substances and structural analogs in the detection of picric acid were selected, including Cl. - H2PO4 - SO4 2- NO 3- CO3 2- HCO3 - Ca 2+ K + Na + Mg 2+ Pb 2+ Cu 2+ Al 3+ Zn 2+ Cd 2+ Mn 2+ Ag + The following substances were tested: nitropropionic acid (NPA), p-nitrophenol (NP), phenol (Phe), 2,4-dinitrotoluene (DNT), 2,4-dinitrophenol (DNP), toluene (MB), nitrobenzene (NB), and 2,4,6-trinitrotoluene (TNT). The concentration of the aforementioned perylene imide derivatives was 2 μmol / L, and the concentration of picric acid and all other interfering substances was 50 μmol / L. Fluorescence spectra were measured under the same conditions. The absorbance of the perylene imide derivatives at 490 nm before and after the addition of the interfering substances was compared, with I0 / I serving as a parameter to measure the influence of the aforementioned perylene imide derivatives on the analytes.

[0043] The results are as follows Figure 3 As shown (that is, Figure 3 The graph shows the relative absorbance values ​​of the aforementioned perylene imide derivatives interacting with picric acid and other interfering substances in HEPES (10 mmol / L, pH = 7.0) buffer.

[0044] As can be seen from the figure, the I0 / I of picric acid is about 5.6, which is 3.3 times of the strongest responding DNP among the interferents, while the I0 / I of all other substances remains at a low level (≤1.6), which is much higher than that of other compounds. This result indicates that the aforementioned perylene imide derivative has excellent selectivity for picric acid. Figure 3 The inset in FIG. 1 is a picture of the fluorescence change of the perylene imide derivative under 365 nm UV light irradiation before and after the addition of picric acid and other interferents. The perylene imide derivative initially presents bright fluorescence, and after the addition of picric acid, significant fluorescence quenching occurs, which can be observed by the naked eye. However, after the addition of other interferents, no obvious fluorescence quenching of the perylene imide derivative occurs.

[0045] The above results indicate that the perylene imide derivative has excellent selectivity for picric acid.

[0046] Example 3

[0047] Solution visualisation test :

[0048] The concentration of the aforementioned perylene imide derivative is 2 μmol / L, and different concentrations of picric acid are added.

[0049] Figure 4 FIG. 2 is a picture of the addition of different concentrations of picric acid under 365 nm UV light irradiation. As can be seen, with the increase of the concentration of picric acid, the fluorescence of the corresponding solution gradually changes from green to dark until complete quenching, and the visual detection limit of the solution is 10 μmol / L.

[0050] Example 4

[0051] The concentration of the aforementioned perylene imide derivative is 2 μmol / L, different concentrations of picric acid are added, and the RGB values are extracted. The picric acid concentration is taken as the horizontal coordinate, and the G / B is taken as the vertical coordinate to establish a detection standard curve, and the results are shown in FIG. 3 (i.e., the curve showing the change of the G / B value of the aforementioned perylene imide derivative with the concentration of picric acid in HEPES (10 mmol / L, pH = 7.0) buffer solution), and the lowest detection concentration is 1.05 μmol / L. Figure 5 Figure 5

[0052] Example 5

[0053] Test strip visualisation test :

[0054] The same volume of different concentrations of picric acid solution is added to the aforementioned perylene imide test paper. Figure 6 ​​The photos of test paper under 365 nm UV light after adding different concentrations of picric acid can be seen. When the concentration of picric acid is 0.1 μmol / L, the test paper shows significant fluorescence quenching. Therefore, 0.1 μmol / L is the visual detection limit of the test paper.

[0055] Example 6

[0056] In order to more intuitively observe the effect of the interaction between the aforementioned perylene imide derivative and picric acid and its interferents, the solution fluorescence was detected under 365 nm UV light. The solution fluorescence changes during the investigation of the selectivity of the aforementioned perylene imide derivative test paper to picric acid.

[0057] Picric acid and the aforementioned interfering substances, such as Figure 7 As shown, when the concentration of the interferent added to the test paper is 10 μL 100 μmol / L, the fluorescence of the test paper does not change, but when picric acid is added, the solution fluorescence is strongly quenched.

[0058] Example 7

[0059] Application to real samples :

[0060] In order to verify the feasibility of the detection method in actual samples, tap water, lake water and soil samples were selected for recovery rate determination.

[0061] The recovery rates of the tap water sample after adding 0.6 μmol / L and 1.0 μmol / L picric acid were 108.2% and 104.6% (RSD < 3%), respectively. The recovery rates of the lake water sample after adding 0.4 μmol / L, 1.4 μmol / L and 2.20 μmol / L picric acid were 102.5%, 100.7% and 95.5% (RSD < 3%), respectively. The recovery rates of the soil sample after adding 0.4 μmol / L, 1.4 μmol / L and 2.20 μmol / L picric acid were 107.5%, 94.0% and 98.0% (RSD < 6%), respectively. The results show that the method has good accuracy.

Claims

1. Use of perylene imide derivative represented by formula (I) in detecting picric acid; 2. A method of detecting picric acid, characterized by, Using perylene imide derivative represented by formula (I) as a probe; 3. A reagent, test paper or kit for detecting picric acid, characterized in that, The application relates to a method for detecting picric acid, comprising using perylene imide derivative represented by formula (I) as a probe; 4. Use according to claim 1, characterized in that, The fluorescence detection condition for detecting picric acid is that fluorescence excitation is at 440 nm, and fluorescence detection is at 450-600 nm.

5. The method of claim 2, wherein, The detection reaction system is as follows: 600-3000 muL of total system, 10 mmol / L of HEPES buffer solution with a pH value of 7.0, 1-4 mu mol / L of the probe, and the rest is distilled water.

6. The method of claim 2, wherein, The RGB value of the reagent, test paper or reagent kit photo is extracted, and quantitative detection of picric acid is carried out based on G / B.

7. The reagent, test strip, or kit of claim 3, wherein, Qualitative or semi-quantitative detection is carried out under a UV lamp.

8. The reagent, test strip or kit of claim 3, wherein, The RGB value of the reagent, test paper or reagent kit photo is extracted, and quantitative detection of picric acid is carried out based on G / B. The RGB value of the reagent, test paper or reagent kit photo is extracted, and quantitative detection of picric acid is carried out based on G / B.

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