A fluorescent probe for detecting metal palladium, a fluorescent nanofiber membrane, and a preparation method and application thereof

Abstract

The present invention belongs to the technical field of molecular probes and nanotextile materials, and specifically relates to a fluorescent probe for detecting metallic palladium, a fluorescent nanofiber membrane, and a preparation method and application thereof. The fluorescent probe for detecting metallic palladium provided by the present invention has benzopyran as a fluorescent parent nucleus and allyl as a recognition site, has a novel structure, and can realize effective detection of palladium element in the environment. Furthermore, the fluorescent nanofiber membrane for detecting metallic palladium provided by the present invention effectively combines electrospinning technology with a fluorescent probe, and utilizes the fluorescent opening performance after the fluorescent probe reacts with metallic palladium to realize rapid detection of palladium element. In addition, the fluorescent nanofiber membrane has the characteristics of simple preparation, low cost, and reusability, and can provide a powerful tool for realizing rapid and simple detection of palladium-containing elemental pollutants in the environment, and has extremely broad application prospects in the field of metallic palladium detection.

Description

Technical Field

[0001] The invention belongs to the technical field of molecular probes and nano textile materials, and specifically relates to a fluorescent probe for detecting metal palladium, a fluorescent nanofiber membrane, and a preparation method and application thereof. Background Art

[0002] Palladium is a platinum group metal with unique catalytic properties. It has been widely used in organic synthesis, pharmaceutical synthesis, aerospace and other fields. For example, in catalytic converters that treat automobile exhaust, the palladium content can reach more than 96%. However, palladium is also a common environmental pollutant. It will be gradually released into water bodies during the production and application process, spread in the soil, atmosphere and water bodies, and accumulate through the food chain, causing adverse effects on the ecological environment. In addition, palladium will also combine with biological macromolecules such as DNA, proteins, amino acids, and vitamins in the human body, thereby increasing human health risks, including potential respiratory problems, allergic reactions, and the accumulation of toxins of toxic palladium compounds in the body. Therefore, effective monitoring of palladium content is an important way to timely detect and prevent palladium pollution.

[0003] For the detection of palladium metal, the commonly used methods are atomic adsorption spectroscopy (AAS) and inductively coupled plasma mass spectrometry (ICP-MS), both of which have the advantage of high sensitivity. However, the above methods usually require sophisticated instruments when detecting palladium content, and also have quite cumbersome sample preparation procedures, and require experienced instrument operators to operate, which is not suitable for large-scale samples or on-site detection applications. Compared with the above two methods, the fluorescence method has the advantages of convenience, easy operation, rapidity and efficiency, high detection sensitivity and visualization. However, most of the current probes are for the detection of palladium ions, and there are relatively few types of fluorescent probes that can be used for the detection of palladium elements, which cannot meet the detection needs of palladium-containing elemental pollutants.

[0004] In addition, electrospinning is a fiber generation technology based on electrostatics. By combining electrospinning with fluorescent probes, it is beneficial to the fabrication of nanofiber sensors. These sensors have significant characteristics such as portability, stability, durability, high sensitivity and rapid response, and can be used to detect metal ions, small molecules and gases, which are very suitable for various application scenarios.

[0005] At present, there is still a lack of feasible solutions in the prior art that combine electrospinning technology and fluorescent probe technology for palladium metal detection. How to provide a new fluorescent probe for palladium metal detection and effectively combine the fluorescent probe with electrospinning fibers to achieve rapid and simple detection of palladium in the environment has become a technical problem to be solved by the present invention. Summary of the invention

[0006] In view of the above problems, one of the objectives of the present invention is to provide a fluorescent probe for detecting metallic palladium, which uses benzopyran as a fluorescent parent nucleus and allyl as a recognition site, and can achieve effective detection of metallic palladium in the environment.

[0007] The second object of the present invention is to provide a method for preparing the fluorescent probe for detecting metal palladium.

[0008] The third object of the present invention is to provide the application of the above-mentioned fluorescent probe for detecting metal palladium.

[0009] The fourth object of the present invention is to provide a fluorescent nanofiber membrane for detecting metallic palladium, which can provide a powerful tool for the rapid and convenient detection of palladium in the environment.

[0010] The fifth object of the present invention is to provide the application of the above-mentioned fluorescent nanofiber membrane for detecting metal palladium.

[0011] To achieve the above object, the technical solution adopted by the present invention is:

[0012] A fluorescent probe for detecting metallic palladium is a compound having a structure shown in formula (I):

[0013] Formula (I).

[0014] The preparation method of the fluorescent probe for detecting metal palladium comprises the following steps:

[0015] The compound represented by formula (II) is reacted with allyl chloroformate in a solvent, and then purified to obtain a fluorescent probe for detecting metal palladium;

[0016] Formula (II).

[0017] Preferably, the reaction molar ratio of the compound represented by formula (II) to allyl chloroformate is 1:(1.8-2.2), more preferably 1:2.

[0018] Preferably, the reaction temperature is 15-30° C. and the reaction time is 4-8 min.

[0019] Preferably, the solvent is triethylamine and anhydrous dichloromethane; and the purification adopts column chromatography separation technology.

[0020] The above-mentioned application of the fluorescent probe for detecting metallic palladium is used as a molecular probe in detecting single substance palladium.

[0021] A fluorescent nanofiber membrane for detecting metal palladium is prepared by a method comprising the following steps:

[0022] The fluorescent probe for detecting metal palladium is mixed evenly with a high molecular polymer solution to obtain a spinning solution; the spinning solution is subjected to an electrostatic spinning process to obtain a fluorescent nanofiber membrane for detecting metal palladium;

[0023] Wherein, the polymer solution uses polyvinyl butyral as the polymer; the fluorescent probe for detecting metal palladium is a compound having a structure shown in formula (I):

[0024] Formula (I).

[0025] In the present invention, polyvinyl butyral is a condensate of polyvinyl alcohol and butyraldehyde, which has excellent softness and flexibility and is suitable for loading of fluorescent probes and subsequent reaction with palladium element.

[0026] Preferably, the ratio of the fluorescent probe for detecting metal palladium to the high molecular polymer solution is 1 mg: (0.8-1.2) mL, more preferably 1 mg: 1 mL.

[0027] More preferably, the uniform mixing is stirring mixing; the stirring mixing time is 8 to 16 hours.

[0028] Preferably, the mass concentration of the high molecular polymer solution is 7% to 9%, more preferably 8%.

[0029] Preferably, the process conditions of the electrospinning treatment are: the spinning voltage is 10 kV~20 kV, and the spinning solution flow rate is 2~3 mL / h.

[0030] The above-mentioned application of the fluorescent nanofiber membrane for detecting metallic palladium is used in the detection of single substance palladium.

[0031] The technical solution of the present invention has the following advantages and beneficial effects:

[0032] (1) The fluorescent probe for detecting metallic palladium provided by the present invention has benzopyran as the fluorescent parent nucleus and allyl as the recognition site, and has a novel structure. At the same time, the present invention has confirmed through the selective test of solvent and metal ion that the fluorescent probe has a good sensitivity to palladium (Pd 0 ) have a single selective recognition effect. Therefore, this probe can effectively realize Pd 0 The detection object can be a Pd 0 Common water bodies such as tap water, river water, industrial wastewater, etc.

[0033] Meanwhile, the fluorescent probe is prepared by subjecting the intermediate of formula II to substitution reaction with allyl chloroformate. The raw materials for preparing the probe are easily available, the synthesis process is simple, the operation is simple, and it is suitable for mass preparation and industrial production.

[0034] (2) The fluorescent nanofiber membrane for detecting metal palladium provided by the present invention is a nanofiber composite membrane with good performance successfully prepared by using fluorescent probes and high molecular polymers. The present invention effectively combines electrospinning technology with fluorescent probes. The fluorescent nanofiber membrane is 0 After the combination, the particle size of the electrospun fibers increased significantly and the red fluorescence was enhanced. 0 The fluorescence turn-on performance after the reaction can realize Pd 0 Rapid detection.

[0035] In addition, the fluorescent nanofiber membrane has the characteristics of simple preparation, low cost, and reusability, which can realize the 0 Faster detection. After the electrospun film containing the probe reacts with the palladium element, the color development time is shortened to about 10 seconds. The change in fluorescence color can be observed by the naked eye under ultraviolet light, and it is no longer dependent on the detection of large instruments, thus realizing the detection of Pd in ​​the environment. 0 It provides a powerful tool for rapid and simple detection and has extremely broad application prospects in the field of palladium element detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 The fluorescent probe used in the present invention detects Pd 0 Diagram of the detection mechanism;

[0037] Figure 2 The fluorescence spectrum change diagram of the fluorescent probe in the present invention after reacting with different metal ions;

[0038] Figure 3 The fluorescent probe in the present invention is different from different metal ions and Pd 0 Fluorescence spectrum changes after the common reaction;

[0039] Figure 4 The fluorescent probe and Pd 0 Fluorescence intensity changes with reaction time;

[0040] Figure 5 The fluorescent probe and Pd 0 Fluorescence intensity changes of the reaction under different pH conditions;

[0041] Figure 6 Different concentrations of Pd are added to the fluorescent probe of the present invention. 0 UV spectrum of the solution;

[0042] Figure 7 Different concentrations of Pd are added to the fluorescent probe of the present invention. 0 Fluorescence spectrum of the solution;

[0043] Figure 8 The fluorescence intensity of the fluorescent probe at 641 nm in the present invention is the same as that of Pd 0 Linear relationship graph between concentrations;

[0044] Fig. 9 The fluorescent nanofiber membrane and Pd 0 Changes in fluorescence intensity attached to the fiber membrane before and after the reaction;

[0045] Fig.10 The fluorescent nanofiber membrane and Pd 0 Scanning electron microscopy images before (a, b) and after (c, d) the reaction;

[0046] Fig.11 The fluorescent nanofiber membrane and Pd 0 Nanofiber diameter distribution before (a) and after (b) reaction. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. The test methods used in the following embodiments are conventional methods unless otherwise specified; the raw materials used are all commonly used in the field, available to the public or commercially available, unless otherwise specified.

[0048] In the embodiments of the present invention, all solvents used are commercially available chemically pure or analytically pure. In the present invention, "room temperature" refers to the room temperature commonly understood in the art, generally 15-30°C.

[0049] In the embodiment of the present invention, allyl chloroformate was purchased from Shanghai Haohong Biopharmaceutical Technology Co., Ltd. The compound of formula (II) was conventionally prepared and its structure was confirmed with reference to the prior art (A novel near-infrared fluorescent probe for the detectionof sulfur dioxide derivatives and its application in biological imaging[J]New J. Chem., 2022, 46,10746). Polyvinyl butyral was purchased from Qingdao Nuokang Environmental Protection Technology Co., Ltd., model 120S.

[0050] In the embodiment of the present invention, the structure of the compound is determined by nuclear magnetic resonance (NMR) technology. The NMR measurement uses a Bruker nuclear magnetic resonance instrument. The solvent used in the measurement is DMSO-d6, and the internal standard is TMS.

[0051] Example 1

[0052] This embodiment provides a fluorescent probe for detecting metal palladium, whose molecular formula is C 27 H 26 ClNO8, specifically a compound of the structure shown in formula (I):

[0053] Formula (I).

[0054] The preparation method of the fluorescent probe for detecting metal palladium is shown in the following formula, which specifically comprises the following steps:

[0055]

[0056] The compound of formula (II) (named WL-OH, 500 mg, 1.129 mmol) and three drops of triethylamine were added to anhydrous dichloromethane (20 mL), and allyl chloroformate (0.24 mL, 2.258 mmol) was slowly added at room temperature. The mixture was reacted at room temperature for 5 min, and then concentrated by rotary evaporation. Column chromatography was performed (elution phase: dichloromethane: methanol = 500: 1) to obtain a purple-black solid powder (183 mg), which was the fluorescent probe for detecting metal palladium in Example 1 (named WL), with a yield of 44%.

[0057] The purple-black powder solid obtained above was subjected to nuclear magnetic resonance analysis, thereby identifying the exact structure of the fluorescent probe for detecting metal palladium in Example 1. The hydrogen spectrum analysis result of nuclear magnetic resonance is: 1 H NMR (DMSO-d6, 600 MHz) δ8.47 (s, 1H), 8.16 (d, J = 8.9 Hz, 1H), 7.59 (s, 1H), 7.44 (d, J = 10.5 Hz,2H), 6.06 - 5.99 (m, 1H), 5.46 - 5.42 (m, 1H), 5.35 (d, J = 11.8 Hz, 1H),4.78 (s, 2H), 3.62 (q, J = 5.6 Hz, 4H), 3.08 - 3.02 (m, 6H), 2.91 (t, J = 5.9Hz, 2H), 2.03 - 1.96 (m, 4H). The results of carbon nuclear magnetic resonance analysis are: 13C NMR (151 MHz, DMSO-d6) δ 159.00, 154.39, 153.24, 152.67, 146.41, 143.40, 132.07, 130.12, 129.63,127.43, 126.99, 125.13, 122.17, 121.39, 120.27, 119.63, 105.00, 69.59, 51.24, 50.81, 29.30, 27.47, 26.65, 24.61, 20.22, 19.34.

[0058] This embodiment also provides the above-mentioned fluorescent probe for detecting metal palladium as a molecular probe in palladium (Pd 0 ) detection. This fluorescent probe detects Pd 0 The detection mechanism of Figure 1 shown. Figure 1 First, the fluorescent probes WL and Pd 0 An oxidative addition reaction occurs to generate intermediate 1. Then, intermediate 1 dissociates to form unstable intermediate 2, which then undergoes a decarboxylation reaction to generate compound WL-OH.

[0059] Example 2

[0060] This embodiment provides a fluorescent nanofiber membrane for detecting metal palladium, which is prepared by a method comprising the following steps:

[0061] (1) Preparation of spinning solution: Under room temperature, prepare a clear, transparent, bubble-free polymer solution with a mass fraction of 8%, wherein the polymer in the polymer solution is polyvinyl butyral. Add 10 mg of the fluorescent probe prepared in Example 1 to 10 mL of the polymer solution, stir and mix for 12 h, and obtain a spinning solution.

[0062] (2) Preparation of fluorescent nanofiber membrane by electrospinning: The spinning solution prepared in the previous step is placed in a syringe for electrospinning. During the electrospinning process, the spinning solution is loaded into a 5 mL syringe, a No. 24 blunt needle is used as a spinneret, and filter paper is used as a collector. The spinning solution is electrospun at a constant flow rate of 2.5 mL / h and a spinning voltage of 15 KV. Finally, the fibers obtained by spinning are collected on an aluminum foil at a distance of 10 cm to obtain the fluorescent nanofiber membrane for detecting metal palladium in this embodiment.

[0063] This embodiment also provides the fluorescent nanofiber membrane for detecting metal palladium on Pd 0 Application in detection.

[0064] Experimental Example 1: Fluorescent Probe and Pd 0Spectral response

[0065] 1. Screening of test system

[0066] In this experiment, commonly used solvents (methanol, ethanol, N,N-dimethylformamide, dimethyl sulfoxide, acetonitrile) were mixed with PBS at different volume ratios, and then the fluorescence probe of Example 1 was tested for Pd 0 The test results show that the fluorescent probe of Example 1 has a strong affinity for Pd 0 Among them, the acetonitrile / PBS (pH=7.4, v / v=3:7) system is the solvent system with the strongest fluorescence response. This confirms that the fluorescent probe can be used for Pd 0 Detection.

[0067] 2. Selectivity and anti-interference test

[0068] Accurately pipette 3 mL of spectral solution (composition: acetonitrile: PBS = 3:7) into the cuvette, take 60 μL of the probe mother solution (DMSO prepared, concentration is 1 mM) prepared by the fluorescent probe in Example 1 into the cuvette, and then add different ion solutions (Mn 2+ ,Mg 2+ ,Co 2+ , Zn 2+ , NH4 + , Cu 2+ , Na + , Ag + , K + , Cs 2+ , SO4 2- , NO3 - , Pd 0 ) 60μL each, and measure the fluorescence intensity at 641nm. Among them, the ion solution is 10mM stock solution prepared with deionized water. The test results are as follows Figure 2 shown. Figure 2 The meanings of the bars corresponding to numbers 1-14 are as follows: 1. The control group containing only the spectral solution and the probe mother solution without adding the ion solution; 2. Mn 2+ 3. Mg 2+ ; 4. Co 2+ ; 5. Zn 2+ ; 6. NH4 + ; 7. Cu 2+ ; 8. Na + ; 9. Ag + ; 10. K + ; 11. Cs 2+ ; 12. SO4 2- ; 13. NO3- ; 14. Pd 0 .

[0069] Depend on Figure 2 It can be seen that compared with the control group, the fluorescence intensity of the other ions changed very slightly, while the addition of Pd 0 The fluorescence intensity changes significantly after that, which indicates that the fluorescent probe is sensitive to Pd 0 Has good single selectivity.

[0070] Further, 3 mL of spectral solution (composition: acetonitrile: PBS = 3:7) was accurately transferred into the cuvette, and 60 μL of the probe mother solution (prepared in DMSO, concentration of 1 mM) prepared by the fluorescent probe of Example 1 and 60 μL of Pd 0 After the mother solution (prepared in tetrahydrofuran, 10 mM) was added to the cuvette, 60 μL of different ions (Mn 2+ , Mg 2+ , Co 2+ , Zn 2+ ,NH4 + , Cu 2+ , Na + , Ag + , K + , Cs 2+ , SO4 2- , NO3), and measured the fluorescence intensity at 641nm. The results are as follows Figure 3 shown. Figure 3 The meanings of the bars corresponding to numbers 1-13 are as follows: 1. Contains only spectral solution, probe mother solution and Pd 0 Mother solution, control group without adding other ion solutions; 2. Mn 2+ 3. Mg 2+ ; 4. Co 2+ ; 5. Zn 2+ ; 6. NH4 + ; 7. Cu 2+ ; 8. Na + ; 9.Ag + ; 10. K + ; 11. Cs 2+ ; 12. SO4 2- ; 13. NO3 - .

[0071] Depend on Figure 3 It can be seen that after adding other potential interfering substances, the probe recognizes Pd 0 The change of the fluorescence signal of the present invention is very small, indicating that the fluorescent probe of the present invention detects Pd 0 The anti-interference ability is good.

[0072] 3. Time response experiment

[0073] The fluorescent probe of Example 1 (20 μM, prepared in DMSO) was mixed with Pd 0 (180 μM, prepared in tetrahydrofuran) were incubated for 60 min. The fluorescence spectrum was recorded every three minutes for the first 25 min and every 5 min thereafter. The results are shown in Figure 4 As shown. Figure 4 It can be seen that the fluorescent probe of the present invention and Pd 0 The response was complete in about 15 minutes.

[0074] 4. Effect of different pH on fluorescent probes

[0075] The fluorescent probe of Example 1 (20 μM, prepared in DMSO) was mixed with Pd 0 (180 μM, prepared in tetrahydrofuran) was incubated for 15 min under different pH conditions and the spectra were recorded. The results are shown in Figure 5 As shown in Figure 2, the fluorescent probe has almost no fluorescence intensity at pH 2-12. 0 After that, the fluorescence intensity increased significantly in the pH range of 6-9, indicating that the probe can effectively detect Pd in ​​the pH range of 6-9. 0 .

[0076] 5. Pd 0 Effect of concentration on the detection effect of fluorescent probe

[0077] The fluorescent probe prepared in Example 1 was prepared into a probe mother solution with a concentration of 1 mM using dimethyl sulfoxide (DMSO) as a solvent; then Pd 0 Dissolve Pd to a concentration of 10 mM 0 Accurately pipette 3 mL of spectral solution (composition: acetonitrile: PBS = 3:7) into the cuvette, then take 60 μL of probe mother solution and add it to the cuvette (the final concentration of the probe is 20 μM), and then add different concentrations of Pd 0 Mother liquor, added Pd 0 The concentration of the mother solution was 0-180 μM. After 20 min of reaction, the probe was tested by UV-visible spectrometer. 0 The change of UV absorption value after solution was tested by fluorescence spectrometer after adding different concentrations of Pd 0 The change of fluorescence intensity after solution was obtained, and the UV spectra were obtained respectively (such as Figure 6 ) and fluorescence spectra (as shown in Figure 7 as shown).

[0078] Depend on Figure 6 It can be seen that in Pd 0When the concentration is 0, the ultraviolet absorption peak of the fluorescent probe at 600nm is very weak. 0 With the increase of concentration, the ultraviolet absorption peak at 600nm gradually increases.

[0079] Depend on Figure 7 It can be seen that in Pd 0 When the concentration is 0, there is almost no fluorescence emission at 641nm. 0 With the increase of concentration, the fluorescence intensity at 641nm gradually increased.

[0080] Through further data processing, the fluorescence intensity of the fluorescent probe at 641 nm and the fluorescence intensity of Pd 0 The linear relationship between the concentrations, such as Figure 8 As shown, the fluorescence intensity is related to Pd 0 The concentration showed a good linear relationship in the range of 0-60 μM, and the fitting constant R 2 =0.9866. From the above experimental data, it can be seen that the probe has a good effect on Pd 0 It does have a good recognition effect.

[0081] Depend on Figure 6 , Figure 7 Combination Figure 8 The experimental results show that the fluorescent probe of the present invention has a strong affinity for Pd 0 It has good recognition effect and shows concentration-dependent effect.

[0082] Experimental Example 2: Combination of fluorescent probe and electrospinning technology

[0083] Example 2 of the present invention uses an electrospinning process to produce a Pd detection 0 In order to study the fluorescent nanofiber membrane of Example 2 exposed to Pd 0 After the fluorescence change, the film was immersed in 100 μM Pd 0 The color development result was observed under 365nm ultraviolet light after 10s. Fig. 9 For fluorescent nanofiber membrane and Pd 0 The change of fluorescence intensity attached to the fiber membrane before and after the reaction, Fig. 9 The upper figure is the fluorescence image before the reaction, and the lower figure is the fluorescence image after the reaction.

[0084] like Fig. 9 As shown, the fluorescent nanofiber membrane itself has almost no fluorescence, which is different from the Pd 0 Strong red fluorescence was observed after the reaction. These results indicate that the electrospun film containing the probe is 0After the reaction, the change of fluorescence color can be observed by naked eyes under 365nm ultraviolet light, which is no longer dependent on the detection of large instruments, and the color development time is shortened to about 10s. This shows that the fluorescent probe of the present invention has good compatibility with the nanofiber membrane and can be used to detect Pd 0 .

[0085] At the same time, the fluorescent nanofiber membrane of Example 2 and 100 μM Pd 0 The morphology before and after the reaction is as follows Fig.10 As shown, Fig.10 In the figure, a and b are the fluorescence nanofiber membrane and Pd at different magnifications. 0 SEM images before reaction; c and d are the fluorescent nanofiber membrane and Pd at different magnifications. 0 Scanning electron microscopy images after reaction.

[0086] Depend on Fig.10 As can be seen from a, b, c, and d, the film is composed of a large number of randomly arranged nanofibers.

[0087] Further, the detection of Pd in ​​Example 2 0 Fluorescent nanofiber membrane with Pd 0 The nanofiber diameter distribution before and after the reaction was tested. The nanofiber diameter distribution results before and after the reaction were as follows: Fig.11 As shown in a and b.

[0088] Depend on Fig.11 It can be seen that the average diameter of the nanofibers in the fluorescent nanofiber film of Example 2 is 0.5249±0.0736μm (a), and the distribution is uniform. 0 After the solution reaction, the average diameter of the nanofibers in the nanofiber film increased to 1.0196±0.1483μm (b). These results show that the fluorescent probe in the fluorescent nanofiber film is closely related to Pd 0 The solution reacts, causing the particle size of the nanofibers in the nanofiber membrane bound by the probe to increase and change their morphology.

[0089] In summary, the fluorescent probe for detecting metallic palladium provided by the present invention has benzopyran as the fluorescent parent nucleus and allyl as the recognition site, has a novel structure, and can effectively detect elemental palladium in the environment. Furthermore, the fluorescent nanofiber membrane for detecting metallic palladium provided by the present invention effectively combines electrospinning technology with fluorescent probes, and utilizes fluorescent probes to detect Pd 0 The fluorescence turn-on performance after the reaction can realize Pd 0 In addition, the fluorescent nanofiber membrane has the characteristics of simple preparation, low cost and reusability, which can realize the rapid detection of Pd in ​​the environment. 0It provides a powerful tool for rapid and simple detection of palladium and has extremely broad development prospects in the field of palladium detection.

[0090] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fluorescent nanofiber membrane for detecting metallic palladium, characterized in that: The method is prepared by the following steps: The fluorescent probe for detecting metal palladium is mixed evenly with a high molecular polymer solution to obtain a spinning solution; the spinning solution is subjected to an electrostatic spinning process to obtain a fluorescent nanofiber membrane for detecting metal palladium; Wherein, the metal palladium is a single substance of palladium; in the polymer solution, the polymer used is polyvinyl butyral; and the fluorescent probe for detecting the metal palladium is a compound having a structure shown in formula (I): Formula (I).

2. The fluorescent nanofiber membrane for detecting metallic palladium according to claim 1, characterized in that: The dosage ratio of the fluorescent probe for detecting metal palladium to the high molecular polymer solution is 1 mg: (0.8~1.2) mL.

3. The fluorescent nanofiber membrane for detecting metallic palladium according to claim 1, characterized in that: The mass concentration of the high molecular polymer solution is 7% to 9%.

4. The fluorescent nanofiber membrane for detecting metallic palladium according to claim 1, characterized in that: The process conditions of the electrospinning treatment are: the spinning voltage is 10kV~20kV, and the spinning solution flow rate is 2~3mL / h.

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