阅读说明：本技术 一种检测二甲基亚砜中痕量水的荧光探针的合成与应用 (Synthesis and application of fluorescent probe for detecting trace water in dimethyl sulfoxide ) 是由 张光耀 喻琨 颜廷义 周子杰 刘倩 王希雁 曲丽君 于 2021-09-23 设计创作，主要内容包括：本发明属于化学分析检测技术领域,涉及一种检测二甲基亚砜中痕量水的荧光探针的合成与应用。将卟啉和锰离子通过简便的溶剂热法即可制备Mn-TCPP(BPDC)材料,该材料对水具有较强的荧光响应,对有机溶剂二甲基亚砜(DMSO)没有响应,对DMSO中的含水量具有较好的荧光线性范围响应。本发明荧光探针制备简单、方便,对水分的检测具有灵敏度高、线性范围大、稳定性和重复性好等优点。(The invention belongs to the technical field of chemical analysis and detection, and relates to synthesis and application of a fluorescent probe for detecting trace water in dimethyl sulfoxide. Porphyrin and manganese ions can be used for preparing the Mn-TCPP (BPDC) material by a simple solvothermal method, and the material has stronger fluorescence response to water, no response to an organic solvent dimethyl sulfoxide (DMSO) and better fluorescence linear range response to the water content in the DMSO. The fluorescent probe is simple and convenient to prepare, and has the advantages of high sensitivity, large linear range, good stability and repeatability and the like for detecting moisture.)

1. A synthetic method of a fluorescent probe Mn-TCPP (BPDC) for detecting trace water in dimethyl sulfoxide is characterized by comprising the following steps:

TCPP, manganese salt and BPDC are taken as raw materials to carry out solvent thermal reaction, thus obtaining the catalyst.

2. The method for synthesizing a fluorescent probe Mn-TCPP (BPDC) for detecting trace amount of water in dimethyl sulfoxide according to claim 1, wherein the manganese salt is manganese nitrate tetrahydrate.

3. The method for synthesizing the fluorescent probe Mn-TCPP (BPDC) for detecting trace water in dimethyl sulfoxide according to claim 1, wherein the specific conditions of the solvothermal method are as follows: reacting at 150-180 ℃ for 1-1.5 hours, preferably stirring at 150 ℃ for 1 hour.

4. The method for synthesizing a fluorescent probe Mn-TCPP (BPDC) for detecting trace amount of water in dimethyl sulfoxide according to claim 1, further comprising: cooling, solid-liquid separation, washing and drying.

5. The method for synthesizing the fluorescent probe Mn-TCPP (BPDC) for detecting trace water in dimethyl sulfoxide according to claim 1, wherein the mass ratio of TCPP to manganese salt to BPDC is 2-5: 4-8: 5-10, preferably, the mass ratio is 2: 4.2: 5.

6. the method for synthesizing the fluorescent probe Mn-TCPP (BPDC) for detecting trace water in dimethyl sulfoxide according to claim 1, wherein the solvothermal reaction is performed in an inert gas atmosphere, and preferably, the inert gas is nitrogen.

7. The method for synthesizing the fluorescent probe Mn-TCPP (BPDC) for detecting trace water in dimethyl sulfoxide according to claim 1, wherein the fluorescent probe Mn-TCPP (BPDC) is washed by ethanol for 3-4 times and dried in vacuum for 10-12 hours.

8. A fluorescent probe Mn-TCPP (BPDC) synthesized according to the method of any one of claims 1 to 7.

9. A method for detecting the content of trace water in an organic solvent rapidly is characterized by comprising the following steps:

preparing organic solvents with different water contents as standard solutions;

adding the fluorescent probe Mn-TCPP (BPDC) of claim 8 into the standard solution, uniformly mixing, and detecting a fluorescent response;

establishing a corresponding relation between the water content and the fluorescence intensity according to the measured fluorescence intensity;

adding the fluorescent probe Mn-TCPP (BPDC) of claim 8 into an organic solvent to be detected, uniformly mixing, detecting fluorescence response, and calculating the water content to obtain the fluorescent probe.

10. The method for detecting the content of trace water in the organic solvent according to claim 9, wherein the organic solvent is acetone, N-dimethylformamide, dimethyl sulfoxide, ethanol, isopropanol or methanol;

preferably, the concentration of Mn-TCPP (BPDC) is 2-3 mug/mL; most preferably, the concentration of Mn-TCPP (BPDC) is 2.5. mu.g/mL;

or, the excitation wavelength is 415nm, and the emission wavelength is 650 nm;

or the water volume content is 0.05-30% v/v.

Technical Field

The invention belongs to the technical field of chemical analysis and detection, and particularly relates to a preparation method and application of a porphyrin MOF fluorescent probe for detecting trace water in dimethyl sulfoxide (DMSO).

Background

The information in this background section is only for enhancement of understanding of the general background of the invention and is not necessarily to be construed as an admission or any form of suggestion that this information forms the prior art that is already known to a person of ordinary skill in the art.

Water is one of the most common impurities in organic solvents, seriously compromising laboratory chemistry and industrial manufacturing. Therefore, the development of a simple, fast and reliable sensor for detecting water in organic solvents is urgently needed. The traditional and widely used techniques for determining water content are karl fischer titration and gas chromatography. However, these methods have limitations including the need for specialized equipment, trained personnel, time consuming procedures, and the inability to monitor in real time on site. The fluorescence sensor has the characteristics of simple operation, quick response, high sensitivity, easy manufacture, capability of carrying out noninvasive in-situ detection and the like, and is considered as a potential substitute of the traditional analysis method.

In recent years, many fluorescent probes excited by water response have been reported. However, most probes are complex to synthesize, large in dosage, low in sensitivity, limited in detection range, and part of the probes are poor in stability, difficult to store and incapable of being recycled.

Disclosure of Invention

Aiming at the current detection situation of water in the organic solvent dimethyl sulfoxide, the invention aims to provide a synthesis and application research of a probe capable of rapidly detecting trace water in the organic solvent dimethyl sulfoxide.

In order to achieve the technical purpose, the invention adopts the following technical scheme:

in a first aspect of the present invention, a method for synthesizing a fluorescent probe Mn-tcpp (bpdc) for detecting trace amount of water in dimethyl sulfoxide is provided, which comprises:

TCPP, manganese salt and BPDC are taken as raw materials to carry out solvent thermal reaction, thus obtaining the catalyst.

The MOF material Mn-TCPP (BPDC) is synthesized by a solvothermal method, and the porphyrin TCPP in the MOF material generates fluorescence quenching effect due to electron transfer to metal ions (LMCT). The material can recognize and combine trace water molecules in organic solvent, and further recover fluorescence as a response signal. The technical method has the advantages of high detection speed, high sensitivity, simple operation, low cost and the like.

In a second aspect of the invention, there is provided a fluorescent probe Mn-TCPP (BPDC) synthesized by any of the above-described methods.

The synthesis of the porphyrin-based MOF only needs one step, the synthesis time is short, the raw materials are cheap and easy to obtain, and the dosage is very small. The porphyrin ligand in the material determines the fluorescence property of the material to be outstanding. The self fluorescence of the MOF probe formed by modification can be almost completely masked, and the fluorescence intensity is rapidly enhanced after the MOF probe reacts with water for several seconds, and the enhancement range is large. The material has the advantages of low detection limit (0.04%), high sensitivity, small dosage (0.25 mu g/mL) and no pollution.

In a third aspect of the present invention, there is provided a method for detecting the content of trace water in an organic solvent, comprising:

preparing organic solvents with different water contents as standard solutions;

adding the fluorescent probe Mn-TCPP (BPDC) into the standard solution, uniformly mixing, and detecting the fluorescent response;

establishing a corresponding relation between the water content and the fluorescence intensity according to the measured fluorescence intensity;

and adding the fluorescent probe Mn-TCPP (BPDC) into an organic solvent to be detected, uniformly mixing, detecting fluorescent response, and calculating the water content to obtain the fluorescent probe.

The invention has the beneficial effects that:

(1) compared with the prior art, the invention has the following remarkable advantages: the Mn-TCPP (BPDC) MOF composite material has the advantages of simple synthesis process, less time consumption and cheap and easily-obtained raw materials. The method is applied to the field of fluorescent probes, the property of the parent nucleus ligand is excellent, and a novel probe can be synthesized by derivation of the parent nucleus ligand. When the synthesized fluorescent probe MOF is used for detecting water, the fluorescence enhancement range is large, the sensitivity is high, the detection limit is low, the usage amount is small, and the like. In conclusion, the fluorescent probe is a tool which is low in cost, convenient, fast and sensitive, is suitable for detecting the concentration of trace water in the dimethyl sulfoxide organic solvent, and has wide application prospects in the field of chemical analysis and detection.

(2) The operation method is simple, low in cost, universal and easy for large-scale production.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.

FIG. 1 is a diagram of the mechanism of Mn-TCPP (BPDC) synthesis and sensing;

FIG. 2 is a photograph of Mn-TCPP (BPDC) prepared in example 1, wherein (1) is a (Scanning Electron Microscope) SEM image of Mn-TCPP (BPDC), (2) is an X-ray diffraction (XRD) spectrum of Mn-TCPP (BPDC), and (3) is an infrared spectrum of Mn-TCPP (BPDC);

FIG. 3 shows fluorescence intensity of Mn-TCPP (BPDC) prepared in example 1 in different solvents;

FIG. 4 is a graph of the fluorescence spectra (1) of Mn-TCPP (BPDC) prepared in example 1 in DMSO at various water contents, and a linear relationship between the fluorescence intensity and the water content (2);

FIG. 5 is a structural diagram of Mn-TCPP (BPDC).

Detailed Description

It is to be understood that the following detailed description is exemplary and is intended to provide further explanation of the invention as claimed. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

A preparation method of MOF material Mn-TCPP (BPDC) is shown in figure 5.

The details of the preparation method are as follows:

meso-tetra (4-carboxyphenyl) porphine (TCPP), manganese nitrate tetrahydrate Mn (NO)₃)₂·4H₂O and 4,4' -biphenyldicarboxylic acid (BPDC) were dissolved in N, N-Dimethylformamide (DMF) at room temperature, and the reaction mixture was dissolved inStirring for 1 hour at 150 ℃, cooling the reaction to room temperature, centrifuging, pouring out the mother liquor on the upper layer, washing with ethanol for 3 times, and vacuum-drying at 60 ℃.

The fluorescent probe of the invention has almost no fluorescence, and has strong fluorescence emission rapidly after water action, and the maximum emission wavelength is 650nm (lambda ex is 415 nm).

The fluorescent probe has good selectivity on water, the fluorescence is weak in acetone, DMF, DMSO, ethanol, isopropanol and methanol solutions, and the extremely strong fluorescence can be seen by naked eyes when the fluorescent probe is added into water under the same condition.

The fluorescent probe can be used for rapidly detecting the content of trace water in an organic solvent DMSO, and the method comprises the following steps:

adding Mn-TCPP (BPDC) into an organic solvent, adding quantitative water, shaking for 5min, and detecting a fluorescence response by using a fluorescence spectrometer.

Wherein the final concentration of Mn-TCPP (BPDC) is 2.5 mu g/mL, the excitation wavelength is 415nm, the emission wavelength is 650nm, and the volume content of water is 0.05-30% (v/v).

The fluorescent probes of the present invention exhibit high sensitivity for the detection of water. The fluorescence intensity of the probe solution increases with increasing water content. The fluorescence intensity reaches a peak at approximately 30% water content. In the range of 0 to 30 percent of water content, the fluorescence intensity of the probe solution has a good linear relation with the water content. The detection limit of the fluorescent probe in DMSO is 0.04%.

The stability research of the fluorescent probe disclosed by the invention shows that the detection of the probe on the water content is not influenced after the material is stored for 150 days.

The present invention is described in further detail below with reference to specific examples, which are intended to be illustrative of the invention and not limiting.

Example 1

Referring to FIG. 1, the preparation and sensing process of Mn-TCPP (BPDC) of the present invention is as follows:

(1) after 2mg of TCPP, 4.2mg of manganese nitrate tetrahydrate and 5mg of BPDC were dissolved in 12mL of DMF, the solution was added to a Schlenk tube under nitrogen protection, and stirred and refluxed at 150 ℃ for one hour;

(2) the reaction solution cooled to room temperature is centrifuged (rotation speed 7000r/min), washed with ethanol for 3 times, and dried in vacuum for 10h to obtain Mn-TCPP (BPDC).

(3) Ultrasonically dispersing the Mn-TCPP (BPDC) probe obtained in the step (2) in ethanol (1mg/mL) for later use. And (3) adding 2mL of the solution to be detected into 5 mu L of the probe solution, shaking for 5min, and measuring the fluorescence intensity.

(4) After the probe is added into DMSO with low water content, weak fluorescence can be seen under a 365nm ultraviolet lamp, because the fluorescence is weakly recovered due to ligand exchange between water molecules in the DMSO and BPDC and binding to a metal node. When the water content is higher, the water molecules break the metal nodes, so that porphyrin is released, and the fluorescence is enhanced violently.

Example 2

Appearance and structure characterization of Mn-TCPP (BPDC) material

The MOF probe Mn-tcpp (bpdc) prepared in example 1 was morphologically characterized by scanning electron microscopy, as shown in (1) of fig. 2, and it can be seen from (1) of fig. 2 that the MOF material was in the shape of regular square biscuit and was uniform in morphology. The XRD pattern shows that Mn-TCPP (BPDC) has a uniform crystal structure. Molecular binding patterns of probes were determined using infrared spectroscopy, including 1580cm^-1Turbine structure representing metal node, 1009cm^-1Formation of metalloporphyrin and 965cm^-1The presence of hollow porphyrin was confirmed, and the microstructure of the material Mn-TCPP (BPDC) was confirmed.

Example 3

Mn-TCPP (BPDC) material selectivity and application

The dispersed MOF material Mn-TCPP (BPDC) prepared in example 1 is added with 2mL of water, DMSO, methanol, ethanol, isopropanol, acetone and DMF respectively, vibrated for 5min at normal temperature, transferred to a quartz cuvette, and the fluorescence intensity at 650nm is measured at the excitation wavelength of 415 nm. The test solution was irradiated with a 365nm ultraviolet lamp and observed for fluorescence. The detection result is shown in (figure 3), the photo of the fluorescence intensity at 650nm and the photo under 365nm ultraviolet lamp shows that the material has no fluorescence response in the anhydrous organic solvent and only emits light in water, thus having good selectivity.

Preparing a DMSO solution with the water content of 0-40%, adding the dispersed MOF material Mn-TCPP (BPDC) into 2mL of the prepared solution, oscillating for 5min at normal temperature, transferring to a quartz cuvette, and measuring the fluorescence spectrum of 600-800 nm under the excitation wavelength of 415 nm. As shown in fig. 4 (1), the fluorescence intensity of the solution increased with the increase in the water content of the test solution, and thus a good linear relationship between the water content and the fluorescence intensity at 650nm was obtained (fig. 4 (2) and (3)), where the linear equation is y 550x +143(C < 10%), y 23979 x-249178 (C > 10%), the linear range is 0.05% to 30%, and the minimum detection limit is 0.04%. The MOF material Mn-TCPP (BPDC) has low lower limit of fluorescence detection on water, wide detection range and good application value.

It should be noted that the above-mentioned embodiments are only preferred embodiments of the present invention, and the present invention is not limited thereto, and although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications and equivalents can be made in the technical solutions described in the foregoing embodiments, or equivalents thereof. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.