Method for measuring content of hexadecyl chloroformate

Abstract

The invention provides a method for determining the content of hexadecyl chloroformate. The method comprises the following steps: dissolving a hexadecyl chloroformate standard substance with 1.2-dichloroethane, determining the content by using reversed-phase high performance liquid chromatography with methanol as a mobile phase, and establishing a linear relation curve; and dissolving a to-be-detected sample with 1.2-dichloroethane, determining the content by using reversed-phase high performance liquid chromatography, and substituting the obtained chromatographic response value into the linear relation curve to obtain the content of the hexadecyl chloroformate in the to-be-detected sample. The method adopts specific chromatographic conditions to realize stable and accurate detection of hexadecyl chloroformate, meets the requirements of quality control and scientific research in industrial production, simplifies the preparation steps of a contrast solution and a sample solution, is simple and convenient to operate, high in sensitivity, accurate, reliable and low in cost, can meet the actual determination requirements, and has a wide application prospect. And the blank of related problems about content determination of the hexadecyl chloroformate in the prior art is filled.

Description

Technical Field

[0001] The invention relates to the technical field of analysis and detection, and in particular to a method for determining the content of hexadecyl chloroformate. Background Art

[0002] Hexadecyl chloroformate is an organic compound with a wide range of uses. In the industrial field, it can be used as a solvent and is widely used in the production of coatings, inks, adhesives, detergents, dyes and cosmetics. It can also be used as a surfactant, solubilizer and wetting agent. In addition, hexadecyl chloroformate is also used in foreign trade exports, scientific research and chemical reagents.

[0003] In the production and use of chemical products, accurate determination of the content of its ingredients is crucial for product quality control and safety evaluation. However, there is a gap in the literature and industry standards for the determination of the content of hexadecyl chloroformate. There is a lack of a stable, accurate and efficient detection technology. In the process of preparing hexadecyl chloroformate, it is impossible to track the content of hexadecyl chloroformate in intermediates and products.

[0004] Traditional detection methods, such as gas chromatography, thin layer chromatography, etc., often have problems such as complex operation, high detection limit, poor selectivity, etc., and are difficult to meet the demand for high-precision determination of hexadecyl chloroformate content. In particular, hexadecyl chloroformate has poor solubility in certain solvents, tailing peak shape, and unstable response value, which greatly reduces the accuracy of traditional detection methods. In addition, the selection of mobile phase in the prior art has not fully considered the characteristics of hexadecyl chloroformate, resulting in poor separation effect during the detection process, unsatisfactory peak shape, and affects the accuracy of content determination. Summary of the invention

[0005] The main purpose of the present invention is to provide a method for determining the content of hexadecyl chloroformate, so as to solve the problem that it is difficult to accurately determine the content of hexadecyl chloroformate in the prior art.

[0006] In order to achieve the above-mentioned object, according to one aspect of the present invention, a method for determining the content of hexadecyl chloroformate is provided, comprising the following steps: step S1, dissolving a hexadecyl chloroformate standard in 1.2-dichloroethane to obtain a series of control solutions; performing content determination on the series of control solutions by reversed-phase high performance liquid chromatography, taking the mass concentration of hexadecyl chloroformate in the series of control solutions as the abscissa and the chromatographic response value of the series of control solutions as the ordinate, and establishing a linear relationship curve; step S2, dissolving a sample to be tested in 1.2-dichloroethane to obtain a sample solution; performing content determination on the sample solution by reversed-phase high performance liquid chromatography to obtain the chromatographic response value of the sample solution, substituting it into the linear relationship curve to obtain the content of hexadecyl chloroformate in the sample to be tested; wherein the mobile phase of the reversed-phase high performance liquid chromatography is methanol.

[0007] Furthermore, the filler of the chromatographic column of the reversed-phase high performance liquid chromatography is C18 or C8.

[0008] Furthermore, the size of the chromatographic column of the reversed-phase high performance liquid chromatography is 250 mm×4.6 mm or 150 mm×4.6 mm.

[0009] Furthermore, the flow rate of the mobile phase is 0.8 to 1.2 mL / min.

[0010] Furthermore, the detection wavelength of the reversed-phase high performance liquid chromatography is 195 to 230 nm.

[0011] Furthermore, the injection volume of the reverse phase high performance liquid chromatography is 3 to 10 μL.

[0012] Furthermore, the column temperature of the reverse phase HPLC is 25-35°C.

[0013] Furthermore, the series of control solutions include at least 6 control solutions of different concentrations, wherein the mass concentrations of hexadecyl chloroformate are 0.0200 g / mL, 0.0410 g / mL, 0.0802 g / mL, 0.1160 g / mL, 0.1522 g / mL, and 0.1803 g / mL, respectively.

[0014] Furthermore, the mass concentration of the sample solution is 0.03-0.05 g / mL.

[0015] Further, in step S2, the content X1 of hexadecyl chloroformate in the sample to be tested is calculated by formula (1):

[0016]

[0017] Wherein: A1 is the average peak area of ​​the control solution; A2 is the peak area of ​​the sample solution; W1 is the average sample weight of the control solution, in g; W2 is the sample weight of the sample solution, in g; P is the average content of hexadecyl chloroformate in the control solution, in %.

[0018] The present invention is a method for accurately determining the content of hexadecyl chloroformate by reversed-phase high performance liquid chromatography, using methanol as a mobile phase and 1,2-dichloroethane as a solvent. Applying the technical scheme of the present invention, using 1.2-dichloroethane as a solvent and 100% methanol as a mobile phase, a liquid chromatography external standard method (external standard curve method) is established to quantitatively analyze hexadecyl chloroformate in a sample, with stable data and accurate results. The linear relationship curve established by the present invention provides a reliable basis for content calculation, making the measurement results more accurate and reliable; using specific chromatographic conditions to achieve stable and accurate detection of hexadecyl chloroformate, the precision and relative range are not more than 0.7%, and the average recovery rate can reach 98%, meeting the needs of quality control and scientific research in industrial production. In addition, the present invention simplifies the preparation steps of the control solution and the sample solution, improves the operability and efficiency of the experiment, and can effectively improve the accuracy and speed of the determination of the content of hexadecyl chloroformate. The determination method of the invention is simple to operate, highly sensitive, accurate and reliable, and low in cost, can meet actual determination needs, and fills the gap in the prior art and literature on the determination of hexadecyl chloroformate content. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0020] Figure 1 shows a linear relationship curve according to an embodiment of the present invention;

[0021] Figure 2 shows a reverse phase high performance liquid chromatogram of a sample solution according to an embodiment of the present invention;

[0022] Figure 3 A reverse phase high performance liquid chromatogram of the sample solution according to Comparative Example 1 is shown. DETAILED DESCRIPTION

[0023] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0024] As described in the background of the present invention, there is a problem in the prior art that it is difficult to accurately determine the content of hexadecyl chloroformate. In order to solve the above problems, in a typical embodiment of the present invention, a method for determining the content of hexadecyl chloroformate is provided, comprising the following steps: step S1, dissolving the hexadecyl chloroformate standard with 1.2-dichloroethane to obtain a series of control solutions; using reversed-phase high performance liquid chromatography to determine the content of the series of control solutions, using the mass concentration of hexadecyl chloroformate in the series of control solutions as the horizontal coordinate, and the chromatographic response value of the series of control solutions as the vertical coordinate, to establish a linear relationship curve; step S2, dissolving the sample to be tested with 1.2-dichloroethane to obtain a sample solution; using reversed-phase high performance liquid chromatography to determine the content of the sample solution, obtaining the chromatographic response value of the sample solution, substituting it into the linear relationship curve, and obtaining the content of hexadecyl chloroformate in the sample to be tested; wherein, the mobile phase of the reversed-phase high performance liquid chromatography is methanol.

[0025] The invention firstly dissolves a hexadecyl chloroformate standard with 1.2-dichloroethane to obtain a series of control solutions; and dissolves a sample to be tested with 1.2-dichloroethane to obtain a sample solution. The inventor unexpectedly found in the research process that when conventional solvents such as benzene or chlorobenzene are used as sample preparation solvents, the peak shape is not a symmetrical sharp peak and has severe tailing, and even affects the peak of hexadecyl chloroformate; when ethanol is used as the sample preparation solvent, the response is poor and the peak shape is not symmetrical and sharp enough; when 1.2-dichloroethane is used as the solvent for dissolving the sample, the solubility and stability of the sample to be tested can be improved, the solvent peak tailing is light, and the peak of hexadecyl chloroformate will not be affected, the chromatographic response is good, the peak shape is symmetrical and sharp, and accurate quantification is convenient.

[0026] Then the series of control solutions are respectively measured using reversed-phase high performance liquid chromatography, with the mass concentration of hexadecyl chloroformate in the series of control solutions as the horizontal coordinate, and the chromatographic response value of the series of control solutions as the vertical coordinate, to establish a linear relationship curve, wherein the mobile phase of the reversed-phase high performance liquid chromatography is methanol. The inventor unexpectedly found in the research process that when conventional acetonitrile is used as the mobile phase, the peak shape is extremely poor and the tailing is serious; when methanol and water are used as the mobile phase, the baseline drifts slightly, the peak shape is poor and the peak is late; and 100% methanol is used as the mobile phase, which has good solubility and elution ability, can effectively improve the sensitivity and selectivity of the detection, can achieve effective separation and accurate detection of hexadecyl chloroformate, and the peak shape is better, the tailing is lighter, the baseline will not drift, the peak time is faster, and the determination time can be significantly shortened on the basis of accurate quantification. The linear relationship curve established by the present invention provides a reliable basis for content calculation, so that the determination result is more accurate and reliable.

[0027] Finally, the sample solution is subjected to content determination using reversed-phase high-performance liquid chromatography to obtain the chromatographic response value of the sample solution, which is substituted into the linear relationship curve to obtain the content of hexadecyl chloroformate in the sample to be tested. The present invention dissolves the sample to be tested in 1.2-dichloroethane, uses methanol as a mobile phase, performs reversed-phase high-performance liquid chromatography separation on the hexadecyl chloroformate in the sample, and according to the curve relationship between the response value and the concentration of the hexadecyl chloroformate on the chromatogram, the concentration of the sample is determined by a liquid chromatography external standard quantitative method, and specific chromatographic conditions are used to achieve stable and accurate detection of hexadecyl chloroformate, the precision and relative range are both no more than 0.7%, and the average recovery rate can reach 98%, meeting the needs of quality control and scientific research in industrial production.

[0028] The present invention proposes a novel detection technology based on reversed-phase high performance liquid chromatography, which aims to fill the gap in the prior art, provide a more ideal hexadecyl chloroformate content determination scheme, and realize accurate detection of hexadecyl chloroformate content. The present invention is simple to operate, and can quickly feedback results; high sensitivity, can detect low-content hexadecyl chloroformate; high accuracy, can provide stable and repeatable measurement results; low cost, suitable for mass production and quality control in daily scientific research. In summary, the present invention uses 1.2-dichloroethane as a solvent and 100% methanol as a mobile phase, and establishes a method for quantitative analysis of hexadecyl chloroformate in a sample by a liquid chromatography external standard method (external standard curve method), and the data is stable and the results are accurate. In addition, the present invention simplifies the preparation steps of the control solution and the sample solution, improves the operability and efficiency of the experiment, and can effectively improve the accuracy and speed of the determination of the hexadecyl chloroformate content.

[0029] The present invention further improves the sensitivity and accuracy of detection by controlling parameters such as chromatographic column, flow rate, detection wavelength, injection volume, etc.

[0030] In a preferred embodiment, the filler of the chromatographic column of the reversed-phase high performance liquid chromatography is C18 or C8. The chromatographic column with the above filler has higher separation, better symmetry, and no tailing of the peak shape, and can better achieve effective separation and accurate detection of hexadecyl chloroformate.

[0031] In order to provide sufficient separation and ensure faster analysis speed, in a preferred embodiment, the size of the chromatographic column of the reversed-phase high performance liquid chromatography is 250 mm×4.6 mm or 150 mm×4.6 mm (length×diameter). Most preferably, the chromatographic column is a 250 mm×4.6 mm C18 stainless steel column, which can provide more stable chromatographic performance and longer service life.

[0032] In a preferred embodiment, the flow rate of the mobile phase is 0.8-1.2 mL / min, which can speed up the peak elution rate while better avoiding the peak elution from being close to impurities. In this case, the analysis time is about 10-15 minutes, the analysis efficiency is higher, and the results can be fed back quickly.

[0033] In order to better achieve specific detection of hexadecyl chloroformate, in a preferred embodiment, the detection wavelength of the reversed-phase high performance liquid chromatography is 195 to 230 nm. Hexadecyl chloroformate has a stronger absorption peak and response value within the above wavelength range, which can further improve the sensitivity of detection, and is most preferably 204 nm.

[0034] In a preferred embodiment, the injection volume of the reversed-phase high performance liquid chromatography is 3 to 10 μL, which can improve the detection accuracy and reduce the waste of samples.

[0035] Controlling the column temperature can optimize the separation effect of the compounds and further reduce the tailing phenomenon. In a preferred embodiment, the column temperature of the reversed-phase HPLC is 25 to 35° C., which can further improve the repeatability and stability of the detection.

[0036] In a preferred embodiment, the series of control solutions include at least 6 control solutions of different concentrations, wherein the mass concentrations of hexadecyl chloroformate are 0.0200 g / mL, 0.0410 g / mL, 0.0802 g / mL, 0.1160 g / mL, 0.1522 g / mL, and 0.1803 g / mL, respectively. The linear relationship curve established by the above series of standard samples can better ensure the accuracy and reliability of content calculation, and can further eliminate systematic errors and improve the accuracy and credibility of data.

[0037] The preparation steps and requirements of the sample solution and the control solution are the same, which can improve the consistency and comparability of the experiment. In a preferred embodiment, the mass concentration of the sample solution is 0.03-0.05 g / mL.

[0038] As described above, the present invention uses reverse phase high performance liquid chromatography to measure the content of the sample solution, obtains the sample chromatographic response value, substitutes it into the linear relationship curve, and obtains the content of hexadecyl chloroformate in the sample to be tested by the external standard method. Specifically, in a preferred embodiment, in step S2, the content X1 of hexadecyl chloroformate in the sample to be tested is calculated by formula (1):

[0039]

[0040] In the formula: A1 is the peak area of ​​any reference solution; A2 is the peak area of ​​the sample solution; W1 is the sample weight of the reference solution corresponding to A1, in g; W2 is the sample weight of the sample solution, in g; P is the content of hexadecyl chloroformate in the reference solution corresponding to A1, in %.

[0041] The present application is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present application.

[0042] In the following examples and comparative examples, the reagents and instruments are as follows:

[0043] High performance liquid chromatograph: Agilent LC1220 with variable wavelength UV detector; Chromatographic workstation: EZchromElite;

[0044] Micro-injector: automatic sampler 100μL;

[0045] Hexadecyl chloroformate standard (referred to as standard sample): a sample with known content purchased from outside, with a content greater than or equal to 98.0%;

[0046] Sample to be tested (referred to as sample): homemade;

[0047] Methanol: chromatographic grade;

[0048] 1.2-Dichloroethane: analytical grade.

[0049] Example 1

[0050]

Chromatographic conditions

[0051] Chromatographic column: 250mm×4.6mm, C18 stainless steel column;

[0052] Mobile phase: 100% methanol;

[0053] Mobile phase flow rate: 1.0 mL / min;

[0054] Column temperature: 30°C;

[0055] Detection wavelength: 204nm;

[0056] Injection volume: 5 μL;

[0057] Analysis time: 12 minutes.

[0058]

Measurement steps

[0059] Step S1, weigh 0.50g (accurate to 0.0001g), 1.00g (accurate to 0.0001g), 2.00g (accurate to 0.0001g), 3.00g (accurate to 0.0001g), 4.00g (accurate to 0.0001g), 4.50g (accurate to 0.0001g) of hexadecyl chloroformate standard in 6 25ml volumetric flasks, dissolve and dilute to the mark with 1.2-dichloroethane, shake well for use, and obtain a series of control solutions. The series of control solutions were respectively determined by reversed-phase high performance liquid chromatography, and the results are shown in Table 1; the mass concentration of hexadecyl chloroformate in the series of control solutions was used as the horizontal coordinate, and the chromatographic response value of the series of control solutions was used as the vertical coordinate to establish a linear relationship curve, see Figure 1 ;

[0060] Step S2, weigh 1.0 g (accurate to 0.0002 g) of hexadecyl chloroformate to be tested in a 25 ml volumetric flask, dissolve it with 1.2-dichloroethane and dilute to the mark, shake well for later use, and obtain a sample solution with a mass concentration of 0.04 g / mL; the sample solution is subjected to content determination using reversed-phase high performance liquid chromatography to obtain a sample chromatographic response value, substitute it into the linear relationship curve, and calculate the content X1 of hexadecyl chloroformate in the sample to be tested by formula (1):

[0061]

[0062] Wherein: A1 is the average peak area of ​​the control solution; A2 is the peak area of ​​the sample solution; W1 is the average sample weight of the control solution, in g; W2 is the sample weight of the sample solution, in g; P is the average content of hexadecyl chloroformate in the control solution, in %.

[0063] Three batches of hexadecyl chloroformate samples were taken for testing, and each batch of samples was tested 4 times. The results are shown in Table 2.

[0064] A typical reverse phase HPLC chromatogram of a sample solution is shown in Figure 2 .

[0065] Table 1

[0066] / Sample weight g Hexadecyl chloroformate concentration g / mL Peak area Control solution 1 0.5011 0.0200 18246077 Control solution 2 1.0259 0.0410 37356880 Control solution 3 2.0039 0.0802 72966248 Control solution 4 2.9008 0.1160 102558552 Control solution 5 3.8045 0.1522 135023287 Control solution 6 4.5080 0.1803 160506714

[0067] Table 2

[0068] batch number Content 1% Content 2% Content 3% Content 4% average value% Relative range % RSD% 1# 94.75 94.78 94.69 94.81 94.76 0.13 0.05 2# 96.44 96.28 96.47 96.35 96.38 0.20 0.09 3# 98.55 98.63 98.48 98.57 98.56 0.15 0.06

[0069]

Recovery rate experiment

[0070] Step 1, accurately weigh 2.0000g (accurate to 0.0001g) of hexadecyl chloroformate standard in two 25mL volumetric flasks, dissolve and dilute to the mark with 1.2-dichloroethane, shake well for use. Named as No. 1 and No. 2. The above solutions are respectively determined by reverse phase high performance liquid chromatography (automatic injection after the instrument is stable), and the results are shown in Table 3.

[0071] Step 2, accurately weigh 1.0000g (accurate to 0.0001g) hexadecyl chloroformate sample to be tested and 1.0000g (accurate to 0.0001g) hexadecyl chloroformate standard in the same 25mL volumetric flask, dissolve and dilute to the mark with 1.2-dichloroethane, shake up for standby use, prepare 3 parts in parallel. Named as sample 1#, sample 2#, sample 3#. The above solutions are respectively assayed using reversed-phase high performance liquid chromatography (after the instrument is stable, automatic injection), and the chromatographic response values ​​of the three samples are obtained, as shown in Table 3.

[0072] Step 3, calculate the recovery rate: the contents of the three batches of test samples were calibrated with the average value of the hexadecyl chloroformate standard to correct the added mass of the standard sample, and the average recovery rate was 98.78%. The calculation formula is shown in Table 3.

[0073] Table 3

[0074]

[0075] From the above, we can know that when the concentration of hexadecyl chloroformate is in the range of 0.0200 to 0.1803 g / mL, the linear formula is y=882605623.37X+1030870.32, R 2 =1.00, indicating that the linear relationship between the mass concentration of hexadecyl chloroformate and the chromatographic response value is good; the precision and relative range of the hexadecyl chloroformate sample determination are both no more than 0.5%, indicating that the method has good precision; the average recovery rate of the method is 98.78%, indicating that the accuracy of the method is high. In summary, the determination method of the hexadecyl chloroformate content of the present invention meets the inspection requirements.

[0076] Example 2

[0077] The difference from Example 1 is that the chromatographic conditions are different:

[0078] Chromatographic column: 150mm×4.6mm, C18 stainless steel column;

[0079] Mobile phase: 100% methanol;

[0080] Mobile phase flow rate: 0.8 mL / min;

[0081] Column temperature: 25°C;

[0082] Detection wavelength: 195nm;

[0083] Injection volume: 3 μL;

[0084] Analysis time: 12 minutes.

[0085]

Measurement steps

[0086] Step S1, weigh 0.50g (accurate to 0.0001g), 1.00g (accurate to 0.0001g), 2.00g (accurate to 0.0001g), 3.00g (accurate to 0.0001g), 4.00g (accurate to 0.0001g), 4.50g (accurate to 0.0001g) of hexadecyl chloroformate standard into 6 25ml volumetric flasks, dissolve and dilute to the mark with 1.2-dichloroethane, shake well for standby use, and obtain a series of control solutions. The series of control solutions are respectively measured by reversed-phase high performance liquid chromatography, and the linear results and linear relationship curves are the same as those in Example 1;

[0087] Step S2, weigh 1.0 g (accurate to 0.0002 g) of hexadecyl chloroformate to be tested in a 25 ml volumetric flask, dissolve it with 1.2-dichloroethane and dilute to the mark, shake well for later use, and obtain a sample solution with a mass concentration of 0.04 g / mL; the sample solution is subjected to content determination using reversed-phase high performance liquid chromatography to obtain a sample chromatographic response value, substitute it into the linear relationship curve, and calculate the content X1 of hexadecyl chloroformate in the sample to be tested by formula (1):

[0088]

[0089] Wherein: A1 is the average peak area of ​​the control solution; A2 is the peak area of ​​the sample solution; W1 is the average sample weight of the control solution, in g; W2 is the sample weight of the sample solution, in g; P is the average content of hexadecyl chloroformate in the control solution, in %.

[0090] Take the hexadecyl chloroformate sample to be tested from batch 1# and repeat the measurement 4 times. The average content of hexadecyl chloroformate measured is shown in Table 4.

[0091] Example 3

[0092] The difference from Example 1 is that the chromatographic conditions are different:

[0093] Chromatographic column: 250mm×4.6mm, C8 stainless steel column;

[0094] Mobile phase: 100% methanol;

[0095] Mobile phase flow rate: 1.2 mL / min;

[0096] Column temperature: 35 °C;

[0097] Detection wavelength: 230nm;

[0098] Injection volume: 10 μL;

[0099] Analysis time: 12 minutes.

[0100]

Measurement steps

[0101] Step S1, weigh 0.50g (accurate to 0.0001g), 1.00g (accurate to 0.0001g), 2.00g (accurate to 0.0001g), 3.00g (accurate to 0.0001g), 4.00g (accurate to 0.0001g), 4.50g (accurate to 0.0001g) of hexadecyl chloroformate standard into 6 25ml volumetric flasks, dissolve and dilute to the mark with 1.2-dichloroethane, shake well for standby use, and obtain a series of control solutions. The series of control solutions are respectively measured by reversed-phase high performance liquid chromatography, and the linear results and linear relationship curves are the same as those in Example 1;

[0102] Step S2, weigh 1.0 g (accurate to 0.0002 g) of hexadecyl chloroformate to be tested in a 25 ml volumetric flask, dissolve it with 1.2-dichloroethane and dilute to the mark, shake well for later use, and obtain a sample solution with a mass concentration of 0.04 g / mL; the sample solution is subjected to content determination using reversed-phase high performance liquid chromatography to obtain a sample chromatographic response value, substitute it into the linear relationship curve, and calculate the content X1 of hexadecyl chloroformate in the sample to be tested by formula (1):

[0103]

[0104] Wherein: A1 is the average peak area of ​​the control solution; A2 is the peak area of ​​the sample solution; W1 is the average sample weight of the control solution, in g; W2 is the sample weight of the sample solution, in g; P is the average content of hexadecyl chloroformate in the control solution, in %.

[0105] Take the hexadecyl chloroformate sample to be tested from batch 1# and repeat the measurement 4 times. The average content of hexadecyl chloroformate measured is shown in Table 4.

[0106] Example 4

[0107] The difference from Example 1 is that the mass concentration of the sample solution is different:

[0108]

Chromatographic conditions

[0109] Chromatographic column: 250mm×4.6mm, C18 stainless steel column;

[0110] Mobile phase: 100% methanol;

[0111] Mobile phase flow rate: 1.0 mL / min;

[0112] Column temperature: 30°C;

[0113] Detection wavelength: 204nm;

[0114] Injection volume: 5 μL;

[0115] Analysis time: 12 minutes.

[0116]

Measurement steps

[0117] Step S1, weigh 0.50g (accurate to 0.0001g), 1.00g (accurate to 0.0001g), 2.00g (accurate to 0.0001g), 3.00g (accurate to 0.0001g), 4.00g (accurate to 0.0001g), 4.50g (accurate to 0.0001g) of hexadecyl chloroformate standard into 6 25ml volumetric flasks, dissolve and dilute to the mark with 1.2-dichloroethane, shake well for standby use, and obtain a series of control solutions. The series of control solutions are respectively measured by reversed-phase high performance liquid chromatography, and the linear results and linear relationship curves are the same as those in Example 1;

[0118] Step S2, weigh 0.75g (accurate to 0.0002g) of hexadecyl chloroformate sample to be tested (batch 1#) into a 25ml volumetric flask, dilute to the mark with 1.2-dichloroethane, shake well for standby use, and obtain a sample solution with a mass concentration of 0.03g / mL; the sample solution is subjected to content determination using reversed-phase high performance liquid chromatography to obtain a sample chromatographic response value, which is substituted into the linear relationship curve, and the content X1 of hexadecyl chloroformate in the sample to be tested is calculated by formula (1):

[0119]

[0120] Wherein: A1 is the average peak area of ​​the control solution; A2 is the peak area of ​​the sample solution; W1 is the average sample weight of the control solution, in g; W2 is the sample weight of the sample solution, in g; P is the average content of hexadecyl chloroformate in the control solution, in %.

[0121] The determination was repeated 4 times, and the average content of hexadecyl chloroformate measured is shown in Table 4.

[0122] Example 5

[0123] The difference from Example 1 is that the mass concentration of the sample solution is different:

[0124]

Chromatographic conditions

[0125] Chromatographic column: 250mm×4.6mm, C18 stainless steel column;

[0126] Mobile phase: 100% methanol;

[0127] Mobile phase flow rate: 1.0 mL / min;

[0128] Column temperature: 30°C;

[0129] Detection wavelength: 204nm;

[0130] Injection volume: 5 μL;

[0131] Analysis time: 12 minutes.

[0132]

Measurement steps

[0133] Step S1, weigh 0.50g (accurate to 0.0001g), 1.00g (accurate to 0.0001g), 2.00g (accurate to 0.0001g), 3.00g (accurate to 0.0001g), 4.00g (accurate to 0.0001g), 4.50g (accurate to 0.0001g) of hexadecyl chloroformate standard into 6 25ml volumetric flasks, dissolve and dilute to the mark with 1.2-dichloroethane, shake well for standby use, and obtain a series of control solutions. The series of control solutions are respectively measured by reversed-phase high performance liquid chromatography, and the linear results and linear relationship curves are the same as those in Example 1;

[0134] Step S2, weigh 1.25g (accurate to 0.0002g) of hexadecyl chloroformate sample to be tested (batch 1#) into a 25ml volumetric flask, dilute to the mark with 1.2-dichloroethane, shake well for standby use, and obtain a sample solution with a mass concentration of 0.05g / mL; the sample solution is subjected to content determination using reversed-phase high performance liquid chromatography to obtain a sample chromatographic response value, which is substituted into the linear relationship curve, and the content X1 of hexadecyl chloroformate in the sample to be tested is calculated by formula (1):

[0135]

[0136] Wherein: A1 is the average peak area of ​​the control solution; A2 is the peak area of ​​the sample solution; W1 is the average sample weight of the control solution, in g; W2 is the sample weight of the sample solution, in g; P is the average content of hexadecyl chloroformate in the control solution, in %.

[0137] The determination was repeated 4 times, and the average content of hexadecyl chloroformate measured is shown in Table 4.

[0138] Comparative Example 1

[0139] The difference from Example 1 is that the mobile phase is different:

[0140] Acetonitrile:acetic acid (volume ratio 100:0.1) was used as the mobile phase.

[0141] A typical reverse phase HPLC chromatogram of a sample solution is shown in Figure 3 .

[0142] Comparative Example 2

[0143] The difference from Example 1 is that the sample preparation solvent is different:

[0144] Ethanol was used as the sample preparation solvent.

[0145] The average content determination results of hexadecyl chloroformate in the above examples and comparative examples are shown in Table 4.

[0146] Table 4

[0147]

[0148]

[0149] As can be seen from the above, compared with the comparative example, the present invention uses methanol as the mobile phase, 1,2-dichloroethane as the solvent, and uses reversed-phase high performance liquid chromatography to accurately determine the content of hexadecyl chloroformate. The linear relationship curve provides a reliable basis for content calculation, making the measurement result more accurate and reliable; the specific chromatographic conditions are used to achieve stable and accurate detection of hexadecyl chloroformate, and the precision and relative range are not more than 0.7%, and the average recovery rate can reach 98%, which meets the needs of quality control and scientific research in industrial production. In addition, the present invention simplifies the preparation steps of the control solution and the sample solution, improves the operability and efficiency of the experiment, and can effectively improve the accuracy and speed of the determination of the content of hexadecyl chloroformate. The determination method of the present invention is simple to operate, highly sensitive, accurate and reliable, and low in cost. It can meet the actual measurement needs and make up for the blank of the related issues of the determination of the content of hexadecyl chloroformate in the prior art and literature.

[0150] In addition, it can be seen that when each process parameter is within the preferred range of the present invention, the overall effect is better.

[0151] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for determining the content of hexadecyl chloroformate, characterized in that: The following steps are involved: Step S1, dissolving a hexadecyl chloroformate standard with 1.2-dichloroethane to obtain a series of control solutions; using reversed-phase high performance liquid chromatography to determine the content of the series of control solutions, respectively, and establishing a linear relationship curve with the mass concentration of the hexadecyl chloroformate in the series of control solutions as the abscissa and the chromatographic response value of the series of control solutions as the ordinate; Step S2, dissolving the sample to be tested with 1.2-dichloroethane to obtain a sample solution; performing content determination on the sample solution using the reversed-phase high performance liquid chromatography to obtain a chromatographic response value of the sample solution, substituting the value into the linear relationship curve to obtain the content of hexadecyl chloroformate in the sample to be tested; Wherein, the mobile phase of the reversed-phase high performance liquid chromatography is methanol.

2. The measuring method according to claim 1, characterized in that The filler of the chromatographic column of the reversed-phase high performance liquid chromatography is C18 or C8.

3. The measuring method according to claim 1 or 2, characterized in that The size of the chromatographic column of the reversed-phase high performance liquid chromatography is 250 mm×4.6 mm or 150 mm×4.6 mm.

4. The measuring method according to any one of claims 1 to 3, characterized in that The flow rate of the mobile phase is 0.8-1.2 mL / min.

5. The measuring method according to any one of claims 1 to 4, characterized in that The detection wavelength of the reversed-phase high performance liquid chromatography is 195-230 nm.

6. The measuring method according to any one of claims 1 to 5, characterized in that The injection volume of the reversed-phase high performance liquid chromatography is 3 to 10 μL.

7. The measuring method according to any one of claims 1 to 6, characterized in that The column temperature of the reverse phase high performance liquid chromatography is 25-35°C.

8. The measuring method according to any one of claims 1 to 7, characterized in that The series of control solutions include at least 6 control solutions of different concentrations, wherein the mass concentrations of hexadecyl chloroformate are 0.0200 g / mL, 0.0410 g / mL, 0.0802 g / mL, 0.1160 g / mL, 0.1522 g / mL, and 0.1803 g / mL, respectively.

9. The measuring method according to any one of claims 1 to 8, characterized in that The mass concentration of the sample solution is 0.03-0.05 g / mL.

10. The measuring method according to any one of claims 1 to 9, characterized in that In step S2, the content X1 of hexadecyl chloroformate in the sample to be tested is calculated by formula (1): Wherein: A1 is the average peak area of ​​the control solution; A2 is the peak area of ​​the sample solution; W1 is the average sample weight of the control solution, in g; W2 is the weight of the sample solution, in g; P is the average content of hexadecyl chloroformate in the control solution, in %.

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