Cationic polythiophene derivative and method for detecting and removing perchlorate and pertechnetate

Abstract

The present invention relates to the field of anion pollutant detection and repair technology, and in particular to a cationic polythiophene derivative and method for detecting and removing perchlorate and pertechnetate. The water-soluble cationic polythiophene probe provided by the present invention is light yellow and has yellow fluorescence. When ClO is added, 4 ‑ , TcO 4 ‑ After the anion, the color of the solution quickly changes from yellow to purple-red, and the fluorescence color changes from yellow to red or quenches. ClO can be realized through the changes in absorption spectrum, fluorescence spectrum and intensity. 4 ‑ , TcO 4 ‑ Highly sensitive and specific qualitative and quantitative detection of anions. 4 ‑ , TcO 4 ‑ The change of molecular aggregation state after anion binding can be achieved by ultrafiltration, microfiltration, dialysis and precipitation. 4 ‑ , TcO 4 ‑ Rapid and efficient removal of anions.

Description

Technical Field

[0001] The present invention relates to the field of anion pollutant detection and repair technology, and in particular to a perchlorate and pertechnetate rapid (ClO4 - 、TcO4 - )Visual dual-mode detection and removal method. Background Art

[0002] Water is an important resource required for the survival of all living things, including humans, and is the most important material component of organisms. The so-called water pollution generally refers to the phenomenon that a certain substance enters the water body and affects the effective use of water, causing the deterioration of water quality. Due to the long-term discharge of sewage (wastewater) into natural water bodies during people's lives and industrial activities, the limited self-purification capacity of water bodies is unable to bear, thus causing serious water pollution problems. Research results show that the current water pollution problems are mainly caused by chemical pollutants. Among the chemical pollutants that may cause water pollution, some pollutants exist in the polluted water body in the form of anions, and have direct or potential harm to the water ecological environment and human health. There are many pollutants in the form of anions in water, most of which have certain potential or significant toxicity and can cause water environmental problems to varying degrees.

[0003] Perchlorate is an environmental pollutant with high stability, high solubility, high diffusivity, oxidizability and non-volatility. It is mainly used as rocket fuel, oxidant in fireworks and explosive in airbags. Because of its high stability and difficulty in degradation, exposure to the environment will lead to long-term pollution of water sources and soil. After enrichment or transformation, it enters the human body through breathing, food chain and other pathways. Since perchlorate has similar charge and ionic radius to iodine ions, it will inhibit the absorption and utilization of iodine by the thyroid gland after ingestion into the human body, causing a decrease in the secretion of thyroid hormones, affecting the normal function, metabolism and development of the thyroid gland, and endangering human health. The GB5479-2022 Drinking Water Hygiene Standard, which was implemented by the state on April 1, 2023, stipulates that the residual amount of perchlorate in water is 0.07 mg / L, and the European Food Safety Authority expert group sets a daily limit of 0.3 μg / kg (body weight) for perchlorate in food to ensure the safety of drinking water resources and food. Therefore, efficient, sensitive and specific detection methods for perchlorate are of great significance in the fields of food safety, environmental protection and public health.

[0004] At present, the methods developed for the detection of perchlorate include ion chromatography-mass spectrometry, portable Raman spectroscopy, electrochemical methods, etc. However, these detection methods have the disadvantages of being easily interfered, complicated to operate, expensive equipment, and requiring high laboratory hardware conditions and personnel quality.

[0005] The method of detecting perchlorate by using the photochemical properties of materials has attracted widespread attention due to its advantages such as rapidity and high sensitivity. Most of the methods based on colorimetric detection of perchlorate detect perchlorate by color change caused by the interaction between phenothiazine derivative dye-methylene blue (MB) and perchlorate. Amisar et al. (US Patent: US Patent, 2011, 13146261) invented a kit for detecting oxidants in explosives, which mainly uses absorption test paper to absorb methylene blue solution to enhance the detection of ClO4 - The color changes when the sample is exposed. Peters et al. (Forensic Chemistry, 2018, 9, 35) developed a microfluidics-based paper-based analytical device (μPAD) for on-site colorimetric sensing of explosives. The methylene blue aqueous solution at the top of the sample channel reacts with perchlorate and the color changes from blue to purple. Although the colorimetric sensing is simple to operate and low in cost, its low sensitivity and susceptibility to interference are still urgent to be solved. By utilizing the weak hydration characteristics of perchlorate and adjusting the material structure, ultra-sensitive detection of perchlorate can be achieved. Dou et al. (Chinese patent: CN202210354400.7) adjusted the van der Waals force between perchlorate and the probe molecule by adjusting the alkyl chain length of the styrene derivative to achieve ultra-sensitive sensing of perchlorate (53.81nM). The research group also designed a sensor molecule for phosphorescence changes - bromoplatinum (II) terpyridine complex (Chinese patent: CN202110211918.0). In the presence of perchlorate, it induces the sensor molecule to self-assemble, promotes Pt-Pt metal-metal interaction, and π-π interaction, thereby achieving ultra-sensitive sensing of perchlorate (2.5×10 -8 M).

[0006] In order to meet the growing demand for sensing technology and overcome the problems of strong background interference and limited application of single sensing, a method for developing fluorescence colorimetric dual-mode sensing technology has been proposed, which has attracted widespread attention. The Dou team (Journal of Materials Chemistry A, 2022, 10, 8195) achieved fluorescence colorimetric dual-mode sensing of perchlorate by adjusting the monoanionic ligand and counteranion in the Pt(II) terpyridine complex. The integration of dual-mode sensing not only improves analytical efficiency and reduces assumptions, but also improves analytical performance, expands the detection linear range, improves accuracy, and increases application flexibility.

[0007] In addition to the detection needs, the removal of perchlorate, a persistent pollutant in water, has an important impact on protecting human health and restoring environmental ecology. Researchers have established many removal technologies for perchlorate: adsorption, ion exchange, membrane filtration, chemical reduction, electrochemical reduction, catalytic reduction, etc. (Food Chemistry, 2021, 360, 130146). Zheng (Chemical Engineering Journal, 2020, 380, 122580) led the team to design and construct a water-stable cationic porous coordination polymer. The complex has a significant spatial confinement effect on perchlorate ions, and exhibits rapid adsorption kinetics (30min) and a large adsorption capacity (108.70mg / g) for perchlorate, with good repeatability and high selectivity. This method is only for adsorption removal when perchlorate is heavily polluted, and does not involve the removal effect of trace perchlorate pollution.

[0008] Compared with traditional fossil fuel power generation, nuclear power generation is clean, efficient and safe, which greatly alleviates the problem of energy shortage. At present, uranium / plutonium fission nuclear energy is one of the best choices to replace fossil fuel energy, but the gradual increase of radioactive nuclear waste and its derived pollutants has brought potential long-term risks to human health and the environment. Technetium-99( 99 Tc), a radioactive element commonly found in nuclear waste, is generated from uranium-235( 235 U) and plutonium-239 ( 239 Pu) thermal fission and uranium-238 ( 238 U) Produced by spontaneous fission. 99 Tc has a long half-life (2.13×10 5 ) and high fission yield (6.1%), excessive contact 99 Tc can cause diseases such as skin diseases, ulcers and cancer. In oxygenated water environments, 99 Tc is mainly present in the form of pertechnetate ( 99 TcO4 - ) exists in the form of. 99 TcO4 - Due to the high solubility of and the low adsorption of by earth minerals, 99 TcO4 - It has high environmental mobility and can easily lead to serious 99 Tc pollution. If not dealt with in time 99 Tc contamination makes 99 TcO4 - Migration into natural water bodies will cause unpredictable damage to the ecological environment. On the other hand, due to its unique chemical structure and properties, 99Tc plays an extremely important role in the development of new radiopharmaceuticals and nuclear medicine. Therefore, rapid identification / adsorption / extraction of pertechnetate is of great significance for nuclear waste treatment, environmental decontamination, technetium resource recovery and human health. At present, a variety of pertechnetate recognition and adsorption materials have been developed, such as precipitation, ion exchange and supramolecular recognition materials, but there is room for improvement in adsorption selectivity, adsorption kinetics, physicochemical stability, etc. (China Science Foundation 2019, 33, 592-600), and the recognition materials that can simultaneously detect and separate pertechnetate are very limited. Summary of the invention

[0009] The present invention aims to solve the problem of perchlorate / pertechnetate (ClO4 - 、TcO4 - ) The lack of highly sensitive and selective identification materials for anions provides a method for simultaneously detecting and removing ClO4 - 、TcO4 - Anionic cationic polythiophene derivatives and methods.

[0010] The technical solution of the present invention is as follows:

[0011] A cationic polythiophene derivative for detecting and removing perchlorate and pertechnetate, the structure of which is shown in formula (I) and formula (II):

[0012]

[0013] Formula (I) is a homopolymer structure, R1 is H or CH3; R2 is O or CH2; R3 is an alkyl group with an integer of carbon number between 1 and 6 and its isomers: methyl, ethyl, propyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, isohexyl; R4 is H or CH3; m is an integer between 0 and 15; M is Cl or Br; n is a positive integer, and the weight average molecular weight of the polythiophene derivative is 3,000 to 50,000;

[0014] Formula (II) consists of thiophene units connected at the 2 and 5 positions to form a conjugated main chain, and its structural formula is shown below:

[0015]

[0016] Formula (II) is a copolymer structure, R1 is H or CH3; R2 is O or CH2; m is an integer between 0 and 15; M is Cl or Br; R 1# ,R 2# ,R 3# ,R 4# , selected from R in the above formula (I) #Substituents, wherein R3 is an alkyl group with an integer carbon number between 1 and 6 and its isomers: methyl, ethyl, propyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, isohexyl; R4 is H or CH3; and satisfies R 1# ≠R 2# ≠R 3# ≠R 4# ; n1, n2, n3, n4 are integers between 1 and 500, and make the weight-average molecular weight of the polythiophene derivative be between 3,000 and 100,000.

[0017] A method for detecting perchlorate and pertechnetate using the cationic polythiophene derivative comprises the following steps:

[0018] (1) dissolving 5 μmol of formula (I) and formula (II) in 100 mL of ultrapure water to obtain a probe molecule solution;

[0019] (2) adding the probe obtained in step (1) into a cuvette of uniform volume to obtain a detection reagent;

[0020] (3) ClO4 - 、TcO4 - After the standard solution reacts with the reagent obtained in step (2), the changes in its UV-visible absorption spectrum and fluorescence spectrum are measured. The peak changes correspond to the ClO4 - 、TcO4 - Quantitative analysis of the linear relationship between concentration values;

[0021] (4) Add ClO4 to the detection reagent in step (2) - 、TcO4 - After that, the UV absorption peak of the probe molecule will be red-shifted. - 、TcO4 - As the concentration increases, the peak at 545nm gradually increases, and at the same time, the fluorescence characteristic absorption peak of the probe molecule is quenched and red-shifted, and the overall detection time is less than 10s.

[0022] Furthermore, this method can detect ClO4 - 、TcO4 - The concentration range is 0.1-1×10 4 The concentration of the probe molecule solution ranged from 0.1 to 100 μM.

[0023] Furthermore, the volume of the detection reaction system is 200-3000 μL; the reaction temperature is 4-40° C.; the pH value of the reaction system is 4-14; and the detection reaction is carried out in pure water, organic solvents: methanol, ethanol, acetonitrile, and buffer solution HEPES.

[0024] A method for removing perchlorate and pertechnetate using the cationic polythiophene derivative comprises the following steps:

[0025] (1) dissolving the compound of formula (I) / formula (II) in ultrapure water to obtain a probe molecule solution;

[0026] (2) Add the probe molecule prepared in step (1) to a solution containing ClO4 - 、TcO4 - The reaction was carried out in water;

[0027] (3) After the reaction is completed, the solution is added to the removal system for separation and removal, and the sample after removal is analyzed to obtain the probe molecule to remove ClO4 - 、TcO4 - efficiency.

[0028] Furthermore, ClO4 - 、TcO4 - When the concentration is 0.5-100mM, the probe molecule is separated and removed by precipitation. - 、TcO4 - The molar ratios are 0.5:1, 1:1, and 1.5:1.

[0029] Furthermore, ClO4 - 、TcO4 - When the concentration is 5-50 μM, microfiltration is used for separation and removal. The types of filter membranes include but are not limited to: PES, PVDF, PTFE, PC, PP, Nylon66; the pore size of the filter membrane includes but is not limited to 0.2-0.45 μm.

[0030] Furthermore, ClO4 - 、TcO4 - When the concentration is 0.1-20 μM, an ultrafiltration system is used for separation and removal, and the pore size of the ultrafiltration system includes but is not limited to: 3-300 kDa.

[0031] Furthermore, ClO4 - 、TcO4 - When the concentration is 2-50 μM, a dialysis bag is used for separation and removal, and the pore size of the dialysis bag includes but is not limited to 8-50 kDa; the material of the dialysis bag includes but is not limited to cellulose ester CE, regenerated cellulose RC, and PVDF.

[0032] The beneficial effects of the present invention are embodied in:

[0033] The probe molecule developed by the present invention can react with ClO4 - 、TcO4 - The combination of anions causes the color and optical properties of the solution to change, which can be used to treat ClO4 - 、TcO4- The anions are specifically and sensitively detected by colorimetry and fluorescence sensing. At the same time, the molecular structure aggregation after the probe molecules bind to the anions is used to achieve the removal of anions in water. The probe molecules developed by the present invention have the advantages of stable structure, good water solubility, rapid response, etc., and can achieve synchronous dual-mode detection and removal of anions in water. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a structural diagram of the thiophene monomer synthesized in Example 1 of the present invention.

[0035] Figure 2 In Example 2 of the present invention, different R 1 Substituent-based probe molecule of formula (I) for detecting ClO4 - The effect diagram, A) is listed as different PT names and different R 1 Structural differences of substituents; B) is a schematic diagram of colorimetry and absorption spectrum sensing; C) is a schematic diagram of fluorescence colorimetry and fluorescence spectrum sensing.

[0036] Figure 3 The probe molecule of formula (I) with different carbon chain length m in Example 2 of the present invention detects ClO4 - Effect diagram, A) lists different PT names and different carbon chain m lengths; B) is a schematic diagram of colorimetry and absorption spectrum sensing; C) is a schematic diagram of fluorescence colorimetry and fluorescence spectrum sensing.

[0037] Figure 4 In Example 2 of the present invention, different R # Substituent-based probe molecule of formula (I) for detecting ClO4 - The effect diagram, A) is listed as different PT names and different R # Structural differences of substituents; B) is a schematic diagram of colorimetry and absorption spectrum sensing; C) is a schematic diagram of fluorescence colorimetry and fluorescence spectrum sensing.

[0038] Figure 5 The method for detecting ClO4 by changing the solvent type in Example 2 of the present invention - Schematic diagram of the effect, A) shows different solvent compositions; B) shows the schematic diagram of colorimetry and absorption spectrum sensing; C) shows the schematic diagram of fluorescence colorimetry and fluorescence spectrum sensing.

[0039] Figure 6 In Example 2 of the present invention, probe molecules of different structures (II) are used to detect ClO4 - Effect diagram, A) lists the names of different PTs and the differences between different monomers and polymerization ratios; B) is a schematic diagram of colorimetry and absorption spectrum sensing; C) is a schematic diagram of fluorescence colorimetry and fluorescence spectrum sensing.

[0040] Figure 7The UV-visible absorption spectrum of the probe molecule in Example 3 of the present invention is different from that of ClO4 - The relationship between the concentrations, A) is the probe molecule (50 μM) and different equivalents of ClO4 - UV-visible absorption spectrum of the effect; B) is the probe molecule on ClO4 - Sensitivity recognition diagram; C) Probe molecule and ClO4 - Visualization under fluorescent light; D) Different concentrations of ClO4 - The B / (R+G) value of the probe molecule under fluorescent light irradiation; E) The probe molecule (PT) and trace ClO4 under ultrafiltration preconcentration. - (0.1 μM) Absorbance bar graph before and after the reaction; F) In the case of evaporation pre-concentration, the probe molecule (PT) reacts with trace ClO4 - (0.1 μM) Absorbance bar graph before and after the reaction.

[0041] Figure 8 In Example 3 of the present invention, the probe molecule is sensitive to anions (ClO4 - 、TcO4 - ) is the selectivity investigation process, A) is the probe molecule (PT) and anion (ClO4 - 、TcO4 - ) and the color change diagram of the solution of interfering ion reaction (sequence number in the figure: 1PT, 2Cl - 3NO2 - 、4IO3 - , 5F - 、6HCO3 - 7CO3 2- 、8HPO4 2- 、9H2PO4 - 10NO3 - 、11BrO3 - 、12ClO2 - 、13ClO3 - 、14SO4 2- 、15P2O7 4- 、16ClO4 - 、17ReO4 - (TcO4 - )、18SCN - 、19I - , the same below); B) Histogram of absorbance ratios of the probe molecule to anions and other interferents.

[0042] Fig. 9 The fluorescence spectrum change of the probe molecule in Example 4 of the present invention and ClO4 -The relationship between the concentrations, A) is the probe molecule (5 μM) and different equivalents of ClO4 - B) is the fluorescence spectrum of the probe molecule and ClO4 - The wavelength red shift after the action; C) The fluorescence intensity at 540nm changes with ClO4 - Fluorescence quenching diagram with increasing concentration (quenching rate Q% = (I0-I) / I0*100, where I0 is the initial fluorescence intensity of the probe molecule, I is the concentration of ClO4 added - The fluorescence intensity after that).

[0043] Fig.10 In Example 4 of the present invention, the probe molecule is sensitive to anions (ClO4 - 、TcO4 - ) is the selectivity investigation process, A) is the probe molecule and anion (ClO4 - 、TcO4 - ) and the fluorescence color change diagram of the interfering substance reaction (sequence number in the figure: 1PT, 2Cl - 3NO2 - 、4IO3 - , 5F - 、6HCO3 - 7CO3 2- 、8HPO4 2- 、9H2PO4 - 10NO3 - 、11BrO3 - 、12ClO2 - 、13ClO3 - 、14SO4 2- 、15P2O7 4- 、16ClO4 - 、17ReO4 - (TcO4 - )、18SCN - 、19I - , the same below); B) fluorescence intensity diagram of the interaction between the probe molecule and anions and other interferents under different excitations (420, 470, 550nm);

[0044] Fig.11 The probe molecule in Example 5 of the present invention is ClO4 - Removal effect diagram, A) ClO4 added to the probe molecule - Transmission electron micrographs before and after; B) ClO4 was added to the probe molecule - Dynamic light scattering (DLS) comparison before and after; CD precipitation to remove ClO4 - (Figure C: Flow chart, Figure D: Precipitation to remove ClO4- Effect diagram); EF microfiltration to remove ClO4 - (Figure E: Flow chart, Figure F: Microfiltration to remove ClO4 - Effect diagram); GH ultrafiltration to remove ClO4 - (Figure G: Flow chart, Figure H: Ultrafiltration to remove ClO4 - Effect diagram); IJ dialysis to remove ClO4 - (Figure I: Flow chart, Figure J: Dialysis to remove ClO4 - effect diagram).

[0045] Fig.12 Effect diagram of recycling probe molecules in Example 6 of the present invention, A) schematic diagram of the principle of recycling probes; B) effect diagram of recycling probe molecules.

[0046] Fig.13 The probe molecule in Example 7 of the present invention is ReO4 - / TcO4 - Detection comparison chart, A) is the probe molecule (50μM) and different equivalents of TcO4 - UV-visible absorption spectra of the effect; B) is the probe molecule (50μM) and different equivalents of ReO4 - UV-visible absorption spectrum of the effect.

[0047] Fig.14 The probe molecule in Example 8 of the present invention is ReO4 - / TcO4 - Removal effect diagram, A) Removal of ReO4 by precipitation - / TcO4 - Effect diagram, B) ReO4 removal by microfiltration (MF) - / TcO4 - Effect diagram; C) Ultrafiltration (UF) removal of ReO4 - / TcO4 - Effect diagram; D) ReO4 removal by dialysis - / TcO4 - Effect picture. DETAILED DESCRIPTION

[0048] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. The embodiments are only used to explain the present invention rather than to limit the present invention.

[0049] The water-soluble cationic polythiophene probe provided by the present invention is light yellow and has yellow fluorescence. - 、TcO4 -After the anion, the color of the solution quickly changes from yellow to purple-red, and the fluorescence color changes from yellow to red or quenches. ClO4 can be realized through the changes in absorption spectrum, fluorescence spectrum and intensity. - 、TcO4 - Highly sensitive and specific qualitative and quantitative detection of anions. - 、TcO4 - The change of molecular aggregation state after anion binding can be achieved by ultrafiltration, microfiltration, dialysis and precipitation. - 、TcO4 - Rapid and efficient removal of anions.

[0050] Example:

[0051] First, the present invention provides cationic polythiophene derivatives represented by formula (I) and formula (II).

[0052]

[0053] Formula (I) is a homopolymer structure, R1 is H or CH3; R2 is O or CH2; R3 is an alkyl group with an integer carbon number between 1 and 6 and its isomers (methyl, ethyl, propyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, isohexyl); R4 is H or CH3; m is an integer between 0 and 15; M is Cl or Br; n is a positive integer, and the weight average molecular weight of the polythiophene derivative is between 3,000 and 50,000.

[0054] Formula (II) is composed of thiophene units connected at the 2 and 5 positions to form a conjugated main chain, and its structural formula is shown below:

[0055]

[0056] Formula (II) is a copolymer structure, R1 is H or CH3; R2 is O or CH2; m is an integer between 0 and 15; M is Cl or Br; R 1# ,R 2# ,R 3# ,R 4# , selected from R in the above formula (I) # Substituents, wherein R3 is an alkyl group having an integer of 1 to 6 carbon atoms and its isomers (methyl, ethyl, propyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, isohexyl); R4 is H or CH3; and R 1# ≠R 2# ≠R 3# ≠R 4# ; n1, n2, n3, n4 are integers between 1 and 500, and make the weight-average molecular weight of the polythiophene derivative be between 3,000 and 100,000.

[0057] The cationic polythiophene derivatives of the structures shown in the above formula (I) and formula (II) have good water solubility and show obvious specificity in detection, and can sensitively detect ClO4 - 、TcO4 - Anion. The conformation and aggregation state of the compounds represented by the above formula (I) and formula (II) in the solution show different states in response to external stimuli, thereby causing changes in their optical properties.

[0058] Second, the present invention provides a visual dual-mode detection of anions (ClO4 - 、TcO4 - ) probe molecules can be used for rapid, quantitative and specific detection of anions; in order to detect ClO4 - 、TcO4 - Purpose of anions;

[0059] The probe molecule of the present invention is used to quickly detect ClO4 - 、TcO4 - Anion Steps:

[0060] (1) Dissolve 5 μmol of probe in 100 mL of ultrapure water to obtain a probe molecule solution;

[0061] (2) adding the probe obtained in step (1) into a cuvette of uniform volume to obtain a detection reagent;

[0062] (3) ClO4 - 、TcO4 - After the standard solution reacts with the reagent obtained in step (2), the changes in its UV-visible absorption spectrum and fluorescence spectrum are measured. The peak change corresponds to ClO4 - 、TcO4 - The linear relationship of concentration values ​​can be used for quantitative analysis;

[0063] (4) Add ClO4 to the detection reagent in step (2) - 、TcO4 - After that, the UV absorption peak of the probe molecule will be red-shifted. - 、TcO4 - As the concentration increases, the peak at 545nm gradually increases, and at the same time, the fluorescence characteristic absorption peak of the probe molecule is quenched and red-shifted, and the overall detection time is less than 10s.

[0064] Preferably, the probe molecule of the present invention can detect ClO4 - 、TcO4 - The concentration range is 0.1-1×10 4The concentration of the probe molecule is in the range of 0.1-100 μM, and more preferably 50 μM.

[0065] Preferably, the reaction conditions include: (1) the volume of the reaction system is 200-3000 μL, and the reaction volume is more preferably 2000 μL; (2) the reaction temperature of the reaction system is 4-40°C, and the reaction temperature is more preferably 25°C; (3) the pH value of the reaction system is 4-14, and more preferably pH=7; (4) the reaction system can detect ClO4 in pure water, organic solvents (methanol, ethanol, acetonitrile), and buffer solutions (HEPES) - 、TcO4 - .

[0066] Third, the present invention provides a method for removing anions (ClO4 - 、TcO4 - ) probe molecules, in order to achieve the removal of ClO4 - 、TcO4 - Purpose of anions;

[0067] The probe molecule of the present invention removes ClO4 - 、TcO4 - Anion Steps:

[0068] (1) dissolving Formula I / Formula II in ultrapure water to obtain a probe molecule solution;

[0069] (2) Add the probe molecule prepared in step (1) to a solution containing ClO4 - 、TcO4 - The reaction was carried out in water;

[0070] (3) After the reaction is completed, the solution is added to the removal system for separation and removal, and the sample after removal is analyzed to obtain the probe molecule to remove ClO4 - 、TcO4 - efficiency;

[0071] Preferably, the removal reaction of the present invention can be separated and removed using different systems:

[0072] (1) Precipitation removal, probe molecules and ClO4 - 、TcO4 - The molar ratio is 0.5:1, 1:1, 1.5:1; preferably ClO4 - 、TcO4 - When the concentration is 0.5-100mM, precipitation can be used for separation and removal;

[0073] (2) Microfiltration removal, the types of filter membranes include but are not limited to: PES, PVDF, PTFE, PC, PP, Nylon66; the pore size of the filter membrane includes but is not limited to 0.2-0.45 μm; preferably ClO4 - 、TcO4 - When the concentration is 5-50 μM, microfiltration can be used for separation and removal;

[0074] (3) Ultrafiltration removal, the pore size of the ultrafiltration system includes but is not limited to: 3-300 kDa; preferably ClO4 - 、TcO4 - When the concentration is 0.1-20 μM, an ultrafiltration system can be used for separation and removal;

[0075] (4) Dialysis removal, the pore size of the dialysis bag includes but is not limited to 8-50 kDa; the material of the dialysis bag includes but is not limited to cellulose ester (CE), regenerated cellulose (RC), PVDF; preferably in ClO4 - 、TcO4 - When the concentration is 2-50μM, a dialysis bag can be used for separation and removal.

[0076] Preparation of probe mother solution: Weigh the solids described in Formula I and Formula II, and use ultrapure water to prepare a mother solution with a concentration of 5 μmol. When testing, use ultrapure water to dilute to a certain concentration for testing.

[0077] Preparation of perchlorate standard solution: Divide the purchased perchlorate standard solution (10 mM) into solutions of equal volumes in small bottles for later use and store in a refrigerator at 4°C.

[0078] Preparation of interfering substances: Prepare the purchased standard solution and powder into a 10 mM solution, divide it into small bottles of equal volume for later use, and store it in a refrigerator at 4°C.

[0079] Synthesis of cationic polythiophene probe molecules

[0080] (1) Synthesis of thiophene monomer: The synthesis of thiophene monomer was carried out according to the synthesis steps in the references (Angew Chem Int Ed. 2002, 41, 1548, J Am Chem Soc. 2003, 125, 4412). The synthesized thiophene monomer was characterized by H NMR. The results are shown below. The numbers correspond to Figure 1 The structural formula in:

[0081] T1: Yield: 80%. 1 H NMR (400MHz, DMSO-d6) δ7.11–7.07 (m, 1H), 6.55 (d, J = 3.2Hz, 1H),

[0082] 4.01(t,J=6.0Hz,2H),3.53–3.45(m,2H),3.11(s,10H),2.19(dq,J=11.8,6.1Hz,2H),2.04(d,J=1.1Hz,3H).

[0083] T2:Yield:50%. 1 H NMR(400MHz,DMSO-d6)δ7.10(dd,J=3.2,1.3Hz,1H),6.54(d,J=3.2Hz,

[0084] 1H),4.02(t,J=5.7Hz,2H),3.34–3.28(m,8H),2.12–2.02(m,5H),1.20(t,J=7.2Hz,9H).

[0085] T3:Yield:14%. 1 H NMR(400MHz,DMSO-d6)δ7.10(dd,J=3.2,1.3Hz,1H),6.53(d,J=3.2Hz,

[0086] 1H),4.01(t,J=5.7Hz,2H),3.39–3.34(m,2H),3.23–3.17(m,6H),2.12(dt,J=11.3,5.7Hz,2H),2.04(d,J=1.1Hz,3H),1.66(dt,J=11.7,7.3Hz,6H),0.91(t,J=7.2Hz,9H).

[0087] T4:Yield:11%. 1 H NMR(400MHz,DMSO-d6)δ7.09(dd,J=3.1,1.3Hz,1H),6.53(d,J=3.2Hz,

[0088] 1H),4.04–3.95(m,2H),3.38(dd,J=7.6,4.3Hz,2H),3.29–3.17(m,7H),2.15–2.06(m,3H),2.04(d,J=1.1Hz,3H),1.61(tt,J=12.2,7.0Hz,8H),1.31(q,J=7.4Hz,8H),0.93(t,J=7.3Hz,11H).

[0089] T5:Yield:10%. 1 H NMR(400MHz,DMSO-d6)δ7.09(d,J=3.1Hz,1H),6.53(d,J=3.3Hz,1H),

[0090] 4.01(t,J=5.5Hz,2H),3.41–3.34(m,2H),3.28–3.13(m,6H),2.09(dt,J=10.7,6.1Hz,2H),2.04(s,3H),1.66–1.55(m,6H),1.29(d,J=3.9Hz,18H),0.90–0.84(m,9H).

[0091] T6:Yield:30%. 1 H NMR(400MHz,DMSO-d6)δ9.29(d,J=1.6Hz,1H),7.85(t,J=1.8Hz,1H),

[0092] 7.75(t,J=1.8Hz,1H),7.06(dt,J=2.3,1.2Hz,1H),6.51(d,J=3.3Hz,1H),4.36(t,J=6.9Hz,2H),3.99(t,J=6.0Hz,2H),3.85(s,3H),2.29(p,J=6.5Hz,2H),1.96(d,J=1.1Hz,3H).

[0093] T7:Yield:40%. 1 H NMR(400MHz,DMSO-d6)δ7.70(d,J=2.1Hz,1H),7.66(d,J=2.1Hz,1H),

[0094] 7.08(dd,J=3.2,1.2 Hz,1H),6.51(d,J=3.2 Hz,1H),4.30(t,J=6.9 Hz,2H),3.97(t,J=6.0 Hz,2H),3.75(s,3H),2.57(s,3H),2.21(t,J=6.4 Hz,2H),1.99(d,J=1.1Hz,3H).

[0095] T8:Yield:60%. 1 H NMR(400 MHz,DMSO-d6)δ7.46–7.44(m,1H),6.79(dd,J=5.3,1.5 Hz,

[0096] 1H),6.63(dd,J=3.1,1.5 Hz,1H),4.05(t,J=5.8 Hz,2H),3.33–3.27(m,8H),1.20(t,J=7.2 Hz,9H).

[0097] T9:Yield:38%.1 H NMR(400 MHz,DMSO-d6)δ6.87(dd,J=3.3,1.4 Hz,1H),6.36(d,J=3.2 Hz,

[0098] 1H),4.46(d,J=5.5 Hz,2H),4.38–4.20(m,2H),3.60(s,9H),2.06(d,J=1.1 Hz,3H).

[0099] T10:Yield:80%. 1 H NMR(400 MHz,DMSO-d6)δ7.07(dd,J=3.2,1.3 Hz,1H),6.50(d,J=3.2

[0100] Hz,1H),3.98(t,J=6.0 Hz,2H),3.43–3.34(m,2H),3.07(s,9H),2.03(d,J=1.1Hz,3H),1.91–1.80(m,2H),1.76(q,J=6.3 Hz,2H).

[0101] T11:Yield:60%. 1 H NMR(400 MHz,DMSO-d6)δ7.05(dd,J=3.3,1.3 Hz,1H),6.46(d,J=3.2

[0102] Hz,1H),3.92(t,J=6.4 Hz,2H),3.31–3.25(m,2H),3.04(s,9H),2.00(d,J=1.2Hz,3H),1.70(dp,J=21.8,6.7 Hz,4H),1.34(dtt,J=27.0,13.7,7.3 Hz,9H).

[0103] T12:Yield:40%. 1 H NMR(400 MHz,DMSO-d6)δ7.05(d,J=3.2 Hz,1H),6.45(d,J=3.2 Hz,

[0104] 1H),3.91(t,J=6.4 Hz,2H),3.30–3.23(m,2H),3.04(s,10H),2.00(s,3H),1.74–1.62(m,4H),1.39(q,J=7.2 Hz,2H),1.35–1.19(m,22H).

[0105] T13:Yield:35%. 1H NMR(400 MHz,DMSO-d6)δ7.13(dd,J=3.3,1.3 Hz,1H),6.63(d,J=3.2

[0106] Hz,1H),4.35(t,J=4.5 Hz,2H),3.78–3.64(m,2H),3.38(q,J=7.2 Hz,6H),2.03(d,J=1.1 Hz,3H),1.23(t,J=7.2 Hz,9H).

[0107] T14:Yield:30%. 1 H NMR(400 MHz,DMSO-d6)δ7.75–7.57(m,2H),7.08(dd,J=3.3,1.3 Hz,

[0108] 1H),6.55(d,J=3.2 Hz,1H),4.59(t,J=4.9 Hz,2H),4.24(t,J=4.9 Hz,2H),3.78(s,3H),2.65(s,3H),1.98(d,J=1.1 Hz,3H).

[0109] T15:Yield:20%. 1 H NMR(400 MHz,DMSO-d6)δ9.25(d,J=2.0 Hz,1H),7.82(d,J=1.9 Hz,

[0110] 1H),7.75(d,J=1.9 Hz,1H),7.07(dd,J=3.2,1.4 Hz,1H),6.60(d,J=3.2 Hz,1H),4.62(t,J=4.9 Hz,2H),4.29(t,J=4.9 Hz,2H),3.89(s,3H),1.98(d,J=1.1 Hz,3H).

[0111] T16:Yield:50%. 1 H NMR(400 MHz,DMSO-d6)δ7.71(d,J=2.1 Hz,1H),7.65(d,J=2.1 Hz,

[0112] 1H),7.06(dt,J=2.1,1.1 Hz,1H),6.49(d,J=3.2 Hz,1H),4.20(t,J=7.2 Hz,2H),3.96(t,J=6.2 Hz,2H),3.75(s,3H),2.60(s,3H),2.00(d,J=1.2 Hz,3H),1.94–1.81(m,2H),1.74(dt,J=9.6,6.2 Hz,2H).

[0113] T17:Yield:60%. 1 H NMR(400 MHz,DMSO-d6)δ9.24(d,J=1.7 Hz,1H),7.84(t,J=1.9 Hz,1H),

[0114] 7.75(t,J=1.8Hz,1H),7.07(dd,J=3.2,1.3Hz,1H),6.49(d,J=3.2Hz,1H),4.27(t,J=7.1Hz,2H),3.97(t,J=6.3Hz,2H),3.87(s,3H),2.01(d,J=1.1Hz,3H),2.00–1.90(m,2H),1.80–1.65(m,2H).

[0115] T18:Yield:52%. 1 H NMR(400MHz,DMSO-d6)δ7.07(dd,J=3.4,1.2Hz,1H),6.51(d,J=3.2

[0116] Hz,1H),4.07–3.90(m,2H),3.31–3.19(m,8H),2.02(d,J=1.1Hz,3H),1.77(dp,J=13.0,6.0Hz,4H),1.17(tt,J=7.3,1.8Hz,9H).

[0117] (2) Synthesis of cationic polythiophene polymers, refer to (Angew Chem Int Ed. 2002, 41, 1548, J Am Chem Soc. 2003, 125, 4412) for polymerization: thiophene monomer (0.5 g, 2 mmol) was dissolved in 15 mL of chloroform solution, and then the monomer solution was added dropwise to a nitrogen-protected ferric chloride (1.0 g, 6 mmol) chloroform (25 mL) solution. The mixture was magnetically stirred at room temperature for 48 hours. The reaction mixture was evaporated to dryness to obtain a crude product, which was washed with methanol. After washing, the crude product was dissolved in acetone, and an excess of tetrabutylammonium chloride was added to precipitate the product. After precipitation, the product was dissolved in methanol, and hydrazine hydrate was added for dedoping. The product solution was evaporated, and after completion, the obtained product was washed several times with a saturated tetrabutylammonium chloride acetone solution. After washing, Soxhlet extraction was performed with acetone, and then reduced pressure drying was performed to obtain the final polymer. The remaining polymers are polymerized according to similar steps. The copolymerized thiophene is obtained by mixing different monomers in a certain ratio and then polymerizing them according to the above steps.

[0118] Absorption and fluorescence spectra responses of various cationic polythiophene probes to perchlorate

[0119] The prepared probe molecules with different structures (Formula I and Formula II) were added into a colorimetric cell with uniform volume to obtain the detection of ClO4 - Detection reagents;

[0120] ClO4 - The standard solution is added into the colorimetric cell to measure the changes in UV-visible absorption spectrum, fluorescence spectrum, visual color and fluorescence color;

[0121] like Figure 2 As shown, in the molecule of the regulating formula (I), R 1 After substituent structure, probe molecule is ClO4 - There is also an obvious signal output response, which is specifically manifested as: the wavelength of the UV-visible absorption spectrum is red-shifted and the color changes, and the fluorescence spectrum is quenched and accompanied by the change of fluorescence color, indicating that the synthesized probe molecule (Formula I) 4-position R of thiophene 1 When the structure is CH3 or H, it can be used for ClO4 - Absorption / fluorescence dual-mode detection.

[0122] like Figure 3 As shown, after adjusting the length of the carbon chain m in the molecule of formula (I), the probe molecules are all responsive to ClO4 - There is a good signal output response, indicating that the synthesized probe molecule (Formula I) with a carbon chain length of 1-15 can be used for ClO4 - Absorption / fluorescence dual-mode detection.

[0123] like Figure 4 As shown, in the molecule of the regulating formula (I), R # After the structure of the substituent, the probe molecules are all ClO4 - There is a good signal output response, indicating that the synthesized probe molecule (Formula I) R # Substituents are quaternary ammonium salt substituents (methyl, ethyl, propyl, butyl, hexyl), 1-methylimidazole, 1,2-dimethylimidazole structures can all be used for ClO4 - Absorption / fluorescence dual-mode detection.

[0124] like Figure 5 As shown in the figure, after changing different solvents, the probe molecules all reacted with ClO4 - There is a good signal output response, indicating that the synthesized probe molecule (Formula I) can be used for ClO4 in methanol / water (40:60, V / V), ethanol / water (40:60, V / V), acetonitrile / water (20:80, V / V), and HEPES buffer. - Absorption / fluorescence dual-mode detection.

[0125] like Figure 6 As shown, after adjusting the structure and polymerization ratio of the monomers in the molecule of formula (II), the probe molecules are all responsive to ClO4 - There is a good signal output response, indicating that the synthesized probe molecule (Formula II) can be used for ClO4 after adjusting the structure and polymerization ratio of the monomer. - Absorption / fluorescence dual-mode detection.

[0126] Colorimetric and absorption spectral sensing for perchlorate anion detection

[0127] 1. Quantitative detection of perchlorate by UV-visible absorption spectroscopy

[0128] The probe mother solution was dissolved in ultrapure water to obtain a probe molecule solution. 2 mL of the obtained probe molecule solution was added to a colorimetric cell of uniform volume as a detection - Reagents;

[0129] Scan the UV-visible absorption spectrum of the probe molecule, and then gradually add a certain concentration of ClO4 into the colorimetric cell. - The standard solution was mixed evenly and its UV-visible absorption spectra were measured respectively, and the peak values ​​at 410nm and 545nm were read;

[0130] The results are as follows Figure 7 show, Figure 7 A indicates that the absorbance of the aforementioned probe molecule at 410 nm increases with the increase of ClO4 - The absorbance at 545 nm gradually increased with the addition of . Figure 7 B shows the absorbance ratio and ClO4 -The relationship between the concentration change and the ClO4 - As the concentration increases, the absorbance ratio A 545nm / A 410nm Gradually increasing, quantitative detection can be achieved between 2-10μM with good linear relationship (R 2 =0.99612). According to the calculation method of detection limit, the probe molecule has a good affinity for ClO4 - The detection line is 1.46μmol / L.

[0131] 2. Visual detection of perchlorate by probe molecule

[0132] The probe mother solution was dissolved in ultrapure water to obtain a probe molecule solution. 1 mL of the obtained probe molecule solution was added to a glass vial as a ClO4 detection - Reagents;

[0133] Different concentrations of ClO4 - Add the standard solution to the vial, mix well and take photos under natural light indoors ( Figure 7 C) Use Color Grab software to extract the RGB value of each vial ( Figure 7 D)

[0134] Figure 7 C, D results show that with the ClO4 - As the concentration of the probe molecule increases, the solution color changes from yellow to purple. The visible detection limit is 3 μmol / L. The B value / (R+G) value obtained by the software is consistent with the ClO4 - There is a linear relationship between the concentrations of 2 It is 0.9947, and the detection limit is 1μmol / L.

[0135] 3. Measures to improve the sensitivity of colorimetric sensing for perchlorate detection

[0136] To meet the actual detection needs, the following methods can be used to improve the detection of ClO4 by UV-visible absorption spectroscopy: - Sensitivity;

[0137] (1) Dissolve the probe mother solution in ultrapure water to obtain a probe molecule solution, and mix the probe molecule solution with trace amounts of ClO4 - The solution was added to an ultrafiltration tube and centrifuged at 5000 g for 10 min. The upper retentate was taken for UV-visible absorption spectrum detection, and the peaks at 410 nm and 545 nm were read.

[0138] The results are as follows Figure 7 As shown in E, the probe molecule is concentrated by ultrafiltration to ClO4 -The detection limit can reach 0.1μmol / L (10ppb), which is lower than the ClO4 in the national standard (GB 5749-2022 Drinking Water Hygiene Standard) - The limit standard of 0.7μmol / L (70ppb) can meet the actual requirements of ClO4 - Testing needs;

[0139] (2) Containing ClO4 - The water sample was evaporated and pre-concentrated, and after evaporation, 2 mL of water was used for re-dissolution. The probe molecule solution was added to the water sample for UV-visible absorption spectrum detection, and the peaks at 410 nm and 545 nm were read;

[0140] The results are as follows Figure 7 As shown in F, it shows that the probe molecule reacts with ClO4 after evaporation and concentration. - The detection limit can reach 0.1μmol / L (10ppb), which is lower than the ClO4 in the national standard (GB 5749-2022 Drinking Water Hygiene Standard) - The limit standard of 0.7μmol / L (70ppb) can meet the actual requirements of ClO4 - testing needs.

[0141] 4. Probe molecule selectivity for anions

[0142] Common anions in water include (Cl - 、NO2 - IO3 - 、F - 、HCO3 - 、CO3 2- 、HPO4 2- 、H2PO4 - 、NO3 - BrO3 - 、ClO2 - 、ClO3 - 、SO4 2- 、P2O7 4- 、SCN - ,I - ) as the detection anion (ClO4 - 、ReO4 - / TcO4 - ) interfering substances in the process;

[0143] In order to more intuitively observe the effect of the interaction between the probe molecule and the anion, the color change of the solution was observed under a fluorescent lamp and photographed with a camera;

[0144] like Figure 8As shown in A, when the interfering substance is added to the probe molecule, the color of the solution does not change, but when ClO4 - 、ReO4 - / TcO4 - After addition, the color of the solution changed to purple.

[0145] The probe mother solution was dissolved in ultrapure water to obtain a probe molecule solution. 2 mL of the obtained probe molecule solution was added to a colorimetric cell of uniform volume as a reagent for detecting anions. Under the same conditions, a UV-visible absorption spectrum was scanned, and the absorbance value at 545 nm was compared with the absorbance value at 410 nm. 545nm / A 410nm As a parameter to measure the response of the probe molecule to the substance to be tested;

[0146] The results are as follows Figure 8 As shown in B, in addition to ClO4 - 、ReO4 - / TcO4 - A of other anions 545nm / A 410nm Ratio <0.2, while ClO4 - 、ReO4 - / TcO4 - A 545nm / A 410nm The ratio > 1 indicates that the probe molecule detects ClO4 using UV-visible absorption spectroscopy. - 、ReO4 - / TcO4 - It has good selectivity;

[0147] In actual detection, high concentrations of iodine ions and hydrogen sulfide may affect the probe molecule's sensitivity to ClO4 - 、ReO4 - / TcO4 - If the response is small, silver nitrate or solid phase extraction (Ag) columns can be used to eliminate interference and achieve better detection results.

[0148] Fluorescence colorimetry and fluorescence spectroscopy for the detection of perchlorate anions

[0149] 1. Detection of perchlorate by fluorescence spectroscopy

[0150] The probe mother solution was dissolved in ultrapure water to obtain a probe molecule solution. 2 mL of the obtained probe molecule solution was added to a uniform volume fluorescence cell as a detection ClO4 - Reagents;

[0151] The fluorescence spectrum of the probe molecule was measured, and the fluorescence intensity at a wavelength of 540 nm was recorded as I0. Subsequently, a certain concentration of ClO4 was gradually added to the fluorescence pool.- The standard solution was mixed evenly and the corresponding fluorescence spectrum was measured, and the fluorescence intensity at a wavelength of 540 nm was recorded as I;

[0152] The results are as follows Fig. 9 As shown, Fig. 9 A indicates that the probe molecule is excited at an excitation wavelength of 420 nm, has a maximum absorption peak at 540 nm, and emits strong yellow fluorescence in aqueous solution. - With the addition of , the fluorescence intensity of the probe molecule gradually decreased, and the maximum fluorescence absorption peak red-shifted. Fig. 9 B shows that the maximum absorption peak is red-shifted and ClO4 - The relationship between the concentration of ClO4 - The increase of concentration, FI 620nm / FI 540nm The fluorescence intensity ratio gradually increased. Fig. 9 C shows that the fluorescence quenching rate at 540 nm is similar to that of ClO4 - The relationship between the concentration of ClO4 - As the concentration increases, the fluorescence intensity at 540nm gradually decreases. - When the concentration of 0.1 mM was added dropwise, the quenching rate reached 86.7%. According to the calculation method of the detection limit, the probe molecule has a strong affinity for ClO4 - The detection limit is 9×10 -8 mol / L.

[0153] 2. Probe molecule selectivity for anions

[0154] In order to observe the probe molecule and ClO4 more intuitively - 、ReO4 - / TcO4 - The effect of the interaction between the probe molecule and other interfering substances is shown in the figure. The effect of the probe molecule on the anion (ClO4 - 、ReO4 - / TcO4 - ) during the selective investigation of the solution fluorescence;

[0155] like Fig.10 As shown in A, when the interfering substance is added to the probe molecule, the fluorescence color does not change, but when ClO4 is added - 、ReO4 - / TcO4 - After that, the fluorescence color turns purple-red and a certain degree of quenching occurs;

[0156] The probe mother solution was dissolved in ultrapure water to obtain a probe molecule solution. 2 mL of the obtained probe molecule solution was added to a fluorescent cell of uniform volume as the detection anion (ClO4 - 、ReO4 - / TcO4 - ) reagents;

[0157] Under the same conditions, the fluorescence spectrum was scanned, and the ratio of the fluorescence intensity value at 540nm to the fluorescence intensity value at 620nm was used as a parameter to measure the response degree of the probe molecule to the substance to be tested; the results are as follows Fig.10 As shown in B, Fig.10 B is the probe molecule's response to ClO4 at different excitation wavelengths - 、ReO4 - / TcO4 - The results show that ClO4 can be detected at different excitation wavelengths. - 、ReO4 - / TcO4 - Perform specific testing.

[0158] Cationic polythiophene probe molecules for removal of perchlorate

[0159] The individual probe molecules were mixed with the added ClO4 - The probe molecules were then scanned by transmission electron microscopy, and the results were as follows: Fig.11 As shown in A, at the same magnification, the probe molecule itself has a smaller particle size, but when ClO4 is added - Afterwards, the probe molecules will aggregate to form a large-size group;

[0160] The probe molecule solution was added to the colorimetric cell for dynamic light scattering experiment. After the scanning was completed, ClO4 - Add to the colorimetric cell, mix well, and scan again; the result is as follows: Fig.11 As shown in B, after adding ClO4 - The average hydration radius of the probe molecule increased from 255 nm to 1110 nm, indicating that the addition of ClO4 - The molecular structure of the probe then changes, favoring an aggregated state;

[0161] For high concentrations of ClO4 - Contaminated water samples can be removed by precipitation, adding ClO4 - (5mM) probe molecule with a stoichiometric ratio of 1:1.5, due to ClO4 - The schematic diagram of the effect of causing probe molecules to aggregate and precipitate to be removed is shown in Fig.11 As shown in C, it can be seen that ClO4 -The addition of will change the structure of the probe molecule, and precipitation will occur when it is left standing, and the precipitation is visible to the naked eye. After the precipitation is left for 30 minutes, centrifuge and take the supernatant. After diluting the supernatant 100 times, add the probe molecule again to scan the UV-visible absorption spectrum, read the absorbance value at 545nm and the absorbance value at 410nm as the ratio, which is used as an important parameter to measure the removal effect;

[0162] The results are as follows Fig.11 As shown in D, with the increase of probe molecule concentration, ClO4 - The content of ClO4 decreased significantly, and the absorbance ratio was used to measure the probe molecule's - The removal rate reached 84.58%, and ClO4 was removed by precipitation. - The range is 0.5-100mM;

[0163] The probe molecules were added to the ClO4 - The solution was shaken for 5 min, sucked into a needle filter, and microfiltration was performed using a 0.22 μm PES membrane. The probe molecule was added to the filtrate again for UV-visible absorption spectrum scanning. The flow chart is shown in the figure. Fig.11 As shown in E, the absorbance value at 545nm is read and the ratio of the absorbance value at 410nm is taken as an important parameter to measure the removal effect;

[0164] The results are as follows Fig.11 As shown in F, after filtration with a membrane, the probe molecule and ClO4 - The formed complex is effectively retained on the microporous filter membrane, resulting in ClO4 - Concentration reduction enables rapid on-site removal of ClO4 - As the amount of probe molecules increases, a removal rate of 91.68% can be achieved, and ClO4 is removed by membrane filtration. - The range is 5-50μM;

[0165] The probe molecule is mixed with a trace amount of ClO4 - (1 μM) was mixed and added to the ultrafiltration tube, and ultrafiltration was centrifuged at 5000 g for 10 min. The permeate layer was taken out and evaporated and concentrated to 2 mL. After concentration, the probe molecule was added again for UV-visible absorption spectrum scanning. The operation flow chart is shown in the figure. Fig.11 As shown in G, the absorbance value at 545nm is read and the ratio of the absorbance value at 410nm is taken as an important parameter to measure the removal effect;

[0166] The results are as follows Fig.11 As shown in H, after adding the probe solution (PT), ClO4 in the permeate - The absorbance ratio decreased significantly, and this method can be used to detect low concentration ClO4 in water. -Effective removal of ClO4 by ultrafiltration - The range was 0.1-10 μM, and the removal rate was 98.43%.

[0167] 200 μM probe molecules were loaded into an 8 kDa dialysis bag and placed in 200 mL of ClO4 - (20 μM) solution, magnetic stirring for 12 h. The schematic diagram of the process is shown in Fig.11 As shown in Figure 1, the absorbance value at 545nm is read and the ratio of the absorbance value at 410nm is taken as a measure of the binding of the probe molecule to ClO4 - Important parameters of the effect;

[0168] like Fig.11 As shown in J, due to the semi-permeable membrane properties of the dialysis bag, ClO4 - Diffusion can occur inside and outside the dialysis bag. When the dialysis bag containing the probe molecule is immersed in a solution containing ClO4 - When in solution, ClO4 - The probe molecules diffuse into the dialysis bag and form complexes with the probe molecules in the bag, which causes the color of the probe molecules in the bag to change and the absorbance ratio to increase significantly. - The removal rate gradually increases, and it can remove large amounts of ClO4 - Achieved removal, removal rate 42.54%, dialysis removal of ClO4 - The concentration range is 2-50 μM.

[0169] Cationic polythiophene probe molecule recovery

[0170] In order to save resources and recycle them, the cationic polythiophene probe molecules are recycled;

[0171] Cationic polythiophene probe molecules were reacted with ClO4 - After the binding is completed, add NaCl (10mM) solution or heat treatment, shake for 5 minutes, and after the shaking is completed, place the solution in an ultrafiltration tube for ultrafiltration, 14000rpm, centrifuge for 10 minutes. The probe molecule will be retained in the ultrafiltration retentate due to its molecular weight. Use the retentate to add ClO4 again - UV-visible absorption spectroscopy can be used to determine the recycling effect of the probe molecules. The principle diagram is shown in the figure. Fig.12 As shown in A; after the detection is completed, NaCl (10mM) solution is added again and the above steps are repeated four times. The absorbance value at 545nm is read and the ratio of the absorbance value at 410nm is taken as an important parameter to measure the recovery effect of the probe molecule; since high concentration of salt solution or heating will destroy ClO4 - In the binding state of the probe molecule, ultrafiltration can be used to separate small-particle ClO4- , Cl - Separate from the probe molecule to recover the probe molecule. Fig.12 B The results show that the probe molecule still maintains its affinity to ClO4 even after four cycles. - Good detection performance, with a reuse rate of 97.28%.

[0172] Cationic polythiophene probe molecule for detection of pertechnetate / perrhenate

[0173] The probe mother solution was dissolved in ultrapure water to obtain a probe molecule solution. 2 mL of the obtained probe molecule solution was added to a colorimetric cell of uniform volume as a detection reagent for ReO4 - 、TcO4 - Reagents;

[0174] Scan the UV-visible absorption spectrum of the probe molecule, and then gradually add a certain concentration of ReO4 into the colorimetric cell. - 、TcO4 - The solution was mixed evenly and its UV-visible absorption spectra were measured respectively, and the peaks at 410nm and 545nm were read;

[0175] The results are as follows Fig.13 As shown, Fig.13 The absorbance of the aforementioned probe molecule at 410 nm increases with the increase of TcO4 - The addition of gradually decreased, while the absorbance at 545nm gradually increased, indicating that the synthesized probe molecule can - Conduct sensitive testing;

[0176] Fig.13 The absorbance of the aforementioned probe molecule at 410 nm increases with the increase of ReO4 - The addition of gradually decreased, while the absorbance at 545nm gradually increased, indicating that the synthesized probe molecule can be used for ReO4 - Conduct sensitive testing;

[0177] Since all Tc isotopes are radioactive, it is difficult to directly 99 However, since Tc(VII) and Re(VII) have similar physical and chemical properties, including the same ionic form and radius, they are usually oxidized in the form of perrhenate (ReO4 - ) as 99 TcO4 - In this experiment, the probe molecule can react with ReO4 - 、TcO4 - Sensing detection is performed, and the probe molecule is sensitive to ReO4 - With TcO4 -The response is similar, so ReO4 can be used in the experiment - Replacement of TcO4 - Conduct experiments.

[0178] The probe detects ReO4 - / TcO4 - The selectivity of the anion in the process has been shown in Example 3 ( Figure 8 )、Example 4( Fig.10 ) is described in detail and will not be repeated here.

[0179] Cationic polythiophene probe molecules for removal of pertechnetate

[0180] For high concentrations of ReO4 - / TcO4 - Contaminated water samples can be removed by precipitation. Different concentrations of probe molecules are added. Due to ReO4 - / TcO4 - The probe molecules are caused to aggregate, and the supernatant is centrifuged after standing for 30 minutes. The supernatant is diluted 100 times and the probe molecules are added again for UV-visible absorption spectrum scanning. The absorbance value at 545nm is read as the ratio of the absorbance value at 410nm, which is used as an important parameter to measure the removal effect. The principle diagram is shown in Example 5 above.

[0181] The results are as follows Fig.14 As shown in A, as the concentration of probe molecules increases, ReO4 - / TcO4 - The content of ReO4 decreased significantly, and the absorbance ratio was used to measure the probe molecule's - / TcO4 - The removal rate is 94.21%, and ReO4 is removed by precipitation - / TcO4 - The range is 0.5-100mM;

[0182] The probe molecules were added to the - / TcO4 - The solution was shaken for 5 minutes, sucked into a needle filter, and microfiltration was performed using a 0.22μm nylon membrane. The probe molecule was added to the filtrate again for UV-visible absorption spectrum scanning. The absorbance value at 545nm was read and the ratio of the absorbance value at 410nm was taken as an important parameter to measure the removal effect.

[0183] The results are as follows Fig.14 As shown in Figure B, after filtration with the membrane, the complex formed by the probe molecule and the anion is effectively retained on the microporous membrane, resulting in a significant decrease in the absorbance ratio of the anion in the filtrate, indicating that this method can be used for rapid on-site detection of ReO4 - / TcO4 - Remove ReO4 by membrane filtration - / TcO4 - The range is 5-50μM for ReO4 - / TcO4 - The removal rate is 81.01%;

[0184] The probe molecules were mixed with 10 μM ReO4 - / TcO4 - Mix well and add to the ultrafiltration tube, centrifuge at 5000g for 10 minutes, take out the permeate layer and add the probe molecule again for UV-visible absorption spectrum scanning, read the absorbance value at 545nm and the absorbance value at 410nm as the ratio, which is an important parameter to measure the removal effect;

[0185] The results are as follows Fig.14 As shown in C, after adding the probe solution (PT), ReO4 in the permeate - / TcO4 - The absorbance ratio of the water was significantly reduced. This method can be used to detect low concentration ReO4 - / TcO4 - Effective removal of ReO4 by ultrafiltration - / TcO4 - The range is 1-20μM for ReO4 - / TcO4 - The removal rate is 94.21%;

[0186] 200 μM probe molecules were loaded into an 8 kDa dialysis bag and placed in 200 mL of ReO4 - / TcO4 - (20 μM) solution, magnetically stirred for 12 h, and the absorbance at 545 nm was read and compared with the absorbance at 410 nm to measure the binding of the probe molecule to ReO4 - / TcO4 - Important parameters of the effect;

[0187] like Fig.14 As shown in D, as the amount of probe molecules increases, the - / TcO4 - The removal rate gradually increases, and it can remove large amounts of ReO4 - / TcO4 - The solution was removed, with a removal rate of 61.0%, and ReO4 was removed by dialysis - / TcO4 - The concentration range is 2-50 μM;

[0188] The above examples show that the polythiophene derivatives developed by the present invention have the characteristics of high sensitivity and good stability, and can be used as adsorbents to remove anions, and can be used as a simple and fast method for anion (ClO4 - 、TcO4 - ) simultaneously detected and removed.

[0189] Matters not covered by the present invention are known technologies.

[0190] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A cationic polythiophene derivative for detecting and removing perchlorate and pertechnetate, characterized in that : The structure is shown in formula (I) and formula (II): Formula (I) is a homopolymer structure, R1 is H or CH3; R2 is O or CH2; R3 is an alkyl group with an integer of carbon number between 1 and 6 and its isomers: methyl, ethyl, propyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, isohexyl; R4 is H or CH3; m is an integer between 0 and 15; M is Cl or Br; n is a positive integer, and the weight average molecular weight of the polythiophene derivative is 3,000 to 50,000; Formula (II) consists of thiophene units connected at the 2 and 5 positions to form a conjugated main chain, and its structural formula is shown below: Formula (II) is a copolymer structure, R1 is H or CH3; R2 is O or CH2; m is an integer between 0 and 15; M is Cl or Br; R 1# ,R 2# ,R 3# ,R 4# , selected from R in the above formula (I) # Substituents, wherein R3 is an alkyl group with an integer carbon number between 1 and 6 and its isomers: methyl, ethyl, propyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, isohexyl; R4 is H or CH3; and satisfies R 1# ≠R 2# ≠R 3# ≠R 4# ; n1, n2, n3, n4 are integers between 1 and 500, and make the weight-average molecular weight of the polythiophene derivative be between 3,000 and 100,000.

2. A method for detecting perchlorate and pertechnetate using the cationic polythiophene derivative according to claim 1, characterized in that: The following steps are involved: (1) dissolving 5 μmol of formula (I) and formula (II) in 100 mL of ultrapure water to obtain a probe molecule solution; (2) adding the probe obtained in step (1) into a cuvette of uniform volume to obtain a detection reagent; (3) ClO4 - 、TcO4 - After the standard solution reacts with the reagent obtained in step (2), the changes in its UV-visible absorption spectrum and fluorescence spectrum are measured. The peak changes correspond to the ClO4 - 、TcO4 - Quantitative analysis of the linear relationship between concentration values; (4) Add ClO4 to the detection reagent in step (2) - 、TcO4 - After that, the UV absorption peak of the probe molecule will be red-shifted. - 、TcO4 - As the concentration increases, the peak at 545nm gradually increases, and at the same time, the fluorescence characteristic absorption peak of the probe molecule is quenched and red-shifted, and the overall detection time is less than 10s.

3. The method for detecting perchlorate and pertechnetate using a cationic polythiophene derivative according to claim 2, characterized in that: This method can detect ClO4 - 、TcO4 - The concentration range is 0.1-1×10 4 The concentration of the probe molecule solution ranged from 0.1 to 100 μM.

4. The method for detecting perchlorate and pertechnetate using a cationic polythiophene derivative according to claim 2, characterized in that: The volume of the detection reaction system is 200-3000 μL; the reaction temperature is 4-40° C.; the pH value of the reaction system is 4-14; the detection reaction is carried out in pure water, organic solvents: methanol, ethanol, acetonitrile, and buffer solution HEPES.

5. A method for removing perchlorate and pertechnetate using the cationic polythiophene derivative according to claim 1, characterized in that: The following steps are involved: (1) dissolving the compound of formula (I) / formula (II) in ultrapure water to obtain a probe molecule solution; (2) Add the probe molecule prepared in step (1) to a solution containing ClO4 - 、TcO4 - The reaction was carried out in water; (3) After the reaction is completed, the solution is added to the removal system for separation and removal, and the sample after removal is analyzed to obtain the probe molecule to remove ClO4 - 、TcO4 - efficiency.

6. The method for removing perchlorate and pertechnetate using a cationic polythiophene derivative according to claim 5, characterized in that: ClO4 - 、TcO4 - When the concentration is 0.5-100mM, the probe molecule is separated and removed by precipitation. - 、TcO4 - The molar ratios are 0.5:1, 1:1, and 1.5:

1.

7. The method for removing perchlorate and pertechnetate using a cationic polythiophene derivative according to claim 5, characterized in that: ClO4 - 、TcO4 - When the concentration is 5-50 μM, microfiltration is used for separation and removal. The types of filter membranes include but are not limited to: PES, PVDF, PTFE, PC, PP, Nylon66; the pore size of the filter membrane includes but is not limited to 0.2-0.45 μm.

8. The method for removing perchlorate and pertechnetate using a cationic polythiophene derivative according to claim 5, characterized in that: ClO4 - 、TcO4 - When the concentration is 0.1-20 μM, an ultrafiltration system is used for separation and removal, and the pore size of the ultrafiltration system includes but is not limited to: 3-300 kDa.

9. The method for removing perchlorate and pertechnetate using a cationic polythiophene derivative according to claim 5, characterized in that: ClO4 - 、TcO4 - When the concentration is 2-50 μM, a dialysis bag is used for separation and removal, and the pore size of the dialysis bag includes but is not limited to 8-50 kDa; the material of the dialysis bag includes but is not limited to cellulose ester CE, regenerated cellulose RC, and PVDF.

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