A dual-emission fluorescent probe Cl, N-GQDs@EuBTC, a preparation method and application thereof
By preparing dual-emission fluorescent probes Cl,N-GQDs@EuBTC, the problems of high detection limit and limited detection range in existing technologies were solved, and high-sensitivity and rapid detection of water content in organic solvents was achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CCS (SHANGHAI) FUNCTIONAL FILMS IND CO LTD
- Filing Date
- 2023-09-26
- Publication Date
- 2026-06-26
AI Technical Summary
Existing technologies for detecting water content in organic solvents suffer from problems such as high detection limits, complex methods, environmental sensitivity, and limited detection range.
A dual-emission fluorescent probe Cl,N-GQDs@EuBTC was prepared using a one-pot solvothermal method. The composite material of Cl,N-GQDs and EuBTC was used as a ratiometric fluorescent sensor to achieve rapid detection of water content in organic solvents by recording the fluorescence intensity ratio.
It achieves highly sensitive detection of water content in organic solvents, with a detection limit as low as 0.018 v%, applicable to a variety of solvents, with a wide detection range, and the method is simple and rapid.
Smart Images
Figure CN117304921B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of nanomaterial sensing technology, specifically to a dual-emission fluorescent probe Cl,N-GQDs@EuBTC, its preparation method, and its applications. Background Technology
[0002] Many organic reactions require strictly anhydrous conditions, and even trace amounts of water can limit reaction rates. However, water is one of the most common foreign substances in organic solvents. Furthermore, controlling water content or relative humidity is crucial in areas such as grain and wood storage and preservation. Therefore, quantitative detection of water is essential in fields such as fine chemicals, food inspection, pharmaceutical manufacturing, and laboratory chemistry.
[0003] Currently, methods for detecting water content include Karl Fischer titration, gas chromatography, and electrochemical methods. Among these, Karl Fischer titration is the most widely used, but these methods have certain limitations due to the requirements for specialized instruments and operators.
[0004] Patent CN115043855A discloses a method for detecting water content in heavy water using fluorescent organic small molecules. The method includes the following steps: Based on a thiazothiazolium structure, a fluorescent organic small molecule probe is obtained by chemically derivatizing it with 3,4-methylenedioxybenzyl chloride or 5-(4-bromophenyl)furfural. Then, a series of 10 μM probe heavy water solutions with different light water contents are prepared and placed in a fluorescence spectrophotometer for fluorescence detection. The excitation wavelength is 400 nm, and both the excitation and emission bandwidths are 5 nm. The fluorescence emission spectrum in the range of 400-650 nm is scanned and recorded. In this method, the fluorescent organic small molecule exhibits single-emission fluorescence. This single-response sensing method is susceptible to interference from the external environment, such as instrument stability and light source intensity, thus affecting the reliability of the sensing. Furthermore, the detection limit of this method is 0.174%, which is relatively high and limits its practical application.
[0005] Patent CN116462695A discloses a method for preparing a rhodamine B Schiff base aluminum complex and its application in detecting trace amounts of water in alcohol solvents. The rhodamine B Schiff base aluminum complex decomposes upon reaction with water, causing the lactam ring of the rhodamine B structure to close again, forming a free rhodamine B Schiff base. This affects the UV absorption and fluorescence intensity, thus enabling the detection of trace amounts of water in alcohol solvents. However, this fluorescence sensor can only be used to detect water content in alcohol solvents, and the fluorescence intensity at 596 nm shows a linear correlation with water content only when the water content in ethanol solvent is in the range of 0% to 0.7v%, limiting its detection range.
[0006] Therefore, it is of great significance to develop a simple, rapid and accurate method for determining the water content in organic solvents. Summary of the Invention
[0007] The purpose of this invention is to overcome the shortcomings of the aforementioned background technology and provide a dual-emission fluorescent probe Cl,N-GQDs@EuBTC, its preparation method, and its applications. This invention prepares a dual-emission Cl,N-GQDs@EuBTC nanocomposite material using yellow-emitting Cl,N-GQDs and red-emitting EuBTC as raw materials via a one-pot solvothermal method. This material exhibits good sensitivity to water, and Cl,N-GQDs@EuBTC can be used as a ratiometric fluorescent sensor for the rapid detection of trace amounts of water in organic solvents.
[0008] To achieve the objectives of this invention, the preparation method of the dual-emission fluorescent probe Cl,N-GQDs@EuBTC includes the following steps:
[0009] (1) Add julonidine and hexadecylpyridine chloride to a mixture of acetic acid and anhydrous ethanol, and then sonicate to obtain a mixture;
[0010] (2) The mixture obtained in step (1) was reacted at 195-225℃ for 8-20h, and after cooling, a brown Cl,N-GQDs suspension was obtained.
[0011] (3) The suspension obtained in step (2) was concentrated and purified by silica gel column chromatography to finally obtain black Cl,N-GQDs solid. The Cl,N-GQDs solid was dissolved in ethanol to obtain Cl,N-GQDs mother liquor.
[0012] (4) Europium nitrate hexahydrate and pyromellitic acid were added to a mixed solution of DMF and anhydrous ethanol, and then Cl,N-GQDs mother liquor was added for ultrasonic treatment. The resulting mixture was reacted at 110-130℃ for 35-60h. After cooling to room temperature, it was washed by centrifugation with DMF and anhydrous ethanol respectively, and then vacuum dried to obtain the final product.
[0013] Furthermore, in some embodiments of the present invention, the mass-volume ratio of julonidine, hexadecylpyridine chloride, acetic acid and anhydrous ethanol in step (1) is 0.4-0.6g: 0.08-0.12g: 7-13mL: 40-60mL.
[0014] Furthermore, in some embodiments of the present invention, the mixture obtained in step (1) in step (2) is reacted at 203-218°C for 10-18 hours.
[0015] Furthermore, in some embodiments of the present invention, the concentration of the Cl,N-GQDs mother liquor is 0.08-0.12 mg / mL.
[0016] Furthermore, in some embodiments of the present invention, the mass-to-volume ratio of europium nitrate hexahydrate, pyromellitic acid, DMF and anhydrous ethanol in step (4) is 0.08-0.12 mmol: 0.08-0.12 mmol: 15-25 mL: 3-7 mL.
[0017] Furthermore, in some embodiments of the present invention, the washing in step (4) is performed by centrifugation using DMF and anhydrous ethanol, respectively.
[0018] Furthermore, in some embodiments of the present invention, the vacuum drying in step (4) is performed at 50-70°C for 6-18 hours.
[0019] On the other hand, the present invention also provides a dual-emission fluorescent probe Cl,N-GQDs@EuBTC, which is prepared by the aforementioned method.
[0020] In another aspect, the present invention also provides an application of the aforementioned dual-emission fluorescent probe Cl,N-GQDs@EuBTC, wherein the application is to use the dual-emission fluorescent probe Cl,N-GQDs@EuBTC for the detection of water content in organic solvents.
[0021] Furthermore, in some embodiments of the present invention, the method for detecting water content in organic solvents using the dual-emission fluorescent probe Cl,N-GQDs@EuBTC is as follows:
[0022] (1) Dissolve the fluorescent probe Cl,N-GQDs@EuBTC in an organic solvent to obtain the detection stock solution;
[0023] (2) Add the test mother liquor obtained in step (1) to organic solvents with different water contents, mix them evenly, record their fluorescence spectra, and then obtain the standard working curve of fluorescence intensity ratio and water content by linear fitting.
[0024] (3) Add the detection mother liquor obtained in step (1) to the sample to be tested, stir evenly and record the fluorescence spectrum. According to the standard working curve, obtain the water content in the sample to be tested.
[0025] Furthermore, in some embodiments of the present invention, the concentration of the detection mother liquor is 0.8-1.2 mg / ml.
[0026] Furthermore, in some embodiments of the present invention, the organic solvent is anhydrous ethanol or tetrahydrofuran.
[0027] Furthermore, in some embodiments of the present invention, the luminescent Cl,N-GQDs@EuBTC is first excited by an ultraviolet lamp source, exhibiting obvious red and yellow fluorescence. After the sample to be tested is added, the intensity of the red fluorescence of Cl,N-GQDs@EuBTC decreases, while the intensity of the yellow fluorescence increases.
[0028] Furthermore, in some embodiments of the present invention, the water content in the sample to be tested is 0-5% v%.
[0029] Furthermore, in step (3), the volume ratio of the mother liquor to the sample to be tested is 0.8-1.2:2.5-3.5.
[0030] Compared with the prior art, the advantages of the present invention are as follows:
[0031] (1) This invention uses Cl,N-GQDs and EuBTC precursor as raw materials to obtain a dual-emission fluorescent probe material with good fluorescence detection performance, especially high sensitivity to water molecules. It can be well used to detect the water content in ethanol and has high sensitivity. The detection limit of the detection method can be as low as 0.018v.
[0032] (2) The fluorescent probe prepared by the present invention can be used to detect the water content in tetrahydrofuran, with a detection limit of 0.04 v%, and has broad application prospects and high practical application value.
[0033] (3) The fluorescent probe provided by the present invention has excellent fluorescence emission ability. It exhibits excellent sensitivity and accuracy when applied to the detection of water content in protic solvents and non-protic solvents. Moreover, the detection limit is lower than that of the prior art, and it has high practical application value. Attached Figure Description
[0034] Figure 1 This is a schematic diagram of the synthesis of the dual-emission fluorescent probe Cl,N-GQDs@EuBTC in Example 1 and its application in the detection of water content in organic solvents;
[0035] Figure 2 This is the fluorescence spectrum of fluorescent Cl,N-GQDs@EuBTC for ethanol with different water contents in Example 2 of the present invention;
[0036] Figure 3 This is a standard working curve of fluorescence intensity ratio versus water content in Example 2 of the present invention;
[0037] Figure 4 These are actual images of standard sample solutions and blank sample solutions of various concentrations in Example 2 of this invention under ultraviolet light and fluorescent light irradiation;
[0038] Figure 5This is the fluorescence spectrum of fluorescent Cl,N-GQDs@EuBTC against tetrahydrofuran with different water contents in Example 3 of the present invention;
[0039] Figure 6 This is a standard working curve of fluorescence intensity ratio versus water content in Example 3 of the present invention. Detailed Implementation
[0040] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. It should be understood that the following description is merely illustrative and not intended to limit the invention.
[0041] The terms “comprising,” “including,” “having,” “containing,” or any other variations thereof, as used herein, are intended to cover a non-exclusive inclusion. For example, a composition, step, method, article, or apparatus that includes the listed elements is not necessarily limited to those elements, but may include other elements not expressly listed or elements inherent to such composition, step, method, article, or apparatus.
[0042] The conjunction "composed of..." excludes any unspecified elements, steps, or components. If used in a claim, this phrase makes the claim closed, excluding materials other than those described, except for associated conventional impurities. When the phrase "composed of..." appears in a clause of the body of a claim rather than immediately following it, it limits only the elements described in that clause; other elements are not excluded from the claim as a whole.
[0043] When a quantity, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pair of any upper or preferred value with any lower or preferred value, regardless of whether the range is disclosed individually. For example, when the range “1 to 5” is disclosed, the described range should be interpreted as including the ranges “1 to 4”, “1 to 3”, “1 to 2”, “1 to 2 and 4 to 5”, “1 to 3 and 5”, etc. When numerical ranges are described herein, unless otherwise stated, the range is intended to include its endpoints and all integers and fractions within that range.
[0044] The singular form includes the plural objects of discussion unless the context clearly indicates otherwise. "Optional" or "any one" means that the matter or event described thereafter may or may not occur, and the description includes both the possibility that the event occurs and the possibility that the event does not occur.
[0045] Approximate terms used in the specification and claims to modify quantities indicate that the invention is not limited to that specific quantity, but also includes acceptable modifications close to that quantity that do not alter the relevant essential function. Correspondingly, the use of "about," "approximately," etc., to modify a numerical value means that the invention is not limited to that precise value. In some instances, approximate terms may correspond to the precision of the instrument used to measure the value. In this application's specification and claims, scope definitions can be combined and / or interchanged, unless otherwise stated, these scopes include all subscopes contained therein.
[0046] The indefinite articles “a” and “an” preceding an element or component of this invention do not impose any limitation on the quantity (i.e., number of times) of the element or component. Therefore, “an” or “a” should be interpreted as including one or at least one, and the singular form of an element or component also includes the plural form, unless the quantity clearly refers only to the singular form.
[0047] Furthermore, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., described below refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms are not necessarily directed at the same embodiment or example. Moreover, the technical features involved in the various embodiments of the present invention can be combined with each other as long as they do not conflict with each other.
[0048] Example 1
[0049] The preparation steps of the dual-emission fluorescent probe are as follows:
[0050] Julonidine (0.5 g) and hexadecylpyridine chloride (0.1 g) were added to a mixture of acetic acid (10 mL) and anhydrous ethanol (50 mL), followed by sonication for 30 min. The mixture was then transferred to a high-pressure reactor and reacted at 210 °C for 14 h. After cooling, a brown Cl,N-GQDs suspension was obtained. The suspension was concentrated and purified by silica gel column chromatography to finally obtain a black Cl,N-GQDs solid. An appropriate amount of Cl,N-GQDs was dissolved in ethanol to obtain a Cl,N-GQDs mother liquor (0.1 mg / mL). -1 ); add 500μL Cl,N-GQDs (0.1mg mL -1Europium nitrate hexahydrate (1 mmol) and trimesic acid (1 mmol) were added to a mixed solution of DMF (20 mL) and anhydrous ethanol (5 mL), and sonicated for 30 min. The mixture was then transferred to a hydrothermal reactor and reacted at 120 °C for 48 h. After cooling to room temperature, the mixture was washed twice by centrifugation with DMF and anhydrous ethanol, respectively, and dried in a vacuum oven at 60 °C for 12 h to obtain the final product.
[0051] Example 2
[0052] A method for using a dual-emission fluorescent probe, specifically for detecting water content in ethanol, comprises the following steps:
[0053] 10 mg of Cl,N-GQDs@EuBTC powder obtained in Example 1 was added to 10 mL of anhydrous ethanol and sonicated for 10 min to obtain a Cl,N-GQDs@EuBTC suspension. 0.5 mL of the suspension was transferred to a cuvette under stirring, and different volumes of water were added using a pipette (as shown in Table 1). The solution was then diluted with anhydrous ethanol to a total volume of 2 mL, ensuring the water volume ratio was between 0% and 3%. The fluorescence emission spectrum of the dual-emission fluorescent probe in the 500-700 nm range (excitation wavelength 470 nm) was tested, and a linear relationship curve was established between the fluorescence intensity ratio of Cl,N-GQDs and EuBTC and different water contents.
[0054] Table 1
[0055]
[0056]
[0057] Example 3
[0058] A method for using a dual-emission fluorescent probe, specifically for detecting water content in tetrahydrofuran, comprises the following steps:
[0059] 10 mg of Cl,N-GQDs@EuBTC powder obtained in Example 1 was added to 10 mL of tetrahydrofuran and sonicated for 10 min to obtain a Cl,N-GQDs@EuBTC suspension. 0.5 mL of the suspension was transferred to a cuvette under stirring. Different volumes of water were added using a pipette (as shown in Table 2), and the solution was diluted with tetrahydrofuran to a total volume of 2 mL, so that the water volume ratio was 0-5 v%. The fluorescence emission spectrum of the dual-emission fluorescent probe in the range of 500-700 nm (excitation wavelength 470 nm) was tested. A linear relationship curve was established between the fluorescence intensity ratio of Cl,N-GQDs and EuBTC and different water contents.
[0060] Table 2
[0061] 0v％ 0.1v％ 0.5v％ 1v％ 2v％ 3v％ 4v％ Tetrahydrofuran / ml 1.5 1.498 1.49 1.48 1.46 1.44 1.42 water / ml 0 0.002 0.01 0.02 0.04 0.06 0.08 Mother liquor / ml 0.5 0.5 0.5 0.5 0.5 0.5 0.5
[0062] like Figure 1 As shown, the fluorescent probe Cl,N-GQDs@EuBTC was first excited by an ultraviolet light source, exhibiting distinct red and yellow fluorescence. The addition of a trace amount of water caused a change in the fluorescence of the probe.
[0063] like Figure 2 As shown, with the increase of water content in ethanol, the yellow fluorescence of the fluorescent probe Cl,N-GQDs@EuBTC at 540 nm is enhanced, and the red fluorescence at 616 nm is quenched.
[0064] like Figure 3 As shown, within the ethanol-water content range of 0-5 v%, the fluorescence intensity ratio of Cl,N-GQDs@EuBTC is (I 540 / I 616 A good linear relationship was observed between the concentration of 0-5 v% ethanol and the water content, and a good standard working curve was obtained by fitting: y = 0.25937x + 0.65016, R0. 2 =0.98554.
[0065] like Figure 4 As shown, under ultraviolet light (365nm) irradiation, as the water content in ethanol increases, the fluorescence of the Cl,N-GQDs@EuBTC solution undergoes a significant color change, gradually changing from rose red to the corresponding orange, which can be directly identified by the naked eye.
[0066] like Figure 5 As shown, with the increase of water content in tetrahydrofuran, the yellow fluorescence of the fluorescent probe Cl,N-GQDs@EuBTC at 540 nm is enhanced, and the red fluorescence at 616 nm is quenched.
[0067] like Figure 6 As shown, within the tetrahydrofuran water content range of 0-4v%, the fluorescence intensity ratio of Cl,N-GQDs@EuBTC was (I 540 / I 616 The reaction exhibits a good linear relationship with the 0–3 v% ethanol water content, and a good standard working curve is obtained through fitting: y = 0.09527x + 0.69808, R0. 2 =0.99722.
[0068] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A method for preparing a dual-emission fluorescent probe Cl,N-GQDs@EuBTC, characterized in that, The preparation method of the dual-emission fluorescent probe Cl,N-GQDs@EuBTC includes the following steps: (1) Julonidine and hexadecylpyridine chloride were added to a mixture of acetic acid and anhydrous ethanol, and then ultrasonically treated to obtain a mixture; (2) The mixture obtained in step (1) was reacted at 195-225℃ for 8-20 h, and after cooling, a brown Cl,N-GQDs suspension was obtained; (3) After the suspension obtained in step (2) is concentrated, it is separated and purified by silica gel column chromatography to finally obtain black Cl,N-GQDs solid. The Cl,N-GQDs solid is dissolved in ethanol to obtain Cl,N-GQDs mother liquor. (4) Europium nitrate hexahydrate and pyromellitic acid were added to a mixed solution of DMF and anhydrous ethanol, and then Cl,N-GQDs mother liquor was added for ultrasonic treatment. The resulting mixture was reacted at 110-130℃ for 35-60 h. After cooling to room temperature, it was centrifuged and washed with DMF and anhydrous ethanol respectively, and then vacuum dried to obtain the final product.
2. The method for preparing the dual-emission fluorescent probe Cl,N-GQDs@EuBTC according to claim 1, characterized in that, In step (1), the mass-to-volume ratio of julonidine, hexadecylpyridine chloride, acetic acid and anhydrous ethanol is 0.4-0.6 g: 0.08-0.12 g: 7-13 mL: 40-60 mL.
3. The method for preparing the dual-emission fluorescent probe Cl,N-GQDs@EuBTC according to claim 1, characterized in that, In step (2), the mixture obtained in step (1) is reacted at 203-218℃ for 10-18 h.
4. The method for preparing the dual-emission fluorescent probe Cl,N-GQDs@EuBTC according to claim 1, characterized in that, The concentration of the Cl,N-GQDs mother liquor was 0.08-0.12 mg / mL.
5. The method for preparing the dual-emission fluorescent probe Cl,N-GQDs@EuBTC according to claim 1, characterized in that, In step (4), the mass-to-volume ratio of europium nitrate hexahydrate, pyromellitic acid, DMF and anhydrous ethanol is 0.08-0.12 mmol: 0.08-0.12 mmol: 15-25 mL: 3-7 mL.
6. The method for preparing the dual-emission fluorescent probe Cl,N-GQDs@EuBTC according to claim 1, characterized in that, In step (4), the washing process involves centrifugation with DMF and anhydrous ethanol, respectively.
7. The method for preparing the dual-emission fluorescent probe Cl,N-GQDs@EuBTC according to claim 1, characterized in that, In step (4), vacuum drying is performed at 50-70℃ for 6-18 hours.
8. A dual-emission fluorescent probe Cl,N-GQDs@EuBTC, characterized in that, The dual-emission fluorescent probe Cl,N-GQDs@EuBTC is prepared using the method described in any one of claims 1-7.
9. The application of the dual-emission fluorescent probe Cl,N-GQDs@EuBTC according to claim 8, characterized in that, The application involves using the dual-emission fluorescent probe Cl,N-GQDs@EuBTC for the detection of water content in organic solvents.
10. The application of the dual-emission fluorescent probe Cl,N-GQDs@EuBTC according to claim 9, characterized in that, The method for detecting water content in organic solvents using the dual-emission fluorescent probe Cl,N-GQDs@EuBTC is as follows: (1) Dissolve the fluorescent probe Cl,N-GQDs@EuBTC in an organic solvent to obtain the detection stock solution; (2) Add the test mother liquor obtained in step (1) to organic solvents with different water contents, mix them evenly, record their fluorescence spectra, and then obtain the standard working curve of fluorescence intensity ratio and water content by linear fitting. (3) Add the test mother liquor obtained in step (1) to the sample to be tested, stir evenly and record the fluorescence spectrum. According to the standard working curve, obtain the water content in the sample to be tested.
11. The application of the dual-emission fluorescent probe Cl,N-GQDs@EuBTC according to claim 10, characterized in that, The concentration of the test mother solution is 0.8-1.2 mg / ml.
12. The application of the dual-emission fluorescent probe Cl,N-GQDs@EuBTC according to claim 10, characterized in that, The organic solvent is anhydrous ethanol or tetrahydrofuran.
13. The application of the dual-emission fluorescent probe Cl,N-GQDs@EuBTC according to claim 10, characterized in that, The water content in the sample to be tested is 0-5%.
14. The application of the dual-emission fluorescent probe Cl,N-GQDs@EuBTC according to claim 10, characterized in that, In step (3), the volume ratio of the mother liquor to the sample to be tested is 0.8-1.2:2.5-3.5.