CN113075186A - Method for detecting zinc dimethyldithiocarbamate based on cesium-lead-bromine quantum dots - Google Patents
Method for detecting zinc dimethyldithiocarbamate based on cesium-lead-bromine quantum dots Download PDFInfo
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- FJDQFPXHSGXQBY-UHFFFAOYSA-L caesium carbonate Chemical compound [Cs+].[Cs+].[O-]C([O-])=O FJDQFPXHSGXQBY-UHFFFAOYSA-L 0.000 claims description 5
- 229910000024 caesium carbonate Inorganic materials 0.000 claims description 5
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- 238000007865 diluting Methods 0.000 claims description 5
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- 239000000126 substance Substances 0.000 claims description 5
- QBVXKDJEZKEASM-UHFFFAOYSA-M tetraoctylammonium bromide Chemical compound [Br-].CCCCCCCC[N+](CCCCCCCC)(CCCCCCCC)CCCCCCCC QBVXKDJEZKEASM-UHFFFAOYSA-M 0.000 claims description 5
- 240000007124 Brassica oleracea Species 0.000 claims description 4
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- 239000000575 pesticide Substances 0.000 description 11
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 description 9
- 239000000463 material Substances 0.000 description 6
- 238000010998 test method Methods 0.000 description 6
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- DKVNPHBNOWQYFE-UHFFFAOYSA-N carbamodithioic acid Chemical compound NC(S)=S DKVNPHBNOWQYFE-UHFFFAOYSA-N 0.000 description 4
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- PFCBRXGBIQWFED-UHFFFAOYSA-N didodecyl(methyl)azanium;bromide Chemical compound [Br-].CCCCCCCCCCCC[NH+](C)CCCCCCCCCCCC PFCBRXGBIQWFED-UHFFFAOYSA-N 0.000 description 3
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- 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
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Abstract
The invention discloses a cesium-lead-bromine quantum dot-based zinc dimethyldithiocarbamate detection method, which comprises the steps of respectively adding zinc dimethyldithiocarbamate standard solutions with different concentrations into cesium-lead-bromine quantum dot indicator solutions, respectively testing the fluorescence intensity of obtained mixed solutions after ultrasonic treatment, and drawing by taking the concentration of zinc dimethyldithiocarbamate as a horizontal coordinate and the fluorescence intensity as a vertical coordinate to obtain a standard curve formula; and then adding the test solution sample into the cesium-lead-bromine quantum dot indicator solution, carrying out ultrasonic treatment, testing the fluorescence intensity of the obtained mixed solution, and calculating to obtain the concentration of the zinc dimethyldithiocarbamate in the test sample by combining a standard curve formula. The invention constructs a simple and convenient zinc dimethyldithiocarbamate detection method based on cesium-lead-bromine quantum dots, does not need a complex sample pretreatment procedure, and has the advantages of simple and convenient operation, low cost and high speed.
Description
Technical Field
The invention belongs to the technical field of rapid detection of pesticides, and particularly relates to a cesium-lead-bromine quantum dot-based zinc dimethyldithiocarbamate detection method.
Background
The cesium-lead-bromine quantum dot material is widely applied to multiple fields of catalysis, electrochemical sensing, energy storage, photoelectric devices and the like due to the excellent optical and electrical properties and the mild preparation method. Although a great deal of research on the application of cesium-lead-bromine quantum dots exists at present, the application of the cesium-lead-bromine quantum dots in optical sensors is still at the beginning. At present, the photochemical sensor based on the cesium-lead-bromine quantum dots can realize the sensing detection of temperature, humidity, gas, solvent content, metal ions and the like. The temperature sensor mainly utilizes the change of temperature to change the lattice expansion degree, electron-phonon coupling effect, phonon-photon interaction and phonon scattering of the hybrid material. The humidity type sensor mainly utilizes the fact that water molecules can form hydrogen bonds with organic components and react with the whole hybrid to form an intermediate, so that the degradation of the hybrid is caused. The solvent-based sensor mainly utilizes the fact that a ligand in a hybrid material is separated from a solvent, and meanwhile, a free ligand in the solvent is combined with the surface of the hybrid material, so that the hybrid material is aggregated, and therefore, the organic-inorganic metal halide hybrid material easily loses structural integrity in a polar solvent, and the optical property is changed. The ionic sensor mainly utilizes the replacement of halogen elements to change the band gap of the nanocrystalline and the exchange and doping of metal ions to influence the symmetry of the crystal, thereby introducing a new luminous energy level.
Dithiocarbamate pesticides typified by zinc dimethyldithiocarbamate are widely used in crop planting, and residue of the pesticides in agricultural products poses great threat to human health and environmental safety. The development of rapid detection methods for such pesticides is of great significance to the monitoring of the use of such pesticides. The traditional mass spectrometry and chromatography detection method has the advantages of high accuracy and high sensitivity, but usually requires special operators, and the pretreatment process is complicated and is not convenient to popularize to the general public. The cesium-lead-bromine quantum dot has the advantages of excellent optical performance and simple and convenient synthesis method, so that the cesium-lead-bromine quantum dot has great application prospect in rapid photochemical sensing detection of pesticides. However, the application of the cesium-lead-bromine quantum dots in the rapid detection of pesticides is still rarely reported, which is mainly because the cesium-lead-bromine quantum dots are unstable in a plurality of solvents, and the luminous intensity of the cesium-lead-bromine quantum dots in a polar solvent is reduced or even disappears.
Disclosure of Invention
The invention aims to provide a simple and convenient method for detecting zinc dimethyldithiocarbamate based on cesium-lead-bromine quantum dots.
In order to achieve the purpose, the invention adopts the following technical scheme:
the detection method of zinc dimethyldithiocarbamate based on cesium-lead-bromine quantum dots is characterized by comprising the following steps: which comprises the following steps:
(1) preparing a liquid sample to be detected: weighing fresh fruits or vegetables, cleaning 1 mL of organic solvent for every 1mg of fruits or vegetables, and taking the cleaned solution as a sample of a solution to be detected;
(2) preparing a cesium-lead-bromine quantum dot indicator: placing the cesium-lead-bromine quantum dots in a reaction bottle, and diluting the cesium-lead-bromine quantum dots to 0.001-100 mol/L by using an organic solvent to serve as a cesium-lead-bromine quantum dot indicator solution;
(3) and (3) preparing a standard curve: adding zinc dimethyldithiocarbamate standard solutions with different concentrations into a cesium lead bromine quantum dot indicator solution respectively, carrying out ultrasonic treatment, testing the fluorescence intensity of the obtained mixed solution respectively, and drawing by taking the concentration of the zinc dimethyldithiocarbamate as a horizontal coordinate and the fluorescence intensity as a vertical coordinate to obtain a standard curve formula;
(4) and (3) determination of a liquid sample to be determined: and adding the test solution sample into the cesium-lead-bromine quantum dot indicator solution, carrying out ultrasonic treatment, testing the fluorescence intensity of the obtained mixed solution, and calculating to obtain the concentration of the zinc dimethyldithiocarbamate in the test sample by combining a standard curve formula.
Further, the fruit and vegetable is one of apple, pear, peach, plum, apricot, cherry, grape, tomato, celery, cabbage, garland chrysanthemum, cabbage, radish and spinach.
Further, the organic solvent is one of toluene, n-hexane or cyclohexane.
Further, the cesium lead bromide quantum dot is prepared by adopting cesium carbonate dissolved in octanoic acid as a cesium precursor solution, lead bromide dissolved in toluene and tetraoctylammonium bromide as a lead precursor solution, and injecting the cesium precursor solution into the lead precursor solution under stirring at room temperature.
Further, the manufacturing method of the standard curve specifically comprises the following steps: weighing zinc dimethyldithiocarbamate standard substances, and preparing 5 zinc dimethyldithiocarbamate standard solutions with the concentrations of 1 ppm, 5 ppm, 10 ppm, 50 ppm and 100 ppm in sequence by adopting an organic solvent; transferring the cesium-lead-bromine quantum dot indicator solution into 5 reaction bottles, wherein the cesium-lead-bromine quantum dot indicator solution in each reaction bottle has equal volume and is A (1-10) mL; transferring 5 zinc dimethyldithiocarbamate standard solutions with B (1-10) mL concentrations of 1 ppm, 5 ppm, 10 ppm, 50 ppm and 100 ppm in sequence, adding the 5 reaction bottles into the 5 reaction bottles, carrying out ultrasonic treatment on the 5 reaction bottles for 5 minutes, transferring mixed liquid in the C (1-10) mL reaction bottles in sequence, testing the fluorescence intensity of the mixed liquid, taking the excitation light wavelength as 365 nm, taking the concentration of the zinc dimethyldithiocarbamate as a horizontal coordinate, taking the fluorescence intensity as a vertical coordinate, drawing a scatter diagram, and adding a linear trend line to obtain a standard curve and a standard curve formula y = ax + B, wherein y is the fluorescence intensity value, x is the concentration of the zinc dimethyldithiocarbamate, and a and B are constants.
Further, the determination steps of the liquid sample to be determined are as follows: transferring A (1-10) mL of cesium lead bromide quantum dot indicator solution into a reaction bottle, then transferring B (1-10) mL of to-be-detected liquid sample into the reaction bottle, carrying out ultrasonic treatment on the reaction bottle for 5 minutes, finally transferring C (1-10) mL of mixed liquid in the reaction bottle, testing the fluorescence intensity of the mixed liquid, wherein the wavelength of excitation light is 365 nm, substituting the measured fluorescence intensity value into a standard curve formula y = ax + B, and calculating to obtain the concentration of zinc dimethyldithiocarbamate in the to-be-detected sample.
The invention constructs a simple and convenient zinc dimethyldithiocarbamate detection method based on cesium-lead-bromine quantum dots, does not need a complex sample pretreatment procedure, and has the advantages of simple and convenient operation, low cost and high speed. The rapid detection method of zinc dimethyldithiocarbamate provided by the invention is expected to be used for real-time on-site monitoring of the use condition of zinc dimethyldithiocarbamate pesticides in each link of agricultural product production and transportation, and has important significance for food-borne early warning of pesticide residues in agricultural products.
Drawings
FIG. 1 is a standard graph of examples 1 and 2, wherein the concentration of zinc dimethyldithiocarbamate is in the range of 1-100 ppm;
FIG. 2 is a graph showing the change in fluorescence of cesium lead bromide quantum dots after adding zinc dimethyldithiocarbamate at different concentrations in examples 1 and 2.
Detailed Description
The present invention is further described in detail below with reference to specific examples, which are provided for illustration only and are not intended to limit the invention.
Example 1
The method for detecting the zinc dimethyldithiocarbamate in the apples based on the cesium-lead-bromine quantum dots comprises the following steps:
(1) preparing a liquid sample to be detected: 5 g of apples are weighed, washed with 5 mL of toluene, and the washed solution is used as a sample of a solution to be tested.
(2) Preparing a cesium-lead-bromine quantum dot indicator: firstly, 0.325 g of cesium carbonate is weighed and dissolved in 10 mL of caprylic acid to be used as a cesium precursor solution; weighing 0.367 g of lead bromide and 1.092 g of tetraoctylammonium bromide, and dissolving in 10 mL of toluene to obtain a lead precursor solution; next, 1 mL of the cesium precursor solution was injected into 10 mL of the lead precursor solution under stirring at room temperature, and the mixture was stirred for 2 minutes. Then, 3 mL of a toluene solution of didodecylmethylammonium bromide at a concentration of 10 mg/mL was poured into the above liquid, and stirred for 3 minutes. A further 28 mL of ethyl acetate was added and centrifuged to give a solid which was redispersed in 10 mL of toluene. And finally, transferring the prepared cesium lead bromine quantum dots into a reaction vial, and diluting the cesium lead bromine quantum dots to 0.001 mol/L by adopting toluene to serve as cesium lead bromine quantum dot indicator solution.
(3) And (3) sample determination: the method comprises the steps of preparing a standard curve and measuring a sample.
And (3) preparing a standard curve: firstly, weighing zinc dimethyldithiocarbamate standard substances, and preparing 5 zinc dimethyldithiocarbamate standard solutions with the concentrations of 1 ppm, 5 ppm, 10 ppm, 50 ppm and 100 ppm in sequence by adopting toluene. And secondly, transferring the cesium lead bromine quantum dot indicator solution into 5 reaction vials, wherein the cesium lead bromine quantum dot indicator solution in each vial has the same volume, and is 2 ml. Subsequently, 1 ml of 5 kinds of zinc dimethyldithiocarbamate standard solutions having concentrations of 1 ppm, 5 ppm, 10 ppm, 50 ppm and 100 ppm were sequentially transferred and added to the above 5 reaction vials. 5 reaction vials were sonicated for 5 minutes. And sequentially and respectively transferring the mixed liquid in a 2 ml reaction vial, and testing the fluorescence intensity of the mixed liquid, wherein the wavelength of the excitation light is 365 nm. The concentration of zinc dimethyldithiocarbamate is plotted on the abscissa and the fluorescence intensity is plotted on the ordinate, a scatter plot is made, and a linear trend line is added to obtain a standard curve and a standard linear formula y = -18.504x + 3170 (wherein y is the fluorescence intensity value and x is the concentration of zinc dimethyldithiocarbamate).
And (3) determination of a sample: first, 2 ml of cesium lead bromide quantum dot indicator solution was removed from the reaction vial, and then 1 ml of the sample of the solution to be tested was removed from the reaction vial. The reaction vial was sonicated for 5 minutes. Finally, the mixed liquid in a 2 ml reaction vial was removed, and the fluorescence intensity was measured to be 3160 and the excitation light wavelength was measured to be 365 nm. And substituting the measured fluorescence intensity value of y =3150 into a standard linear formula of y = -18.504x + 3170, and calculating to obtain a value of x =1.08, namely the concentration of the zinc dimethyldithiocarbamate in the sample to be detected. The measured concentration of the zinc dimethyldithiocarbamate in the apples is 1.08 ppm, which is similar to the data 1.01 ppm measured by the national standard dithiocarbamate pesticide test method, and the test method of the zinc dimethyldithiocarbamate is feasible.
Example 2
A detection method of zinc dimethyldithiocarbamate in grapes based on cesium-lead-bromine quantum dots comprises the following steps:
(1) preparing a liquid sample to be detected: 10 g of grapes are weighed, washed with 10 mL of toluene, and the washed solution is used as a sample of a solution to be tested.
(2) Preparing a cesium-lead-bromine quantum dot indicator: firstly, 0.325 g of cesium carbonate is weighed and dissolved in 10 mL of caprylic acid to be used as a cesium precursor solution; weighing 0.367 g of lead bromide and 1.092 g of tetraoctylammonium bromide, and dissolving in 10 mL of toluene to obtain a lead precursor solution; next, 1 mL of the cesium precursor solution was injected into 10 mL of the lead precursor solution under stirring at room temperature, and the mixture was stirred for 2 minutes. Then, 3 mL of a toluene solution of didodecylmethylammonium bromide at a concentration of 10 mg/mL was poured into the above liquid, and stirred for 3 minutes. A further 28 mL of ethyl acetate was added and centrifuged to give a solid which was redispersed in 10 mL of toluene. And finally, transferring the prepared cesium lead bromine quantum dots into a reaction vial, and diluting the cesium lead bromine quantum dots to 0.001 mol/L by adopting toluene to serve as cesium lead bromine quantum dot indicator solution.
(3) And (3) sample determination: the method comprises the steps of preparing a standard curve and measuring a sample.
And (3) preparing a standard curve: firstly, weighing zinc dimethyldithiocarbamate standard substances, and preparing 5 zinc dimethyldithiocarbamate standard solutions with the concentrations of 1 ppm, 5 ppm, 10 ppm, 50 ppm and 100 ppm in sequence by adopting toluene. And secondly, transferring the cesium lead bromine quantum dot indicator solution into 5 reaction vials, wherein the cesium lead bromine quantum dot indicator solution in each vial has the same volume, and is 2 ml. Subsequently, 1 ml of 5 kinds of zinc dimethyldithiocarbamate standard solutions having concentrations of 1 ppm, 5 ppm, 10 ppm, 50 ppm and 100 ppm were sequentially transferred and added to the above 5 reaction vials. 5 reaction vials were sonicated for 5 minutes. And sequentially and respectively transferring the mixed liquid in a 2 ml reaction vial, and testing the fluorescence intensity of the mixed liquid, wherein the wavelength of the excitation light is 365 nm. The concentration of zinc dimethyldithiocarbamate is plotted on the abscissa and the fluorescence intensity is plotted on the ordinate, a scatter plot is made, and a linear trend line is added to obtain a standard curve and a standard linear formula y = -18.504x + 3170 (wherein y is the fluorescence intensity value and x is the concentration of zinc dimethyldithiocarbamate).
And (3) determination of a sample: first, 2 ml of cesium lead bromide quantum dot indicator solution was removed from the reaction vial, and then 1 ml of the sample of the solution to be tested was removed from the reaction vial. The reaction vial was sonicated for 5 minutes. Finally, the mixed liquid in a 2 ml reaction vial was removed, and the fluorescence intensity was measured to be 3145 and the excitation light wavelength was measured to be 365 nm. And substituting the measured fluorescence intensity value of y =3145 into a standard linear formula of y = -18.504x + 3170, and calculating to obtain a value of x =1.35, namely the concentration of the zinc dimethyldithiocarbamate in the sample to be detected. The measured concentration of the zinc dimethyldithiocarbamate in the grapes is 1.35 ppm which is similar to the data 1.05 ppm measured by the national standard dithiocarbamate pesticide test method, and the test method of the zinc dimethyldithiocarbamate is feasible.
Example 3
The method for detecting the zinc dimethyldithiocarbamate in celery based on the cesium-lead-bromine quantum dots comprises the following steps:
(1) preparing a liquid sample to be detected: weighing 8 g of celery, washing with 8 mL of n-hexane, and taking the washed solution as a sample of the solution to be detected.
(2) Preparing a cesium-lead-bromine quantum dot indicator: firstly, 0.325 g of cesium carbonate is weighed and dissolved in 10 mL of caprylic acid to be used as a cesium precursor solution; weighing 0.367 g of lead bromide and 1.092 g of tetraoctylammonium bromide, and dissolving in 10 mL of toluene to obtain a lead precursor solution; next, 1 mL of the cesium precursor solution was injected into 10 mL of the lead precursor solution under stirring at room temperature, and the mixture was stirred for 2 minutes. Then, 3 mL of a toluene solution of didodecylmethylammonium bromide at a concentration of 10 mg/mL was poured into the above liquid, and stirred for 3 minutes. A further 28 mL of ethyl acetate was added and centrifuged to give a solid which was redispersed in 10 mL of toluene. And finally, transferring the prepared cesium-lead-bromine quantum dots into a reaction vial, and diluting the cesium-lead-bromine quantum dots to 0.001 mol/L by adopting n-hexane to serve as cesium-lead-bromine quantum dot indicator solution.
(3) And (3) sample determination: the method comprises the steps of preparing a standard curve and measuring a sample.
And (3) preparing a standard curve: firstly, weighing zinc dimethyldithiocarbamate standard substances, and preparing 5 zinc dimethyldithiocarbamate standard solutions with the concentrations of 1 ppm, 5 ppm, 10 ppm, 50 ppm and 100 ppm in sequence by adopting n-hexane. And secondly, transferring the cesium lead bromine quantum dot indicator solution into 5 reaction vials, wherein the cesium lead bromine quantum dot indicator solution in each vial has the same volume, and is 5 ml. Subsequently, 2 ml of 5 kinds of zinc dimethyldithiocarbamate standard solutions having concentrations of 1 ppm, 5 ppm, 10 ppm, 50 ppm and 100 ppm were sequentially transferred and added to the above 5 reaction vials. 5 reaction vials were sonicated for 5 minutes. And sequentially and respectively transferring the mixed liquid in a 3 ml reaction vial, and testing the fluorescence intensity of the mixed liquid, wherein the wavelength of the excitation light is 365 nm. The concentration of zinc dimethyldithiocarbamate is plotted on the abscissa and the fluorescence intensity is plotted on the ordinate, a scatter plot is made, and a linear trend line is added to obtain a standard curve and a standard linear formula y = -26.504x + 3270 (wherein y is the fluorescence intensity value, x is the concentration of zinc dimethyldithiocarbamate, and a and b are constants).
And (3) determination of a sample: first, 5 ml of cesium lead bromide quantum dot indicator solution was removed from the reaction vial, and then 2 ml of the sample of the solution to be tested was removed from the reaction vial. The reaction vial was sonicated for 5 minutes. Finally, the mixed liquid in a 3 ml reaction vial was removed and tested for fluorescence intensity 3133 and excitation light wavelength 365 nm. And substituting the measured fluorescence intensity as a y value into a standard linear formula y = -26.504x + 3270, and calculating to obtain x =5.17, namely the concentration of the zinc dimethyldithiocarbamate in the sample to be measured. The measured concentration of the zinc dimethyldithiocarbamate in the celery is 5.17 ppm, which is similar to the data measured by the national standard dithiocarbamate pesticide test method, namely 4.99 ppm, and the test method of the zinc dimethyldithiocarbamate disclosed by the invention is feasible.
The foregoing is illustrative of the preferred embodiments of the present invention and is not to be construed as limiting the invention to the precise embodiments set forth herein. Any changes and modifications made according to the present invention without departing from the spirit and scope of the present invention are within the scope of the claims of the present invention and their equivalents.
Claims (7)
1. The detection method of zinc dimethyldithiocarbamate based on cesium-lead-bromine quantum dots is characterized by comprising the following steps: which comprises the following steps:
(1) preparing a liquid sample to be detected: weighing fresh fruits or vegetables, cleaning 1 mL of organic solvent for every 1mg of fruits or vegetables, and taking the cleaned solution as a sample of a solution to be detected;
(2) preparing a cesium-lead-bromine quantum dot indicator: placing the cesium-lead-bromine quantum dots in a reaction bottle, and diluting the cesium-lead-bromine quantum dots to 0.001-100 mol/L by using an organic solvent to serve as a cesium-lead-bromine quantum dot indicator solution;
(3) and (3) preparing a standard curve: adding zinc dimethyldithiocarbamate standard solutions with different concentrations into a cesium lead bromine quantum dot indicator solution respectively, carrying out ultrasonic treatment, testing the fluorescence intensity of the obtained mixed solution respectively, and drawing by taking the concentration of the zinc dimethyldithiocarbamate as a horizontal coordinate and the fluorescence intensity as a vertical coordinate to obtain a standard curve formula;
(4) and (3) determination of a liquid sample to be determined: and adding the test solution sample into the cesium-lead-bromine quantum dot indicator solution, carrying out ultrasonic treatment, testing the fluorescence intensity of the obtained mixed solution, and calculating to obtain the concentration of the zinc dimethyldithiocarbamate in the test sample by combining a standard curve formula.
2. The preparation method of the cesium lead bromide quantum dot-based zinc dimethyldithiocarbamate detection method according to claim 1, wherein the method comprises the following steps: the fruit and vegetable is one of apple, pear, peach, plum, apricot, cherry, grape, tomato, celery, cabbage, crowndaisy chrysanthemum, cabbage, radish and spinach.
3. The preparation method of the cesium lead bromide quantum dot-based zinc dimethyldithiocarbamate detection method according to claim 1, wherein the method comprises the following steps: the organic solvent is one of toluene, n-hexane or cyclohexane.
4. The preparation method of the cesium lead bromide quantum dot-based zinc dimethyldithiocarbamate detection method according to claim 1, wherein the method comprises the following steps: the cesium-lead-bromine quantum dot is prepared by adopting cesium carbonate dissolved in octanoic acid as a cesium precursor solution, lead bromide dissolved in toluene and tetraoctylammonium bromide as a lead precursor solution, and injecting the cesium precursor solution into the lead precursor solution under stirring at room temperature.
5. The preparation method of the cesium lead bromide quantum dot-based zinc dimethyldithiocarbamate detection method according to claim 1, wherein the method comprises the following steps: the manufacturing method of the standard curve comprises the following specific steps:
weighing zinc dimethyldithiocarbamate standard substances, and preparing 5 zinc dimethyldithiocarbamate standard solutions with the concentrations of 1 ppm, 5 ppm, 10 ppm, 50 ppm and 100 ppm in sequence by adopting an organic solvent;
transferring the cesium-lead-bromine quantum dot indicator solution into 5 reaction bottles, wherein the cesium-lead-bromine quantum dot indicator solution in each reaction bottle is equal in volume and is A mL;
transferring 5 zinc dimethyldithiocarbamate standard solutions with B mL concentrations of 1 ppm, 5 ppm, 10 ppm, 50 ppm and 100 ppm in sequence, adding the 5 reaction bottles, carrying out ultrasonic treatment on the 5 reaction bottles for 5 minutes, transferring mixed liquid in the C mL reaction bottles in sequence, testing the fluorescence intensity of the mixed liquid, drawing a graph by taking the concentration of the zinc dimethyldithiocarbamate as a horizontal coordinate and the fluorescence intensity as a vertical coordinate, taking the graph as a scatter diagram, and adding a linear trend line to obtain a standard curve and a standard curve formula y = ax + B, wherein y is a fluorescence intensity value, x is the concentration of the zinc dimethyldithiocarbamate, and a and B are constants.
6. The preparation method of the cesium lead bromide quantum dot-based zinc dimethyldithiocarbamate detection method according to claim 5, wherein the method comprises the following steps: the steps for measuring the liquid sample to be measured are as follows: transferring A mL of cesium-lead-bromine quantum dot indicator solution into a reaction bottle, then transferring B mL of to-be-detected liquid sample into the reaction bottle, carrying out ultrasonic treatment on the reaction bottle for 5 minutes, finally transferring the mixed liquid in the C mL reaction bottle, testing the fluorescence intensity of the mixed liquid, wherein the wavelength of the excitation light is 365 nm, substituting the measured fluorescence intensity value into a standard curve formula y = ax + B, and calculating to obtain the concentration of the zinc dimethyldithiocarbamate in the to-be-detected sample.
7. The preparation method of the cesium lead bromide quantum dot-based zinc dimethyldithiocarbamate detection method according to claim 5 or 6, wherein the cesium lead bromide quantum dot-based zinc dimethyldithiocarbamate detection method comprises the following steps: the A, B, C values were all 1-10 mL.
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