CN111088032A - Preparation method of fluorescent polymer for simultaneously detecting trivalent chromium ions and hexavalent chromium ions - Google Patents
Preparation method of fluorescent polymer for simultaneously detecting trivalent chromium ions and hexavalent chromium ions Download PDFInfo
- Publication number
- CN111088032A CN111088032A CN201911279324.2A CN201911279324A CN111088032A CN 111088032 A CN111088032 A CN 111088032A CN 201911279324 A CN201911279324 A CN 201911279324A CN 111088032 A CN111088032 A CN 111088032A
- Authority
- CN
- China
- Prior art keywords
- chromium ions
- hexavalent chromium
- blue
- fluorescent
- solution
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
- C09K11/02—Use of particular materials as binders, particle coatings or suspension media therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y20/00—Nanooptics, e.g. quantum optics or photonic crystals
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
- C09K11/02—Use of particular materials as binders, particle coatings or suspension media therefor
- C09K11/025—Use of particular materials as binders, particle coatings or suspension media therefor non-luminescent particle coatings or suspension media
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
- C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
- C09K11/65—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing carbon
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/64—Fluorescence; Phosphorescence
- G01N21/6428—Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes"
- G01N21/643—Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes" non-biological material
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
- G01N21/63—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light optically excited
- G01N21/64—Fluorescence; Phosphorescence
- G01N21/6428—Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes"
- G01N2021/6432—Quenching
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A20/00—Water conservation; Efficient water supply; Efficient water use
- Y02A20/20—Controlling water pollution; Waste water treatment
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Physics & Mathematics (AREA)
- Nanotechnology (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Organic Chemistry (AREA)
- Optics & Photonics (AREA)
- Immunology (AREA)
- General Physics & Mathematics (AREA)
- Crystallography & Structural Chemistry (AREA)
- Composite Materials (AREA)
- Molecular Biology (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Inorganic Chemistry (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Pathology (AREA)
- Biophysics (AREA)
- Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
The invention discloses a preparation method of a fluorescent polymer for simultaneously detecting trivalent chromium ions and hexavalent chromium ions, which comprises the following steps: (1) preparing a blue carbon dot and a red carbon dot, wherein the excitation wavelength of the blue carbon dot is about 370nm, the emission wavelength is about 450nm, the excitation spectrum of the blue carbon dot is completely overlapped with the absorption spectrum of hexavalent chromium ions, and the excitation spectrum and the absorption spectrum of the hexavalent chromium ions are quenched by the hexavalent chromium ions through an internal filtering effect; the excitation wavelength of the red carbon dot is about 570nm, the emission wavelength is about 600nm, and the red carbon dot can be quenched by trivalent chromium ions based on electron transfer; (2) coating blue carbon dots inside the silicon spheres; (3) and coating a fluorescent imprinting layer of trivalent chromium ions on the surface of the silicon ball coated with the blue carbon dots to finally form the fluorescent polymer with the core-shell structure, wherein the fluorescent imprinting layer is doped with the red carbon dots and is of a mesoporous structure. The fluorescent polymer obtained by the method can be used for simultaneously detecting trivalent chromium ions and hexavalent chromium ions.
Description
Technical Field
The invention belongs to the technical field of detection methods, and particularly relates to a preparation method of a fluorescent polymer for simultaneously detecting trivalent chromium ions and hexavalent chromium ions.
Background
Metal ions exist in the environment in a plurality of ionic forms, and the ionic toxicity of different forms is different. Therefore, for the detection of metal ions in the environment, it is important to detect ions of each form separately in addition to the total amount of ions. Among the detection methods of a plurality of metal ions, the fluorescence detection method has the advantages of no need of expensive instruments, no need of complex sample pretreatment process, simple operation, high speed of the detection process and the like, and is widely applied.
At present, documents about fluorescence detection of chromium ions generally only detect ions of a certain form, such as hexavalent chromium detection or trivalent chromium detection, and few documents report that a fluorescence method simultaneously detects chromium ions of two forms. Even if documents report that hexavalent chromium and trivalent chromium can be detected simultaneously, the common method is to reduce hexavalent chromium to trivalent chromium for detection, or oxidize trivalent chromium to hexavalent chromium by potassium permanganate or hydrogen peroxide, and two real chromium ion forms are not detected simultaneously.
Disclosure of Invention
The first object of the present invention is to solve the above problems and to provide a method for preparing a fluorescent polymer for simultaneously detecting trivalent chromium ions and hexavalent chromium ions.
It is a second object of the present invention to provide a fluorescent polymer obtainable by the above process.
It is a third object of the present invention to provide the use of the above fluorescent polymers.
The purpose of the invention is realized by the following technical scheme:
a method for preparing a fluorescent polymer for simultaneously detecting trivalent chromium ions and hexavalent chromium ions, the method comprising the steps of:
(1) preparing a blue carbon dot and a red carbon dot, wherein the excitation wavelength of the blue carbon dot is about 370nm, the emission wavelength is about 450nm, the excitation spectrum of the blue carbon dot is completely overlapped with the absorption spectrum of hexavalent chromium ions, and the excitation spectrum and the absorption spectrum of the hexavalent chromium ions are quenched by the hexavalent chromium ions through an internal filtering effect; the excitation wavelength of the red carbon dot is about 570nm, the emission wavelength is about 600nm, and the red carbon dot can be quenched by trivalent chromium ions based on electron transfer;
(2) coating blue carbon dots inside the silicon spheres;
(3) and coating a fluorescent imprinting layer of trivalent chromium ions on the surface of the silicon ball coated with the blue carbon dots to finally form the fluorescent polymer with the core-shell structure, wherein the fluorescent imprinting layer is doped with the red carbon dots and is of a mesoporous structure.
Further, in the step (1), the preparation method of the blue carbon dots comprises the following steps: dissolving 1.2g of citric acid and 2.1mL of ethylenediamine in 80mL of water, placing the solution in a hydrothermal reaction kettle, reacting in an oven at 180 ℃ for 8 hours, taking out the solution, and dialyzing the solution to remove unreacted micromolecules to obtain a light yellow blue carbon dot solution;
the preparation method of the red carbon dots comprises the following steps: dissolving 2.8g of citric acid in 50mL of formamide, placing the formamide in a hydrothermal reaction kettle, reacting in an oven at 180 ℃ for 8 hours, taking out the formamide, filtering large particles by using a 0.22-micron microporous filter membrane, dialyzing to remove small molecules, precipitating acetone to obtain solid carbon dots, and then re-dispersing the solid carbon dots in 50mL of water to obtain a brownish red carbon dot solution.
Furthermore, in the step (2), the blue carbon dots are coated inside the silicon spheres by a reverse microemulsion method, and the specific method comprises the following steps: dispersing 1.8mL of triton-100 and 1.8mL of n-hexanol in 7.5mL of cyclohexane, then adding 500 μ L of the blue carbon dot solution obtained in the step (1), adding 60 μ L of ammonia water with the concentration of 28 wt%, fully stirring to form microemulsion, adding 500 μ L of ethyl orthosilicate, stirring and reacting for 10 hours at room temperature, adding acetone into the reaction liquid after the reaction is finished, demulsifying to obtain white flocculent precipitate, collecting the white flocculent precipitate, washing with ethanol and water for three times respectively, and drying in vacuum for later use.
Still further, in the step (3), the method for coating the trivalent chromium ion fluorescent imprinted layer on the surface of the silicon sphere comprises the following steps: dispersing 10mg of the blue carbon dot-coated silicon spheres obtained in the step (2) in 18mL of ultrapure water, and adding 1mL of the red carbon dot solution obtained in the step (1) and 0.1mmol of Cr3+0.8mL of 0.2mol/L hexadecyl trimethyl ammonium bromide solution is added into the mixed solutionAdding 0.1mL of 0.2mol/L NaOH solution into the solution, adding 200 mu L of ethyl orthosilicate, reacting the mixed solution at room temperature in the dark for 24h, collecting white precipitate, cleaning the white precipitate with an ethanol/acetone mixed solution with a volume ratio of 8:2 to remove hexadecyl trimethyl ammonium bromide, and cleaning the white precipitate with 0.5mol/L EDTA solution to remove Cr3+Then, the mixture is cleaned by ultrapure water and dried in vacuum for standby.
A fluorescent polymer obtainable by any of the methods described above.
The fluorescent polymer is applied to detecting trivalent chromium ions and hexavalent chromium ions by a fluorescent spectrometry method, and high-selectivity fluorescent detection of the hexavalent chromium ions and the trivalent chromium ions is realized by the fluorescent polymer in blue and red excitation channels through an internal filtering effect and electron transfer.
Further, the concentration of the fluorescent polymer in the sample to be detected is 60 mg/L.
The invention has the following beneficial effects:
the fluorescent polymer obtained by the preparation method for simultaneously detecting trivalent chromium ions and hexavalent chromium ions has the following advantages when used for detecting the trivalent chromium ions and the hexavalent chromium ions:
(1) the fluorescent detection of chromium ions in two forms can be directly realized without reducing hexavalent chromium into trivalent chromium or oxidizing the trivalent chromium into hexavalent chromium;
(2) two detection mechanisms are adopted to realize the detection of two chromium ions, and the hexavalent chromium is detected based on the internal filtering effect of the blue carbon point and the hexavalent chromium ions; detecting trivalent chromium ions based on an electron transfer effect between the red carbon dots and the trivalent chromium ions;
(3) two different methods are adopted to eliminate the interference of other ions on the detection, and a mode of coating blue carbon dots in the silicon spheres is adopted to eliminate Co2+Interference to the detection; method for eliminating Fe by adopting ion imprinting3+、Ag+、Pb2+、Cu2+Interference caused by detection of trivalent chromium ions is avoided;
(4) the imprinting layer of the chromium ions is of a mesoporous structure, so that the mass transfer resistance is reduced, and the detection sensitivity is improved;
(5) the red and blue independent excitation channels are adopted to realize the simultaneous detection of the chromium ions in two forms, so that the mutual interference is avoided, and the detection accuracy is high.
Drawings
FIG. 1 is a schematic diagram of the construction method of fluorescence sensing for simultaneously detecting trivalent chromium and hexavalent chromium ions according to the present invention.
FIG. 2 is a fluorescence diagram of the interference test of trivalent chromium ions and hexavalent chromium ions in example 2.
In FIG. 3, A is the fluorescence pattern of the test for eliminating interference with hexavalent chromium ions in example 4, and B is the fluorescence pattern of the test for eliminating interference with trivalent chromium ions.
Detailed Description
The following description of the preferred embodiments of the present invention is provided for the purpose of illustration and description, and is in no way intended to limit the invention.
The invention discloses a fluorescence sensing construction method for simultaneously detecting trivalent chromium ions and hexavalent chromium ions, which mainly comprises the following steps:
(1) preparing a blue carbon dot and a red carbon dot, wherein the excitation wavelength of the blue carbon dot is about 370nm, the emission wavelength is about 450nm, the excitation spectrum of the blue carbon dot is completely overlapped with the absorption spectrum of hexavalent chromium ions, and the excitation spectrum and the absorption spectrum of the hexavalent chromium ions are quenched by the hexavalent chromium ions through an internal filtering effect; the excitation wavelength of the red carbon dot is about 570nm, the emission wavelength is about 600nm, and the red carbon dot can be quenched by trivalent chromium ions based on electron transfer;
(2) coating blue carbon dots inside the silicon spheres;
(3) and coating a fluorescent imprinting layer of trivalent chromium ions on the surface of the silicon ball coated with the blue carbon dots to finally form the fluorescent polymer with the core-shell structure, wherein the fluorescent imprinting layer is doped with the red carbon dots and is of a mesoporous structure.
The fluorescent polymer realizes the high-selectivity fluorescence detection of hexavalent chromium ions and trivalent chromium ions in blue and red excitation channels through an internal filtering effect and electron transfer respectively.
The fluorescence spectrometer used in the following examples was of the type F-7000(Hitachi), and all the starting materials used were commercially available.
Example 1
The preparation method of the fluorescent polymer comprises the following steps:
1. preparation of Red and blue carbon dots
(1) Preparation of blue carbon dots: citric acid (1.2g) + ethylenediamine (2.1mL) was dissolved in 80mL of water, placed in a hydrothermal reaction vessel, and reacted in an oven at 180 ℃ for 8 hours. Taking out, dialyzing to remove unreacted small molecules to obtain a light yellow solution. The optimal excitation wavelength is 350nm, and the emission wavelength is 440 nm.
(2) The red carbon point is prepared by dissolving 2.8g citric acid in 50mL formamide, placing in a hydrothermal reaction kettle, reacting in an oven at 180 ℃ for 8h, taking out, filtering out large particles with a ① 0.22.22 μm microporous membrane, dialyzing to remove small molecules with ②, precipitating with ③ acetone to obtain solid carbon points, and re-dispersing in 50mL water to obtain a brownish red liquid with the optimal excitation wavelength of 570nm and the emission wavelength of 600 nm.
Description of the drawings: the method and raw materials for producing the red carbon dots and the blue carbon dots are not limited thereto, and other raw materials and methods may be used for producing the red carbon dots and the blue carbon dots, but the following points must be satisfied.
(1) The blue carbon point excitation peak has good coincidence degree with the absorption peak of the hexavalent chromium ions, the optimal excitation wavelength is about 370nm, and the hexavalent chromium ions can be quenched through an internal filtering effect.
(2) The red carbon dot is capable of being quenched by trivalent chromium ions.
(3) The excitation wavelength of the red carbon dots cannot be overlapped with the excitation wavelength and the emission wavelength of the blue carbon dots, so that the interference of the two fluorescence intensities is avoided.
2. Coating blue carbon dots inside silicon spheres by a reverse microemulsion method
1.8mL of Triton-100 +1.8mL of n-hexanol was dispersed in 7.5mL of cyclohexane, and then 500. mu.L of blue carbon dot solution was added, 60. mu.L of 28 wt% aqueous ammonia was added, and the mixture was stirred well to form a microemulsion. After 500. mu.L of ethyl orthosilicate was added, the reaction was kept stirring at room temperature for 10 hours. After the reaction is finished, acetone is added into the reaction liquid for demulsification, and white flocculent precipitate is obtained. Collecting white flocculent precipitate, washing with ethanol and water for three times, and vacuum drying for use.
3. Silicon sphere surface coated trivalent chromium ion fluorescent imprinting layer
10mg of blue carbon dot-coated silicon spheres were dispersed in 18mL of ultrapure water, and 1mL of a red carbon dot solution and 0.1mmol of Cr were added3+To the resulting mixed solution, 0.8mL of a cetyltrimethylammonium bromide (CTAB) solution (0.2mol/L) was added, 0.1mL of NaOH (0.2mol/L) was added, 200. mu.L of ethyl orthosilicate was added, and the mixed solution was reacted at room temperature in the dark for 24 hours. The white precipitate was collected and washed repeatedly with ethanol/acetone mixed solution (8:2, v/v) to remove CTAB. Repeatedly cleaning 0.5mol/L EDTA solution to remove Cr3+And then, cleaning with ultrapure water, and drying in vacuum to obtain the fluorescent polymer microspheres for later use.
Description of the drawings:
(1) functional monomers do not need to be added in the imprinting process, functional groups on the surfaces of the red carbon dots are coordinated with trivalent chromium for imprinting, the carbon dots are ensured to be arranged near each recognition site, the conversion efficiency from ion recognition to signal output is increased, and the sensitivity is improved
(2) CTAB is added in the imprinting process to form a mesoporous channel and reduce the mass transfer resistance.
Example 2
The method for testing the mutual interference of trivalent chromium ions and hexavalent chromium ions comprises the following steps:
(1) a solution of the fluorescent polymer microspheres prepared in example 1 at a concentration of 60mg/L was prepared using a PBS (pH 7.0) buffer solution.
(2) Taking 3900 mu L of the solution prepared in the step (1), adding 100 mu L of 400 mu mol/L Cr6+And (3) uniformly mixing the solution (the final ion concentration is 10 mu mol/L), and then putting the solution into a fluorescence spectrometer to detect the fluorescence intensity of the solution under a blue excitation channel.
(3) Collecting 3800 μ L of the solution prepared in step (1), adding 100 μ L of 400 μmol/L Cr6+Solution and 100. mu.L of 400. mu. mol/L Cr3+And (3) uniformly mixing the solutions (the final ion concentrations are all 10 mu mol/L), and then putting the solutions into a fluorescence spectrometer to detect the fluorescence intensity of the solutions under a blue excitation channel. The results are shown in FIG. 2.
The detection result of the blue channel is as follows: cr (chromium) component6+The addition of Cr causes a significant decrease in the fluorescence intensity in the blue channel3+Then, it will not be applied to Cr6+The detection of (2) generates interference.
Detection of the red channel is performed in a similar manner to the blue channel. The results are shown in FIG. 2. The experimental results show that: cr (chromium) component3+The addition of (2) causes significant quenching of the fluorescence intensity in the red channel, the addition of Cr6+Then, it will not be applied to Cr3+The detection of (2) generates interference.
Example 3
And (4) actual water sample detection and standard adding recovery test. The water sample is Yiyi river water in the near-Yiyi region, and is stored in a refrigerator after being filtered by a 0.22 mu M microporous filter. The fluorescence detection method of the present invention was compared with the ICP-MS detection method. When the fluorescence detection method is used, the fluorescent polymer microspheres in example 1 are added into a water sample, and the concentration is 60 mg/L. The method comprises the following steps:
(1) firstly, detecting the concentration of chromium ions in a water sample by using ICP-MS (inductively coupled plasma-mass spectrometry), wherein the chromium ions exist in the undetected water sample. (ICP-MS for total chromium content)
(2) Adding standard to water sample, adding Cr with different concentrations of 0.1, 1.0 and 5.0 mu mol/L6+. Three Cr6+And (3) respectively detecting the water sample by using blue channels of the ICP-MS and the fluorescence spectrometer. And calculating the recovery rate of the added standard.
(3) Adding standard to water sample, adding Cr with different concentrations of 0.1, 1.0 and 5.0 mu mol/L3+. Three Cr3+And (3) detecting the water sample by using red channels of the ICP-MS and the fluorescence spectrometer respectively. And calculating the recovery rate of the added standard.
(4) Adding Cr to water sample6+And Cr3+The concentrations were all 0.5. mu. mol/L. The blue channel of the fluorescence spectrometer for water samples is used for detecting Cr6+Concentration, detection of Cr by Red channel3+The concentration of total chromium was measured by ICP-MS. And calculating the recovery rate of the added standard. The results of the measurements are shown in the following table.
The standard adding test shows that the fluorescence detection method has high accuracy and precision and can simultaneously detect Cr in a sample6+And Cr3+。
Example 4
The interference elimination test is carried out by the following method:
(1) a solution of the fluorescent nanospheres prepared in example 1 at a concentration of 60mg/L was prepared using a buffer solution of PBS (pH 7.0).
(2) Taking 3400 mu L of the solution prepared in the step (1), and respectively adding 100 mu L of 400 mu mol/L Cr6+、Fe3+、Fe2 +、Hg2+、Cr3+、Co2+Different ion solutions (the concentration of each ion is 10 mu mol/L) are uniformly mixed and then put into a fluorescence spectrometer to detect the fluorescence intensity of the solution under a blue excitation channel. The detection conditions are as follows: excitation wavelength 350nm, slit 2.5/2.5 the fluorescence intensity at 440nm is recorded, see A of FIG. 3.
(3) Taking 3200 mu L of the solution prepared in the step (1), and respectively adding 100 mu L of 400 mu mol/L Cr6+、Fe3+、Fe2 +、Hg2+、Cr3+、Co2+、Ag+、Al3+Different ion solutions (the concentration of each ion is 10 mu mol/L) are mixed uniformly and placed in a fluorescence spectrometer for 10min to detect the fluorescence intensity of the solutions under a red excitation channel. The detection conditions are as follows: excitation wavelength 580nm, slit 2.5/2.5, and fluorescence intensity at 605nm is recorded, see B of FIG. 3.
Experiments show that the interference on hexavalent chromium ions is eliminated through silicon ball coating, and the interference on trivalent chromium ions is eliminated through ion imprinting.
Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (7)
1. A method for preparing a fluorescent polymer for simultaneously detecting trivalent chromium ions and hexavalent chromium ions, the method comprising the steps of:
(1) preparing a blue carbon dot and a red carbon dot, wherein the excitation wavelength of the blue carbon dot is about 370nm, the emission wavelength is about 450nm, the excitation spectrum of the blue carbon dot is completely overlapped with the absorption spectrum of hexavalent chromium ions, and the excitation spectrum and the absorption spectrum of the hexavalent chromium ions are quenched by the hexavalent chromium ions through an internal filtering effect; the excitation wavelength of the red carbon dot is about 570nm, the emission wavelength is about 600nm, and the red carbon dot can be quenched by trivalent chromium ions based on electron transfer;
(2) coating blue carbon dots inside the silicon spheres;
(3) and coating a fluorescent imprinting layer of trivalent chromium ions on the surface of the silicon ball coated with the blue carbon dots to finally form the fluorescent polymer with the core-shell structure, wherein the fluorescent imprinting layer is doped with the red carbon dots and is of a mesoporous structure.
2. The method for preparing a fluorescent polymer for simultaneous detection of trivalent chromium ions and hexavalent chromium ions according to claim 1, wherein the blue carbon dots are prepared by the method comprising the steps of: dissolving 1.2g of citric acid and 2.1mL of ethylenediamine in 80mL of water, placing the solution in a hydrothermal reaction kettle, reacting in an oven at 180 ℃ for 8 hours, taking out the solution, and dialyzing the solution to remove unreacted micromolecules to obtain a light yellow blue carbon dot solution;
the preparation method of the red carbon dots comprises the following steps: dissolving 2.8g of citric acid in 50mL of formamide, placing the formamide in a hydrothermal reaction kettle, reacting in an oven at 180 ℃ for 8 hours, taking out the formamide, filtering large particles by using a 0.22-micron microporous filter membrane, dialyzing to remove small molecules, precipitating acetone to obtain solid carbon dots, and then re-dispersing the solid carbon dots in 50mL of water to obtain a brownish red carbon dot solution.
3. The method for preparing a fluorescent polymer for simultaneously detecting trivalent chromium ions and hexavalent chromium ions according to claim 2, wherein in the step (2), the blue carbon dots are coated inside the silica spheres by a reverse microemulsion method, and the specific method comprises the following steps: dispersing 1.8mL of triton-100 and 1.8mL of n-hexanol in 7.5mL of cyclohexane, then adding 500 μ L of the blue carbon dot solution obtained in the step (1), adding 60 μ L of ammonia water with the concentration of 28 wt%, fully stirring to form microemulsion, adding 500 μ L of ethyl orthosilicate, stirring and reacting for 10 hours at room temperature, adding acetone into the reaction liquid after the reaction is finished, demulsifying to obtain white flocculent precipitate, collecting the white flocculent precipitate, washing with ethanol and water for three times respectively, and drying in vacuum for later use.
4. The method for preparing a fluorescent polymer for simultaneously detecting trivalent chromium ions and hexavalent chromium ions according to claim 3, wherein the step (3) of coating the surface of the silicon spheres with the trivalent chromium ion fluorescent imprinted layer comprises the following steps: dispersing 10mg of the blue carbon dot-coated silicon spheres obtained in the step (2) in 18mL of ultrapure water, and adding 1mL of the red carbon dot solution obtained in the step (1) and 0.1mmol of Cr3+Adding 0.8mL of 0.2mol/L hexadecyl trimethyl ammonium bromide solution into the mixed solution, adding 0.1mL of 0.2mol/L NaOH solution into the mixed solution, adding 200 mu L of tetraethoxysilane into the mixed solution, reacting the mixed solution at room temperature in the dark for 24 hours, collecting white precipitates, cleaning the white precipitates by using an ethanol/acetone mixed solution with the volume ratio of 8:2 to remove the hexadecyl trimethyl ammonium bromide, and cleaning the white precipitates by using 0.5mol/L EDTA solution to remove Cr3+Then, the mixture is cleaned by ultrapure water and dried in vacuum for standby.
5. Fluorescent polymers obtainable by the process according to any one of claims 1 to 4.
6. Use of the fluorescent polymer of claim 5 for the detection of trivalent chromium ions and hexavalent chromium ions by fluorescence spectroscopy, said fluorescent polymer enabling highly selective fluorescent detection of hexavalent chromium ions and trivalent chromium ions in blue and red excitation channels by internal filtering effect and electron transfer, respectively.
7. The use according to claim 6, wherein the concentration of the fluorescent polymer in the sample to be tested is 60 mg/L.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911279324.2A CN111088032B (en) | 2019-12-13 | 2019-12-13 | Preparation method of fluorescent polymer for simultaneously detecting trivalent chromium ions and hexavalent chromium ions |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911279324.2A CN111088032B (en) | 2019-12-13 | 2019-12-13 | Preparation method of fluorescent polymer for simultaneously detecting trivalent chromium ions and hexavalent chromium ions |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111088032A true CN111088032A (en) | 2020-05-01 |
| CN111088032B CN111088032B (en) | 2023-07-21 |
Family
ID=70395529
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911279324.2A Active CN111088032B (en) | 2019-12-13 | 2019-12-13 | Preparation method of fluorescent polymer for simultaneously detecting trivalent chromium ions and hexavalent chromium ions |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111088032B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112683871A (en) * | 2021-01-05 | 2021-04-20 | 武双 | Soil chromium ion content detection method |
| CN114034673A (en) * | 2021-10-26 | 2022-02-11 | 华南农业大学 | Carbon dot-based molecular imprinting ratio fluorescent probe and preparation method and application thereof |
| CN114958358A (en) * | 2022-04-29 | 2022-08-30 | 山东大学 | Preparation method of red solid fluorescent powder based on fullerene-like nano carbon |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106566534A (en) * | 2016-11-04 | 2017-04-19 | 中国矿业大学 | Red-light carbon dot of high yield and high quantum yield, and preparation method thereof |
| CN107474248A (en) * | 2017-08-25 | 2017-12-15 | 青岛大学 | A kind of big particle diameter dendritic macromole of fluorescence and preparation method thereof |
| CN109321238A (en) * | 2018-11-14 | 2019-02-12 | 长春工业大学 | A kind of preparation method and application of the carbon quantum dot base fluorescent optical sensor with hexavalent chromium detection function |
-
2019
- 2019-12-13 CN CN201911279324.2A patent/CN111088032B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106566534A (en) * | 2016-11-04 | 2017-04-19 | 中国矿业大学 | Red-light carbon dot of high yield and high quantum yield, and preparation method thereof |
| CN107474248A (en) * | 2017-08-25 | 2017-12-15 | 青岛大学 | A kind of big particle diameter dendritic macromole of fluorescence and preparation method thereof |
| CN109321238A (en) * | 2018-11-14 | 2019-02-12 | 长春工业大学 | A kind of preparation method and application of the carbon quantum dot base fluorescent optical sensor with hexavalent chromium detection function |
Non-Patent Citations (2)
| Title |
|---|
| HONGZHI LU等: "《One Pot Generation of Blue and Red Carbon Dots in One Binary Solvent System for Dual Channel Detection of Cr3+ and Pb2+ Based on Ion Imprinted Fluorescence Polymers》", 《ACS SENSORS》 * |
| HUI DING等: "《Highly Efficient Red-Emitting Carbon Dots with Gram-Scale Yield for Bioimaging》", 《LANGMUIR》 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112683871A (en) * | 2021-01-05 | 2021-04-20 | 武双 | Soil chromium ion content detection method |
| CN112683871B (en) * | 2021-01-05 | 2021-09-21 | 江苏雨松环境修复研究中心有限公司 | Soil chromium ion content detection method |
| CN114034673A (en) * | 2021-10-26 | 2022-02-11 | 华南农业大学 | Carbon dot-based molecular imprinting ratio fluorescent probe and preparation method and application thereof |
| CN114958358A (en) * | 2022-04-29 | 2022-08-30 | 山东大学 | Preparation method of red solid fluorescent powder based on fullerene-like nano carbon |
| CN114958358B (en) * | 2022-04-29 | 2023-08-29 | 山东大学 | Preparation method of red solid fluorescent powder based on fullerene-like nanocarbon |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111088032B (en) | 2023-07-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111088032B (en) | Preparation method of fluorescent polymer for simultaneously detecting trivalent chromium ions and hexavalent chromium ions | |
| CN105949473B (en) | The preparation method and its H of rare earth coordination polymer fluorescence probe2O2With glucose detection application | |
| Chen et al. | Ratiometric fluorescence detection of Cd2+ and Pb2+ by inner filter-based upconversion nanoparticle-dithizone nanosystem | |
| CN109342384B (en) | Visual ratio fluorescence system for detecting cyanide ions and preparation method and application thereof | |
| CN108949171B (en) | Rare earth carbon nano particle, preparation method thereof and application of rare earth carbon nano particle in determination of pH value based on fluorescence chromaticity | |
| CN106932392A (en) | A kind of method of cadmium in gold-silver alloy nanoparticles probe visualization detection water based on cysteine modified | |
| CN106800294B (en) | A kind of graphene quantum dot and the preparation method and application thereof of thymidine modification | |
| CN111141710B (en) | Rapid detection method of metallic mercury | |
| CN103217416B (en) | Detection composition, method and kit for detection of bivalent mercury ions | |
| CN108760702B (en) | Detection method of sulfide ions | |
| CN109612971B (en) | Terbium metal organic framework material and preparation and application thereof | |
| CN114018878B (en) | Method for detecting mercury ions, cadmium ions and/or lead ions based on three-channel fluorescent array sensing | |
| CN110836881A (en) | Method for colorimetric fluorescence detection of antibiotics by graphite-phase carbon nitride/gold nanoparticles | |
| Chen et al. | Amino-functionalized Cu metal–organic framework nanosheets as fluorescent probes for detecting TNP | |
| CN113049547B (en) | Fluorescence determination method for sodium nitrite in nitromethane industrial wastewater | |
| CN113583152B (en) | Cyclodextrin-europium molybdate/lanthanum hybrid microsphere, preparation method thereof and application thereof in fluorescent detection of phosphorus-containing compound | |
| Sun et al. | Inner filter effect-based upconversion fluorescence sensing of sulfide ions | |
| CN111707650A (en) | Method for stepwise detection of Cr (VI) and Cr (III) based on fluorescent carbon quantum dots | |
| CN115960607A (en) | Tetracycline detection material, preparation method thereof and tetracycline detection method | |
| CN115201173B (en) | Method for measuring anionic surfactant in water based on three-dimensional fluorescence | |
| CN115728277B (en) | Method for rapidly detecting content of glyphosate | |
| CN109406507A (en) | The preparation and application of the stabilisation probe of silver ion in a kind of colorimetric detection seawater | |
| CN113466211B (en) | Coprecipitation method for measuring multiple heavy metal elements in seawater | |
| He et al. | Semiquantitative and visual detection of ferric ions in real samples using a fluorescent paper-based analytical device constructed with green emitting carbon dots | |
| CN113480994B (en) | Double-emission cadmium telluride quantum dot fluorescent sensor and application thereof in rapid detection of arsenic ions in water |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |