A method for detecting the content of 1-adamantanecarboxylic acid in soil and water by gas chromatography

Abstract

The present invention discloses a method for detecting the content of 1 - adamantanecarboxylic acid in soil and water by gas chromatography. The method comprises the following steps: (1) preparation of a standard working solution; (2) preparation of a sample solution; (3) determination and calculation. The present invention uses an FID detector and employs an HP - 5 (30m × 0.32mm, 0.25μm) chromatographic column to detect 1 - adamantanecarboxylic acid in soil and water, and quantitative analysis is carried out by the external standard method. The present invention has the characteristics of strong specificity, good repeatability, high recovery rate, high detection efficiency, sensitive method and accurate results.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental detection, and particularly relates to a method for detecting the content of 1-adamantane carboxylic acid in soil and water by gas chromatography. Background Art

[0002] Adamantane is a cage hydrocarbon with a regular symmetry and high stability, and it has a wide range of applications in medicine, functional polymers, surfactants, lubricants, light-sensitive materials, aviation and so on.

[0003] 1-Adamantane Carboxylic Acid, with the molecular formula C 11 H 16 O2, CAS number 828-51-3, and its chemical structural formula is as follows:

[0004]

[0005] 1-Adamantane Carboxylic Acid is generally synthesized by the Koch-haaf reaction from adamantane and its derivatives. It is a white crystalline powder and can be used as an intermediate to synthesize adamantane ethylamine hydrochloride, and it has good application prospects in medicine and light-sensitive materials.

[0006] Discharging undiluted products or products with a high content of 1-adamantane carboxylic acid into the water or soil environment will cause environmental pollution of soil and water bodies. At present, there is no reported detection method for 1-adamantane carboxylic acid. Developing an effective method for detecting the content of 1-adamantane carboxylic acid in soil and water bodies is very important for the environmental protection of soil and water bodies at the production and use sites of 1-adamantane carboxylic acid. Summary of the Invention

[0007] The object of the present invention is to provide a method for detecting the content of 1-adamantanecarboxylic acid in soil and water by gas chromatography, and the steps are as follows: (1) Preparation of standard working solution: Accurately weigh 0.10105 g of 1-adamantanecarboxylic acid standard sample into a 100 mL volumetric flask, dissolve it with ethanol and make up to the scale, shake well, and prepare a 1-adamantanecarboxylic acid standard stock solution with a concentration of 1000.40 mg / L; Absorb an appropriate amount of the standard stock solution and dilute it with acetonitrile to obtain a series of gradient concentration standard working solutions. (2) Preparation of sample solution to be measured: ① Soil: Collect the soil sample to be measured, and reserve it after pretreatment such as impurity removal, air drying, and sieving. Weigh 5.0 - 15.0 g of the pretreated soil sample into a 250 mL conical flask, add 45 - 55 mL of ethanol and 0.2 mL of glacial acetic acid to the conical flask, shake for 25 - 35 min, let it stand, and take the supernatant and filter it through a 0.45 μm filter membrane to obtain the soil sample solution to be measured. ② Water body: Absorb 15 - 25 mL of the water body sample into a 100 mL conical flask, add excessive potassium chloride to saturate it, add 15 - 25 mL of acetonitrile and manually shake for 5 - 15 min, take out the supernatant, add an appropriate amount of anhydrous sodium sulfate to remove the excess water, and filter it through a 0.45 μm filter membrane to obtain the water body sample solution to be measured. (3) Determination and calculation: Set the instrument parameters of the gas chromatograph. After the instrument is stable, absorb 0.5 - 1.5 μL of the standard working solution, soil sample solution, and water body sample solution prepared in step (1) and step (2) for determination, record the chromatogram, and calculate the content of 1-adamantanecarboxylic acid in the sample to be measured by the external standard method.

[0008] Preferably, the steps are as follows: (1) Preparation of standard working solution: accurately weigh 0.10105g of 1-adamantanecarboxylic acid standard sample into a 100mL volumetric flask, dissolve it with ethanol and adjust the volume, shake well, and prepare a 1-adamantanecarboxylic acid standard stock solution with a concentration of 1000.40mg / L; take an appropriate amount of the standard stock solution and dilute it with acetonitrile to obtain a series of gradient concentration standard working solutions. (2) Preparation of the sample solution to be tested: ① Soil: collect the soil sample to be tested, remove impurities, air-dry, and sieve for pretreatment before use, weigh 8.0-12.0g of the pretreated soil sample into a 250mL conical flask, add 48-52mL of ethanol and 0.2mL of glacial acetic acid to the conical flask, shake for 28-32min, let it stand, take the supernatant and filter it with a 0.45μm filter membrane to obtain the soil sample solution to be tested. ② Water: Pipette 18-22 mL of water sample into a 100 mL conical flask, add excess potassium chloride to saturate it, add 18-22 mL of acetonitrile and shake manually for 8-12 minutes, remove the supernatant, add an appropriate amount of anhydrous sodium sulfate to remove excess water, and filter with a 0.45 μm filter membrane to obtain the water sample solution to be tested. (3) Determination and calculation: Set the instrument parameters of the gas chromatograph, wait for the instrument to stabilize, and take 0.8-1.2 μL of the standard working solution, soil sample solution, and water sample solution prepared in step (1) and step (2) for determination, record the chromatogram, and calculate the content of 1-adamantancarboxylic acid in the sample to be tested by the external standard method.

[0009] More preferably, the steps are as follows: (1) Preparation of standard working solution: accurately weigh 0.10105g of 1-adamantanecarboxylic acid standard sample into a 100mL volumetric flask, dissolve it with ethanol and adjust the volume to the mark, shake well, and prepare a 1-adamantanecarboxylic acid standard stock solution with a concentration of 1000.40mg / L; take an appropriate amount of the standard stock solution and dilute it with acetonitrile to obtain a series of gradient concentration standard working solutions. (2) Preparation of the sample solution to be tested: ① Soil: collect the soil sample to be tested, remove impurities, air-dry, and sieve for pretreatment before use, weigh 10.0g of the pretreated soil sample into a 250mL conical flask, add 50mL of ethanol and 0.2mL of glacial acetic acid to the conical flask, shake for 30min, let it stand, take the supernatant and filter it with a 0.45μm filter membrane to obtain the soil sample solution to be tested. Water: Pipette 20 mL of water sample into a 100 mL conical flask, add excess potassium chloride to saturate it, add 20 mL of acetonitrile and shake manually for 10 min, remove the supernatant, add an appropriate amount of anhydrous sodium sulfate to remove excess water, and filter with a 0.45 μm filter membrane to obtain the water sample solution to be tested. (3) Determination and calculation: Set the instrument parameters of the gas chromatograph, and after the instrument is stable, pipette 1.0 μL of the standard working solution, soil sample solution, and water sample solution prepared in steps (1) and (2) for determination, record the chromatogram, and calculate the content of 1-adamantanescarboxylic acid in the sample to be tested by the external standard method.

[0010] The concentrations of the series of gradient concentration standard working solutions in step (1) are 0.80 mg / L, 1.00 mg / L, 2.00 mg / L, 4.00 mg / L, 6.00 mg / L, 8.00 mg / L, and 10.0 mg / L respectively.

[0011] The operating conditions of the gas chromatograph are as follows:

[0012] Detector: FID;

[0013] Chromatographic column: HP-5, 30 m × 0.32 mm, 0.25 μm;

[0014] Flow ratio: pulsed splitless;

[0015] Temperature: Vaporization chamber temperature 260 - 280 °C; detector temperature 280 - 300 °C; column oven: initial temperature 90 - 110 °C, hold for 1 min, increase the temperature at a rate of 10 °C / min to 250 °C, hold for 0 min, increase the temperature at a rate of 50 °C / min to 300 °C, hold for 5 min;

[0016] Gas: Air: 400 mL / min; hydrogen: 40 mL / min; carrier gas (N2): 0.5 - 1.5 mL / min; tail gas blow (N2): 20 mL / min.

[0017] Preferably, the vaporization chamber temperature is 265 - 275 °C, the detector temperature is 285 - 295 °C, and the initial temperature of the column oven is 95 - 105 °C.

[0018] More preferably, the vaporization chamber temperature is 270 °C, the detector temperature is 280 °C, and the initial temperature of the column oven is 100 °C.

[0019] Preferably, the flow rate of the carrier gas (N2) is 0.8 - 1.2 mL / min.

[0020] More preferably, the flow rate of the carrier gas (N2) is 1.0 mL / min.

[0021] The LOD of this method for 1-adamantanecarboxylic acid is 0.10 mg / L, and the LOQ is 0.22 mg / L.

[0022] Advantages of the present invention:

[0023] 1. The method of the present invention can be used to detect 1-adamantanecarboxylic acid in soil and water environments. The detection limit LOD of 1-adamantanecarboxylic acid by this method is 0.10 mg / L, and the LOQ is 0.22 mg / L. It can still achieve the detection purpose when the sample concentration is low, providing a technical reference for the detection of 1-adamantanecarboxylic acid in soil and water environments and related research on subsequent quality control of 1-adamantanecarboxylic acid. The method of the present invention has the advantages of simple operation steps for sample treatment, strong specificity, good repeatability, high recovery rate, high efficiency, sensitivity, accuracy, wide application range, small amount of required sample, and easy mastery of equipment and operation.

[0024] 2. The results of the method validation test of the present invention show that 1-adamantanecarboxylic acid of the present invention elutes at 7.5 min, and there is no interference peak at this time point in the blank sample, indicating good specificity of this method for 1-adamantanecarboxylic acid. 1-adamantanecarboxylic acid of this method shows a good linear relationship in the range of 0.80 mg / L - 10.0 mg / L, with the linear equation y = 8.5952x - 4.8097 and the linear correlation coefficient R 2 = 0.9987. The RSD R.T. of the target peak is 0.01%, and the RSD Area is 4.97%, both less than 5.00%, indicating good repeatability. The average spiked recoveries of 1-adamantanecarboxylic acid of the present invention in soil and water can reach 105.2% and 101.5% respectively. Description of the Drawings

[0025] Figure 1 is the calibration curve of 1-adamantanecarboxylic acid;

[0026] Figure 2 is the typical chromatogram of the calibration curve of 1-adamantanecarboxylic acid (8.00 mg / L);

[0027] Figure 3 is the typical chromatogram of the repeatability of 1-adamantanecarboxylic acid (4.00 mg / L);

[0028] Figure 4 is the typical chromatogram of the detection limit of 1-adamantanecarboxylic acid (1.00 mg / L);

[0029] Figure 5 is the typical chromatogram of the quantitation limit of 1-adamantanecarboxylic acid (0.80 mg / L);

[0030] Figure 6 is the typical chromatogram of the spiked recovery of 1-adamantanecarboxylic acid in soil (blank control);

[0031] Figure 7 is the typical chromatogram of the spiked recovery of 1-adamantanecarboxylic acid in soil (1.00 mg / L);

[0032] Figure 8 Typical chromatogram of the recovery rate of adding 1-adamantanecarboxylic acid in soil (5.00 mg / L);

[0033] Figure 9 Typical chromatogram of the recovery rate of adding 1-adamantanecarboxylic acid in water (blank control);

[0034] Figure 10 Typical chromatogram of the recovery rate of adding 1-adamantanecarboxylic acid in water (1.00 mg / L);

[0035] Figure 11 Typical chromatogram of the recovery rate of adding 1-adamantanecarboxylic acid in water (5.00 mg / L). Specific implementation manners

[0036] The present invention will be described in detail below with reference to specific embodiments and the accompanying drawings. The following are only several specific embodiments listed for those skilled in the art to understand the present invention, and are not used to limit the scope claimed by the present invention. Therefore, any equivalent changes or modifications made according to the features, structures and principles described in the claims of the present invention should be included within the scope of the claims of the present invention.

[0037] The test instruments, equipment and reagents used in the following embodiments and methodological verification tests include but are not limited to:

[0038] 1. Instrument equipment

[0039] (1) Gas chromatograph: Agilent Technologies, Inc., USA, Agilent 8860, FID detector;

[0040] (2) Electronic balance: Mettler Toledo (China) Co., Ltd., XSE205DU;

[0041] (3) Electronic balance: Mettler Toledo (Changzhou) Measuring Technology Co., Ltd., PL1002E / 02;

[0042] (4) Constant temperature incubator shaker: Shanghai Zicheng Analytical Instrument Manufacturing Co., Ltd., ZWY-240;

[0043] (5) Common glass instruments such as volumetric flasks and pipettes.

[0044] 2. Reagents

[0045] (1) 1-adamantanecarboxylic acid standard sample, purity ≥ 99%;

[0046] (2) Ethanol: HPLC, ANPEL Inc., batch number: U0610432;

[0047] (3) Acetonitrile: HPLC, ANPEL Inc., batch number: X4851440;

[0048] (4) Potassium chloride: Analytically pure, produced by Tianjin Zhiyuan Chemical Reagent Co., Ltd., batch number: 2018052053;

[0049] (5) Anhydrous sodium sulfate: Analytically pure, produced by Chengdu Kelong Chemical Reagent Factory, batch number 2016041501.

[0050] 3. Test samples

[0051] The soil in the following examples is the paddy soil T2020002 from Shaoxing City, Zhejiang Province, purchased from the Ministry of Agriculture and Rural Affairs. After air-drying, the soil was passed through a 1.0 mm sieve and stored in the dark at room temperature for later use.

[0052] The preparation steps of the soil sample in the following examples are as follows: Weigh 10.0 g of the above-mentioned paddy soil into a 250 mL conical flask, add 0.50 mL of the standard stock solution of 1-adamantanecarboxylic acid with a concentration of 1000.4 mg / L prepared according to the method of the present invention, mix well, and prepare a soil sample with a 1-adamantanecarboxylic acid concentration of 50.0 mg / kg.

[0053] In the following examples, UP water is used as a representative of environmental water bodies. The UP water comes from the tap water in our laboratory and is taken after being prepared by an ultrapure water machine. The resistivity of the UP water is 18.2 MΩ×cm.

[0054] The preparation steps of the water sample in the following examples are as follows: Pipette 1.00 mL of the standard stock solution with a concentration of 1000.4 mg / L prepared according to the method of the present invention into a 100 mL volumetric flask, and make up the volume with UP water to obtain a water sample with a 1-adamantanecarboxylic acid concentration of 10.0 mg / L.

[0055] Example 1

[0056] (1) Preparation of the standard working solution: Weigh accurately 0.10105 g of 1-adamantanecarboxylic acid standard sample into a 100 mL volumetric flask, dissolve it with ethanol and make up the volume to the scale, shake well, and prepare a 1-adamantanecarboxylic acid standard stock solution with a concentration of 1000.40 mg / L; Pipette an appropriate amount of the standard stock solution and dilute it with acetonitrile to a series of gradient concentrations of 0.80 mg / L, 1.00 mg / L, 2.00 mg / L, 4.00 mg / L, 6.00 mg / L, 8.00 mg / L, 10.0 mg / L standard working solutions.

[0057] (2) Preparation of the sample solution to be tested:

[0058] ① Soil: Weigh 10.0 g of the soil sample into a 250 mL conical flask, add 50 mL of ethanol and 0.2 mL of glacial acetic acid to the conical flask, shake for 30 min, let it stand, and take the supernatant and filter it through a 0.45 μm filter membrane to obtain the soil sample solution to be tested.

[0059] ② Water body: Absorb 15 mL of water body sample into a 100 mL conical flask, add excessive potassium chloride to saturate it, add 15 mL of acetonitrile and manually shake for 5 min. Take out the supernatant, add an appropriate amount of anhydrous sodium sulfate to remove the excess water, and filter with a 0.45 μm filter membrane to obtain the water body sample solution to be measured.

[0060] (3) Determination and calculation: Set the instrument parameters of the gas chromatograph. After the instrument is stable, absorb 1.0 μL of the standard working solution, soil sample solution, and water body sample solution prepared in steps (1) and (2) for determination, record the chromatogram, and calculate the content of 1 - adamantane carboxylic acid in the sample to be measured by the external standard method.

[0061] The operating conditions of the gas chromatograph are as follows:

[0062] Detector: FID;

[0063] Chromatographic column: HP - 5, 30 m × 0.32 mm, 0.25 μm;

[0064] Flow ratio: Pulse splitless;

[0065] Temperature: Vaporization chamber temperature 270 °C; Detector temperature 290 °C; Column oven: Initial temperature 100 °C, hold for 1 min, increase the temperature at a rate of 10 °C / min to 250 °C, hold for 0 min, increase the temperature at a rate of 50 °C / min to 300 °C, hold for 5 min;

[0066] Gas: Air: 400 mL / min; Hydrogen: 40 mL / min; Carrier gas (N2): 1.0 mL / min; Tail gas (N2): 20 mL / min.

[0067] Example 2

[0068] (1) Preparation of standard working solution: Accurately weigh 0.10105 g of 1 - adamantane carboxylic acid standard sample into a 100 mL volumetric flask, dissolve it with ethanol and make up to the mark, shake well to prepare a 1 - adamantane carboxylic acid standard stock solution with a concentration of 1000.40 mg / L; Absorb an appropriate amount of the standard stock solution and dilute it with acetonitrile to a series of gradient concentrations of 0.80 mg / L, 1.00 mg / L, 2.00 mg / L, 4.00 mg / L, 6.00 mg / L, 8.00 mg / L, 10.0 mg / L standard working solutions.

[0069] (2) Preparation of sample solution to be measured:

[0070] ① Soil: Weigh 5.0 g of soil sample into a 250 mL conical flask, add 45 mL of ethanol and 0.2 mL of glacial acetic acid to the conical flask, shake for 25 min, let it stand, and take the supernatant and filter it through a 0.45 μm filter membrane to obtain the soil sample solution to be tested.

[0071] ② Water body: Pipette 15 mL of water body sample into a 100 mL conical flask, add excessive potassium chloride to make it saturated, add 15 mL of acetonitrile and shake manually for 5 min, take out the supernatant, add an appropriate amount of anhydrous sodium sulfate to remove the excess water, and filter it through a 0.45 μm filter membrane to obtain the water body sample solution to be tested.

[0072] (3) Determination and calculation: Set the instrument parameters of the gas chromatograph. After the instrument is stable, pipette 0.5 μL of the standard working solution, soil sample solution, and water body sample solution prepared in steps (1) and (2) for determination, record the chromatogram, and calculate the content of 1 - adamantanecarboxylic acid in the sample to be tested by the external standard method.

[0073] The operating conditions of the gas chromatograph are as follows:

[0074] Detector: FID;

[0075] Chromatographic column: HP - 5, 30 m × 0.32 mm, 0.25 μm;

[0076] Flow ratio: Pulse splitless;

[0077] Temperature: Vaporization chamber temperature 260 °C; Detector temperature 280 °C; Column oven: Initial temperature 90 °C, hold for 1 min, increase the temperature at a rate of 10 °C / min to 250 °C, hold for 0 min, increase the temperature at a rate of 50 °C / min to 300 °C, hold for 5 min;

[0078] Gas: Air: 400 mL / min; Hydrogen: 40 mL / min; Carrier gas (N2): 0.5 mL / min; Tail gas blow (N2): 20 mL / min.

[0079] Example 3

[0080] (1) Preparation of the standard working solution: Weigh 0.10105 g of 1 - adamantanecarboxylic acid standard sample precisely into a 100 mL volumetric flask, dissolve it with ethanol and make up to the mark, shake well, and prepare a 1 - adamantanecarboxylic acid standard stock solution with a concentration of 1000.40 mg / L; Pipette an appropriate amount of the standard stock solution and dilute it with acetonitrile to a series of gradient concentrations of 0.80 mg / L, 1.00 mg / L, 2.00 mg / L, 4.00 mg / L, 6.00 mg / L, 8.00 mg / L, 10.0 mg / L standard working solutions.

[0081] (2) Preparation of the sample solution to be tested:

[0082] ① Soil: Weigh 8.0 g of soil sample into a 250 mL conical flask, add 48 mL of ethanol and 0.2 mL of glacial acetic acid to the conical flask, shake for 28 min, let it stand, and take the supernatant and filter it through a 0.45 μm filter membrane to obtain the soil sample solution to be measured.

[0083] ② Water body: Pipette 18 mL of water body sample into a 100 mL conical flask, add excessive potassium chloride to saturate it, add 18 mL of acetonitrile and shake manually for 8 min, take out the supernatant, add an appropriate amount of anhydrous sodium sulfate to remove the excess water, and filter it through a 0.45 μm filter membrane to obtain the water body sample solution to be measured.

[0084] (3) Determination and calculation: Set the instrument parameters of the gas chromatograph. After the instrument is stable, pipette 0.8 μL of the standard working solution, soil sample solution, and water body sample solution prepared in steps (1) and (2) for determination, record the chromatogram, and calculate the content of 1 - adamantanecarboxylic acid in the sample to be measured by the external standard method.

[0085] The operating conditions of the gas chromatograph are as follows:

[0086] Detector: FID;

[0087] Chromatographic column: HP - 5, 30 m × 0.32 mm, 0.25 μm;

[0088] Flow ratio: Pulse splitless;

[0089] Temperature: Vaporization chamber temperature 265 °C; Detector temperature 285 °C; Column oven: Initial temperature 95 °C, hold for 1 min, increase the temperature at a rate of 10 °C / min to 250 °C, hold for 0 min, increase the temperature at a rate of 50 °C / min to 300 °C, hold for 5 min;

[0090] Gas: Air: 400 mL / min; Hydrogen: 40 mL / min; Carrier gas (N2): 0.8 mL / min; Tail gas blow (N2): 20 mL / min.

[0091] Example 4

[0092] (1) Preparation of the standard working solution: Weigh 0.10105 g of 1 - adamantanecarboxylic acid standard sample accurately into a 100 mL volumetric flask, dissolve it with ethanol and make up to the mark, shake well to prepare a 1 - adamantanecarboxylic acid standard stock solution with a concentration of 1000.40 mg / L; Pipette an appropriate amount of the standard stock solution and dilute it with acetonitrile to a series of gradient concentrations of 0.80 mg / L, 1.00 mg / L, 2.00 mg / L, 4.00 mg / L, 6.00 mg / L, 8.00 mg / L, 10.0 mg / L of the standard working solution.

[0093] (2) Preparation of the sample solution to be measured:

[0094] ① Soil: Weigh 12.0 g of soil sample into a 250 mL conical flask, add 52 mL of ethanol and 0.2 mL of glacial acetic acid to the conical flask, shake for 32 min, let it stand, and filter the supernatant with a 0.45 μm filter membrane to obtain the soil sample solution to be measured.

[0095] ② Water body: Pipette 22 mL of water body sample into a 100 mL conical flask, add excessive potassium chloride to make it saturated, add 22 mL of acetonitrile and shake manually for 12 min, take out the supernatant, add an appropriate amount of anhydrous sodium sulfate to remove the excess water, and filter with a 0.45 μm filter membrane to obtain the water body sample solution to be measured.

[0096] (3) Determination and calculation: Set the instrument parameters of the gas chromatograph. After the instrument is stable, pipette 1.2 μL of the standard working solution, soil sample solution, and water body sample solution prepared in steps (1) and (2) for determination, record the chromatogram, and calculate the content of 1-adamantanecarboxylic acid in the sample to be measured by the external standard method.

[0097] The operating conditions of the gas chromatograph are as follows:

[0098] Detector: FID;

[0099] Chromatographic column: HP-5, 30 m × 0.32 mm, 0.25 μm;

[0100] Flow ratio: Pulse splitless;

[0101] Temperature: Vaporization chamber temperature 275 °C; Detector temperature 295 °C; Column oven: Initial temperature 105 °C, hold for 1 min, increase the temperature at a rate of 10 °C / min to 250 °C, hold for 0 min, increase the temperature at a rate of 50 °C / min to 300 °C, hold for 5 min;

[0102] Gas: Air: 400 mL / min; Hydrogen: 40 mL / min; Carrier gas (N2): 1.2 mL / min; Tail gas blow (N2): 20 mL / min.

[0103] Example 5

[0104] (1) Preparation of standard working solution: Weigh 0.10105 g of 1-adamantanecarboxylic acid standard sample accurately into a 100 mL volumetric flask, dissolve it with ethanol and make up to the mark, shake well to prepare a 1-adamantanecarboxylic acid standard stock solution with a concentration of 1000.40 mg / L; Pipette an appropriate amount of the standard stock solution and dilute it with acetonitrile to a series of gradient concentrations of 0.80 mg / L, 1.00 mg / L, 2.00 mg / L, 4.00 mg / L, 6.00 mg / L, 8.00 mg / L, 10.0 mg / L standard working solutions.

[0105] (2) Preparation of the sample solution to be measured:

[0106] ① Soil: Weigh 15.0 g of soil sample into a 250 mL conical flask, add 55 mL of ethanol and 0.2 mL of glacial acetic acid to the conical flask, shake for 35 min, let it stand, and take the supernatant and filter it through a 0.45 μm filter membrane to obtain the soil sample solution to be measured.

[0107] ② Water body: Pipette 25 mL of water body sample into a 100 mL conical flask, add excessive potassium chloride to saturate it, add 25 mL of acetonitrile and shake manually for 15 min, take out the supernatant, add an appropriate amount of anhydrous sodium sulfate to remove the excess water, and filter it through a 0.45 μm filter membrane to obtain the water body sample solution to be measured.

[0108] (3) Determination and calculation: Set the instrument parameters of the gas chromatograph. After the instrument is stable, pipette 1.5 μL of the standard working solution, soil sample solution, and water body sample solution prepared in steps (1) and (2) for determination, record the chromatogram, and calculate the content of 1 - adamantanecarboxylic acid in the sample to be measured by the external standard method.

[0109] The operating conditions of the gas chromatograph are as follows:

[0110] Detector: FID;

[0111] Chromatographic column: HP - 5, 30 m × 0.32 mm, 0.25 μm;

[0112] Flow ratio: Pulse splitless;

[0113] Temperature: Vaporization chamber temperature 280 °C; Detector temperature 300 °C; Column oven: Initial temperature 110 °C, hold for 1 min, increase the temperature at a rate of 10 °C / min to 250 °C, hold for 0 min, increase the temperature at a rate of 50 °C / min to 300 °C, hold for 5 min;

[0114] Gas: Air: 400 mL / min; Hydrogen: 40 mL / min; Carrier gas (N2): 1.5 mL / min; Tail gas blow (N2): 20 mL / min.

[0115] The following is the methodological verification test of the present invention:

[0116] 1. Specificity test

[0117] Measure the water body blank sample, water body spiked recovery sample, soil blank sample, and soil spiked recovery sample under the instrument operating conditions of the present invention, compare the chromatograms of the water body and soil blank samples and spiked recovery samples. 1 - adamantanecarboxylic acid elutes at 7.5 min, and there is no interference peak at this time point in the blank sample. The results show that the method has good specificity for 1 - adamantanecarboxylic acid.

[0118] 2. Linearity test

[0119] The standard working solutions of 1-adamantanecarboxylic acid series with concentrations of 0.80 mg / L, 1.00 mg / L, 2.00 mg / L, 4.00 mg / L, 6.00 mg / L, 8.00 mg / L, and 10.0 mg / L in the examples were determined under the instrument operating conditions of the present invention. The average values of the results of injecting 3 needles of each working solution were used for linear relationship fitting, and the analysis results are shown in Table 1.

[0120] The test results show that: when the concentration of 1-adamantanecarboxylic acid is in the range of 0.80 mg / L to 10.0 mg / L, there is a linear relationship between y and x. The linear regression equation is y = 8.5952x - 4.8097, and the linear correlation coefficient R 2 = 0.9987. The linear fitting curve is shown in Figure 1 .

[0121] Table 1: Analysis results of linear test

[0122]

[0123] 3. Repeatability test

[0124] The standard working solution with a 1-adamantanecarboxylic acid concentration of 4.00 mg / L in the example was selected for the method repeatability test, and the sample was injected 6 times repeatedly. The results are shown in Table 2. Figure 3 .

[0125] The results show that: the RSD R.T. is 0.01%, and the RSD Area is 4.97%, both of which are less than 5.00%. This indicates that this method can be used for the qualitative and quantitative analysis of 1-adamantanecarboxylic acid.

[0126] Table 2: Results of repeatability test

[0127]

[0128]

[0129] 4. Detection limit and quantification limit

[0130] The standard stock solution with a 1-adamantanecarboxylic acid concentration of 1000.40 mg / L in the example was taken and diluted with acetonitrile to prepare a standard working solution with a concentration of 0.40 mg / L for the detection limit test. The standard working solution with a 1-adamantanecarboxylic acid concentration of 1.00 mg / L in Example 1 was taken for the quantification limit test. The sample was injected 3 times repeatedly, and the LOD and LOQ were calculated from S / N, and the average results were analyzed. The results are shown in Table 3. Figure 4 . Figure 5。The LOD of this method for 1 - adamantane carboxylic acid is 0.10 mg / L, and the LOQ is 0.22 mg / L.

[0131] Table 3: Detection Limit and Quantification Limit of 1 - adamantane carboxylic acid

[0132] Number of measurements Analytical concentration (mg / L) S / N LOD (mg / L) LOQ (mg / L) 1 0.40 15.34 0.08 - 2 0.40 11.95 0.10 - 3 0.40 10.87 0.11 - 1 1.00 48.88 - 0.20 2 1.00 41.93 - 0.24 3 1.00 43.77 - 0.23 Average value - - 0.10 0.22

[0133] 5. Sample Spike Recovery Test

[0134] 5.1 Soil Sample Spike Recovery Test

[0135] Weigh 10.0 g of paddy soil into two 250 mL conical flasks respectively, add 0.50 mL of standard working solutions of 1 - adamantane carboxylic acid with concentrations of 100.0 mg / L and 1000.4 mg / L respectively, mix well to prepare two soil recovery samples with concentrations of 5.00 mg / kg and 50.0 mg / kg respectively. Add 50 mL of ethanol and 0.2 mL of glacial acetic acid to the above - mentioned conical flasks, shake for 30 min, let it stand, and then take the supernatant and filter it through a 0.45 μm filter membrane for standby (dilute the high - concentration sample 2 times with acetonitrile). Make 5 parallel samples for each concentration sample, and at the same time, conduct a soil blank test, and determine the concentration of 1 - adamantane carboxylic acid according to the instrument operation conditions of the present invention.

[0136] The analysis results are shown in Table 4 Figure 6 、 Figure 7 、 Figure 8 , The average spike recoveries of 1 - adamantane carboxylic acid at two different concentrations in soil are 92.2% and 105.2% respectively, and the standard deviations of recoveries are 6.1% and 4.9% respectively.

[0137] Table 4: Results of Spike Recovery of 1 - adamantane carboxylic acid at Different Concentrations in Soil

[0138]

[0139] 5.2 Water Sample Spike Recovery Test

[0140] Take 1.00 mL of working solutions of 1 - adamantane carboxylic acid with concentrations of 100.0 mg / L and 1000.4 mg / L respectively into two 100 mL volumetric flasks, and make up the volume with UP water to obtain water recovery samples of 1 - adamantane carboxylic acid with concentrations of 1.00 mg / L and 10.0 mg / L respectively. Take 20 mL of the water recovery sample into a 100 mL conical flask, add excessive potassium chloride to saturate it, add 20 mL of acetonitrile and manually shake for 10 min, take out the supernatant, add an appropriate amount of anhydrous sodium sulfate to remove the excess water, and filter it through a 0.45 μm filter membrane (dilute the high - concentration sample 2 times with acetonitrile). Make 5 parallel samples for each concentration sample, and at the same time, conduct a water blank test, and determine the concentration of 1 - adamantane carboxylic acid according to the instrument operation conditions of the present invention.

[0141] The analysis results are shown in Table 5, Figure 9 , Figure 10 , Figure 11 , and the average spiked recoveries of 1-adamantanecarboxylic acid at two different concentrations in water are 101.5% and 100.3% respectively, and the standard deviations of the recoveries are 5.7% and 5.1% respectively.

[0142] Table 5: Results of spiked recoveries of 1-adamantanecarboxylic acid at different concentrations in water

[0143]

[0144]

Claims

1. A method for detecting the content of 1-adamantanecarboxylic acid in soil and water by gas chromatography, characterized in that, The method steps are as follows: (1) Preparation of standard working solution: Accurately weigh 0.10105 g of 1-adamantanecarboxylic acid standard sample into a 100 mL volumetric flask, dissolve it with ethanol and make up to the mark, shake well to prepare a 1-adamantanecarboxylic acid standard stock solution with a concentration of 1000.40 mg / L; Pipette an appropriate amount of the standard stock solution and dilute it with acetonitrile to obtain a series of gradient concentration standard working solutions; (2) Preparation of test sample solution: Soil: Collect the soil sample to be tested, and use it after pretreatment such as impurity removal, air drying, and sieving. Weigh 5.0 - 15.0 g of the pretreated soil sample into a 250 mL conical flask, add 45 - 55 mL of ethanol and 0.2 mL of glacial acetic acid to the conical flask, shake for 25 - 35 min, let it stand, and take the supernatant and filter it through a 0.45 µm filter membrane to obtain the soil sample solution to be tested; Water body: Pipette 15 - 25 mL of the water body sample into a 100 mL conical flask, add excessive potassium chloride to saturate it, add 15 - 25 mL of acetonitrile and manually shake for 5 - 15 min, take out the supernatant, add an appropriate amount of anhydrous sodium sulfate to remove the excess water, and filter it through a 0.45 µm filter membrane to obtain the water body sample solution to be tested; (3) Determination and calculation: Set the instrument parameters of the gas chromatograph. After the instrument is stable, pipette 0.5 - 1.5 μL of the standard working solution, soil sample solution, and water body sample solution prepared in steps (1) and (2) for determination, record the chromatogram, and calculate the content of 1-adamantanecarboxylic acid in the test sample by the external standard method; In step (1), the concentrations of the series of gradient concentration standard working solutions are 0.80 mg / L, 1.00 mg / L, 2.00 mg / L, 4.00 mg / L, 6.00 mg / L, 8.00 mg / L, and 10.0 mg / L respectively; The instrument operating conditions of the gas chromatograph are as follows: Detector: FID; Chromatographic column: HP-5, 30 m × 0.32 mm, 0.25 µm; Flow ratio: Pulse splitless; Temperature: Vaporization chamber temperature 260 - 280 °C; Detector temperature 280 - 300 °C; Column oven: Initial temperature 90 - 110 °C, hold for 1 min, heat at a rate of 10 °C / min to 250 °C, hold for 0 min, heat at a rate of 50 °C / min to 300 °C, hold for 5 min; Gas: Air: 400 mL / min; Hydrogen: 40 mL / min; Carrier gas N2: 0.5 - 1.5 mL / min; Tail gas blow N2: 20 mL / min.

2. The method according to claim 1, characterized in that, The method steps are as follows: (1) Preparation of standard working solution: Accurately weigh 0.10105 g of 1-adamantanecarboxylic acid standard sample into a 100 mL volumetric flask, dissolve it with ethanol and make up to the mark, shake well to prepare a 1-adamantanecarboxylic acid standard stock solution with a concentration of 1000.40 mg / L; Pipette an appropriate amount of the standard stock solution and dilute it with acetonitrile to obtain a series of gradient concentration standard working solutions; (2) Preparation of test sample solution: Soil: Collect the soil samples to be tested. After pretreatment of impurity removal, air drying, and sieving, they are reserved for use. Weigh 8.0 - 12.0 g of the pretreated soil samples into a 250 mL conical flask, add 48 - 52 mL of ethanol and 0.2 mL of glacial acetic acid to the conical flask, oscillate for 28 - 32 min, let it stand, and take the supernatant and filter it through a 0.45 µm filter membrane to obtain the soil sample solution to be tested; Water body: Pipette 18 - 22 mL of the water body sample into a 100 mL conical flask, add excessive potassium chloride to saturate it, add 18 - 22 mL of acetonitrile and manually oscillate for 8 - 12 min, take out the supernatant, add an appropriate amount of anhydrous sodium sulfate to remove the excess water, and filter it through a 0.45 µm filter membrane to obtain the water body sample solution to be tested; (3) Determination and calculation: Set the instrument parameters of the gas chromatograph. After the instrument is stable, pipette 0.8 - 1.2 μL of the standard working solution, soil sample solution, and water body sample solution prepared in steps (1) and (2) for determination, record the chromatogram, and calculate the content of 1 - adamantanecarboxylic acid in the sample to be tested by the external standard method.

3. The method according to claim 2, wherein The steps of the method are as follows: (1) Preparation of the standard working solution: Weigh 0.10105 g of 1 - adamantanecarboxylic acid standard sample accurately into a 100 mL volumetric flask, dissolve it with ethanol and make up to the scale, shake well, and prepare a 1 - adamantanecarboxylic acid standard stock solution with a concentration of 1000.40 mg / L; Pipette an appropriate amount of the standard stock solution and dilute it with acetonitrile to obtain a series of gradient concentration standard working solutions; (2) Preparation of the sample solution to be tested: Soil: Collect the soil samples to be tested. After pretreatment of impurity removal, air drying, and sieving, they are reserved for use. Weigh 10.0 g of the pretreated soil samples into a 250 mL conical flask, add 50 mL of ethanol and 0.2 mL of glacial acetic acid to the conical flask, oscillate for 30 min, let it stand, and take the supernatant and filter it through a 0.45 µm filter membrane to obtain the soil sample solution to be tested; Water body: Pipette 20 mL of the water body sample into a 100 mL conical flask, add excessive potassium chloride to saturate it, add 20 mL of acetonitrile and manually oscillate for 10 min, take out the supernatant, add an appropriate amount of anhydrous sodium sulfate to remove the excess water, and filter it through a 0.45 µm filter membrane to obtain the water body sample solution to be tested; (3) Determination and calculation: Set the instrument parameters of the gas chromatograph. After the instrument is stable, pipette 1.0 μL of the standard working solution, soil sample solution, and water body sample solution prepared in steps (1) and (2) for determination, record the chromatogram, and calculate the content of 1 - adamantanecarboxylic acid in the sample to be tested by the external standard method.

4. The method according to claim 1, wherein The vaporization chamber temperature is 265 - 275 °C, the detector temperature is 285 - 295 °C, and the initial column oven temperature is 95 - 105 °C.

5. The method according to claim 4, characterized in that The vaporization chamber temperature is 270 °C, the detector temperature is 290 °C, and the initial column oven temperature is 100 °C.

6. The method according to claim 1, wherein The flow rate of the carrier gas N2 is 0.8 - 1.2 mL / min.

7. The method according to claim 6, wherein The flow rate of the carrier gas N2 is 1.0 mL / min.

8. The method according to claim 1, characterized in that, The LOD of the method for 1 - adamantanecarboxylic acid is 0.10 mg / L, and the LOQ is 0.22 mg / L.

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