Method for detecting triethylamine in cefazolin sodium and application

Abstract

The invention discloses a method for detecting triethylamine in cefazolin sodium, which comprises the following steps: carrying out gas chromatography detection in a headspace sampling manner, recording a chromatogram, and carrying out quantitative analysis on the chromatogram by adopting an external standard method. Wherein the chromatographic column is a capillary chromatographic column with methylpolysiloxane as a stationary phase or a gas-phase capillary chromatographic column with equivalent efficiency; the temperature of a sample inlet is 200 DEG C; the temperature of a detector is 250 DEG C; in the temperature rising procedure, the change range of the initial temperature ranges from 35 DEG C to 45 DEG C, the temperature is maintained for 10 minutes, and the temperature is increased to 200 DEG C at the speed of 20 DEG C per minute and maintained for 2 minutes. The detection method provided by the invention has good specificity and system adaptability, good sample injection precision, extremely low detection limit and quantitation limit, good durability, good linearity, good accuracy and very high sensitivity, and can be widely applied to quality control of the cefazolin sodium product.

Description

Technical Field

[0001] The invention belongs to the technical field of drug analysis, and particularly relates to a detection method and application of triethylamine in cefazolin sodium. Background Art

[0002] The chemical name of cefazolin sodium is (6R,7R)-3-[[(5-methyl-1,3,4-thiadiazol-2-yl)thio]methyl]-7-[(1H-tetrazol-1-yl)acetylamino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid sodium salt. It is a first-generation cephalosporin with a broad antibacterial spectrum and is used to treat a variety of bacterial infections. The clinical indications for listing are: 1. It is suitable for the treatment of respiratory tract infections such as otitis media, bronchitis, pneumonia, urinary tract infections, skin and soft tissue infections, bone and joint infections, sepsis, infective endocarditis, hepatobiliary system infections, and eye, ear, nose, and throat infections caused by sensitive bacteria. 2. This product can also be used as a preventive drug before surgery. 3. This product should not be used for central nervous system infections. The efficacy is poor for chronic urinary tract infections, especially those with urinary tract anatomical abnormalities. This product should not be used to treat gonorrhea and syphilis.

[0003] Organic solvents such as triethylamine, acetone, methanol, dichloromethane, acetonitrile, N,N-dimethylformamide, N,N-dimethylaniline, etc. are used in the production of cefazolin sodium raw materials. Since residual solvents are impurities in drugs that are harmful to the human body, their content should be controlled within a limit during the production process.

[0004] At present, the United States Pharmacopoeia and the Chinese Pharmacopoeia (2020 edition) only include the quality standards of cefazolin sodium, but neither includes the detection method and standard for the residual solvent triethylamine in cefazolin sodium. In order to more comprehensively detect the content of residual solvent triethylamine in cefazolin sodium, it is necessary to establish a detection method for triethylamine in cefazolin sodium. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the defect of the detection method of the triethylamine residual solvent contained in cefazolin sodium in the prior art, and to provide a detection method and application of triethylamine in cefazolin sodium. The detection method of the present invention can realize the detection of triethylamine in cefazolin sodium. The methodological verification shows that the detection method of the present invention has good specificity and system adaptability, good injection precision, extremely low detection limit and quantitative limit, good durability, good linearity and good accuracy, and the method has high sensitivity, and can be widely used in the quality control of cefazolin sodium products.

[0006] The present invention provides a method for detecting triethylamine in cefazolin sodium, which is characterized in that it adopts gas chromatography detection in a headspace injection mode, records the chromatogram, and adopts an external standard method to perform quantitative analysis on the spectrum;

[0007] Among them, the detection conditions of the chromatography are:

[0008] Instrument: Gas chromatograph;

[0009] Chromatographic column: a capillary chromatographic column with methyl polysiloxane as the stationary phase or a gas phase capillary chromatographic column with equivalent performance;

[0010] Detector: hydrogen flame ionization detector (FID); carrier gas: nitrogen;

[0011] Inlet temperature: 200°C; Detector temperature: 250°C;

[0012] Heating program: the starting temperature ranges from 35°C to 45°C, maintained for 10 minutes, then raised to 200°C at a rate of 20°C per minute, maintained for 2 minutes;

[0013] Injection volume: 1 μl;

[0014] The detection process is:

[0015] (1) Solution preparation: (a) Solvent: dimethyl sulfoxide; (b) Test solution: take about 1.0 g of the product, weigh it accurately, put it into a 10 ml volumetric flask, add solvent to dissolve and dilute to the mark, shake well, and use it as the test solution; (c) Reference solution: accurately weigh an appropriate amount of triethylamine, add solvent to dissolve and dilute to make a solution containing about 500 μg of triethylamine per 1 ml, and use it as the reference solution;

[0016] (2) Determination method: Take 1 μl of the solvent and reference solution, inject them into the gas chromatograph, and record the chromatogram; calculate the content of the residual triethylamine solvent by the peak area according to the external standard method.

[0017] In a certain embodiment of the present invention, the triethylamine content calculated by the peak area according to the external standard method should not exceed 0.5%.

[0018] In a certain embodiment of the present invention, the external standard method calculation formula is:

[0019]

[0020] Where: As is the peak area of ​​triethylamine in the test solution;

[0021] Wr is the weight of the reference substance, mg;

[0022] Ar is the peak area of ​​triethylamine in the reference solution;

[0023] Ws is the weight of the test sample, mg;

[0024] Sr is the dilution multiple of the reference solution;

[0025] Ss is the dilution factor of the test solution.

[0026] In a certain embodiment of the present invention, the chromatographic column is a gas phase capillary chromatographic column with (5% phenyl)methyl polysiloxane as the stationary phase, or a capillary chromatographic column with equivalent performance. The specification of the chromatographic column is preferably DB-5MS, 30m×0.25mm×0.25μm, or a capillary chromatographic column with equivalent performance.

[0027] In a certain embodiment of the present invention, the column flow rate varies in the range of 0.8 ml / min to 1.2 ml / min, preferably 1.0 ml / min.

[0028] In a certain embodiment of the present invention, the split ratio is 5:1.

[0029] In a certain embodiment of the present invention, the temperature of the starting column varies in the range of 35°C to 45°C, preferably 40°C.

[0030] In a certain embodiment of the present invention, the detector is a hydrogen flame ionization detector.

[0031] The detection method of the present invention, the results of the method verification show that:

[0032] (1) The blank solvent did not interfere with the determination of triethylamine; the other solvents did not interfere with the determination of triethylamine, indicating that this method has good specificity.

[0033] (2) Durability: When the column flow rate was changed to 0.8 ml / min and 1.2 ml / min and the initial column temperature was 35°C and 45°C, the blank solvent and other solvents did not interfere with the determination of triethylamine. No triethylamine was detected in the test solution. The results showed that the method had good durability when the column flow rate was between 0.8 ml / min and 1.2 ml / min and the initial column temperature was between 35°C and 45°C.

[0034] (3) Linearity and range: triethylamine: y = 1,792,241x-1,612,428, r = 0.9997, concentration range: 51.260μg / ml ~ 768.900μg / ml, limit range: 10% ~ 150%, ratio: 0.17. Conclusion: The correlation coefficient of triethylamine is greater than 0.990, and the ratio is less than 25%. Triethylamine has a good linear relationship within the range of 10% to 150% of the concentration limit of the test solution.

[0035] (4) Limit of quantification and detection limit: The detection limit of triethylamine is 2.563 ng, which is equivalent to 0.0026% of the test sample concentration, and the detection limit of triethylamine is less than 1 / 5 of the limit concentration; the limit of quantification of triethylamine is 5.126 ng, which is equivalent to 0.0051% of the test sample concentration, and the limit of quantification of triethylamine is less than 1 / 2 of the limit concentration. Conclusion: This method has high sensitivity.

[0036] (5) Accuracy: The recovery rate is in the range of 80% to 120%; calculated by external standard method: the recovery rate is in the range of 94.72% to 100.33%; RSD is 2.20%, less than 10.0%. (n=9) Conclusion: This method has good accuracy.

[0037] (6) Precision: 1) Injection precision: The RSD of the peak area is 1.26%, which is less than 10.0%, and the instrument precision is good; 2) Repeatability: The RSD of the detection amount of triethylamine should not be greater than 10.0% (n=6) or the range of the detection amount of triethylamine in the test solution should not be greater than 0.02%; Result: No triethylamine was detected; 3) Intermediate precision: The RSD of the detection amount of triethylamine should not be greater than 10.0% (n=12) or the range of the detection amount of triethylamine in the test solution should not be greater than 0.02%; Result: No triethylamine was detected.

[0038] The present invention also provides an application of the above-mentioned method for detecting triethylamine in cefazolin sodium in detecting the content of triethylamine in a cefazolin sodium raw material or preparation.

[0039] In the present invention, the term "external standard method" refers to a method of using a pure product of the component to be measured as a reference substance and comparing the response signals of the reference substance and the component to be measured in the sample for quantitative analysis.

[0040] Without violating the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present invention.

[0041] The reagents and raw materials used in the present invention are commercially available.

[0042] The positive and progressive effects of the present invention are:

[0043] (1) The present invention can simply, quickly and accurately detect the residual amount of triethylamine in cefazolin sodium.

[0044] (2) The present invention has good specificity, and the blank solvent does not interfere with the determination of triethylamine; and the other solvents do not interfere with the determination of triethylamine.

[0045] (3) The method of the present invention is highly sensitive and has extremely low detection limits and quantification limits. The detection limit of triethylamine is 2.563 ng, which is equivalent to 0.0026% of the test sample concentration and can be effectively detected; the quantification limit of triethylamine is 5.126 ng, which is equivalent to 0.0051% of the test sample concentration and can be effectively quantified.

[0046] (4) The method described in the present invention has good linearity, good precision and durability.

[0047] (5) The method described in the present invention has good accuracy, and the recovery rate is in the range of 80% to 120%. Calculated by the external standard method: the recovery rate is in the range of 94.72% to 100.33%; the RSD is 2.20%. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 This is the GC spectrum of the triethylamine positioning solution in the exploration of chromatographic conditions for the solvent residue of triethylamine in Example 1.

[0049] Figure 2 This is the GC spectrum of the blank solvent used to explore the chromatographic conditions for the solvent residue of triethylamine in Example 2.

[0050] Figure 3 This is the GC spectrum of the reference solution for exploring the chromatographic conditions for the solvent residue of triethylamine in Example 2.

[0051] Figure 4 This is the GC spectrum of the triethylamine-specific solution in the method verification-specificity of the triethylamine solvent in Example 4.

[0052] Figure 5 This is the GC spectrum of the mixed solution in the method verification-specificity of the triethylamine solvent in Example 4.

[0053] Figure 6 GC chromatogram of the 100% linear solution (Linearity No. 3) in the method verification of triethylamine solvent in Example 6 - Linearity and range.

[0054] Figure 7 It is the linear correlation diagram of triethylamine in Example 6.

[0055] Figure 8 This is the GC spectrum of the quantitative limit solution in the method verification of triethylamine solvent in Example 7.

[0056] Fig. 9 This is the GC spectrum of the detection limit solution in the method verification of triethylamine solvent in Example 7.

[0057] Fig.10This is the GC spectrum of the 120% high concentration solution in the method verification-accuracy of the triethylamine solvent in Example 9.

[0058] Fig.11 This is the GC spectrum of the test solution in the method verification-intermediate precision of triethylamine solvent in Example 10. DETAILED DESCRIPTION

[0059] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the examples. The experimental methods in the following examples without specifying specific conditions are carried out according to conventional methods and conditions, or selected according to the product specifications.

[0060] Sample: Cefazolin sodium raw material (manufacturer: North China Pharmaceutical; batch number: K2501905022). Triethylamine (grade: HPLC, source manufacturer: MREDA), dimethyl sulfoxide (grade: HPLC, source manufacturer: MREDA). The remaining reagents in the present invention are of analytical grade.

[0061] Instruments: gas chromatograph (model Trace1300, manufacturer: Thermo), electronic balance (model ME204T and model XS105DU, both manufactured by: Mettler-Toledo Instrument Co., Ltd.), electronic balance (model CP214, manufacturer: OHVAS).

[0062] Example 1 Detection method development

[0063] Chromatographic conditions:

[0064] Chromatographic column: a capillary column with polyethylene glycol (or similar polarity) as the stationary phase (DB-WAX, 30m×0.32mm×1.0μm, or a chromatographic column with similar polarity);

[0065] Detector: FID; Carrier gas: nitrogen;

[0066] Inlet temperature: 200°C; Detector temperature: 250°C;

[0067] Heating program: starting temperature at 35°C, maintained for 5 minutes, then increased to 200°C at a rate of 10°C per minute, maintained for 2 minutes;

[0068] Flow rate: 2ml / min; split flow rate: 10ml / min;

[0069] Injection volume: 1μl; Hydrogen: 40ml / min;

[0070] Air: 40ml / min; Nitrogen: 40ml / min;

[0071] Solution preparation:

[0072] Solvent: dimethyl sulfoxide.

[0073] Reference substance positioning solution: accurately weigh approximately 3000 mg of methanol, 5000 mg of triethylamine, 410 mg of acetonitrile, 5000 mg of acetone, 600 mg of dichloromethane, and 880 mg of N,N-dimethylformamide, respectively, place in different 100 ml volumetric flasks, dilute to the scale with solvent, shake well, and prepare the reference substance positioning solution.

[0074] Reference solution: Take 1 ml of each reference solution and place it in a 100 ml volumetric flask, add solvent to dilute to the scale, shake well, and obtain the reference solution.

[0075] Take 1 μl of each of the above samples, inject into the gas chromatograph, and record the chromatogram. The results are shown in Table 1 and the spectrum is shown in Appendix. Figure 1 .

[0076] Table 1 Residual solvent method validation - mixed solution test results

[0077]

[0078] The results show that this method has good separation of each solvent (except triethylamine), appropriate peak time, good peak shape, and serious tailing of triethylamine, so it is considered to replace the chromatographic column for research.

[0079] Example 2 Detection Method Development

[0080] Chromatographic conditions:

[0081] Chromatographic column: a capillary column with (5% phenyl)methylpolysiloxane as the stationary phase (DB-5MS 30m×0.25mm×0.25μm, or a capillary column with equivalent performance);

[0082] Detector: FID; Carrier gas: nitrogen;

[0083] Inlet temperature: 200°C; Detector temperature: 250°C;

[0084] Heating program: starting temperature at 40°C, maintained for 1 minute, then heated to 200°C at a rate of 20°C per minute, maintained for 2 minutes;

[0085] Column flow rate: 2ml / min; split ratio: 5:1;

[0086] Injection volume: 1μl; Hydrogen: 40ml / min;

[0087] Air: 40ml / min; Nitrogen: 40ml / min;

[0088] Solution preparation:

[0089] Solvent: dimethyl sulfoxide

[0090] Reference substance stock solution: Accurately weigh about 5000 mg of triethylamine, place in a 100 ml volumetric flask, add solvent to dilute to the scale, shake well, and use as the reference substance stock solution.

[0091] Reference substance solution: Take 1 ml of reference substance stock solution and place it in a 100 ml volumetric flask. Add solvent to dilute to the scale and shake well to obtain reference substance solution.

[0092] Take 1 μl of solvent and reference solution respectively, inject into gas chromatograph and record the chromatogram. See attached for the chromatogram. Figure 2 ~Attached Figure 3 .

[0093] Results: The retention time of triethylamine was 2.344min, the tailing factor was 1.57, and the number of theoretical plates was 22160. The results showed that the peak shape of triethylamine was good in this method. Considering that the peak time of triethylamine was early, the initial temperature maintenance time in the method was extended from 1 minute to 10 minutes, and the column flow rate was adjusted to 1ml / min for subsequent verification.

[0094] Example 3 Detection method development

[0095] Chromatographic conditions:

[0096] Chromatographic column: a capillary column with (5% phenyl)methylpolysiloxane as the stationary phase (DB-5MS 30m×0.25mm×0.25μm, or a capillary column with equivalent performance);

[0097] Detector: FID; Carrier gas: nitrogen;

[0098] Inlet temperature: 200°C; Detector temperature: 250°C;

[0099] Heating program: starting temperature at 40°C, maintained for 10 minutes, then heated to 200°C at a rate of 20°C per minute, maintained for 2 minutes;

[0100] Column flow rate: 1ml / min; split ratio: 5:1;

[0101] Injection volume: 1 μl;

[0102] Solution preparation:

[0103] Solvent: dimethyl sulfoxide

[0104] Test solution: Take about 1.0g of the product, weigh accurately, place in a 10ml volumetric flask, add solvent to dissolve and dilute to the scale, shake well, and use as the test solution.

[0105] Reference solution: Accurately weigh an appropriate amount of triethylamine, dissolve it in a solvent and dilute it to make a solution containing about 500 μg of triethylamine per 1 ml as the reference solution.

[0106] Determination method: Take 1 μl of the reference solution, inject it into the gas chromatograph, and record the chromatogram.

[0107] Conclusion: The results show that triethylamine was not detected in this product, and the RSD of the peak area was 1.26%, which met the requirements and the results were good. This method will be used for subsequent verification.

[0108] Example 4 Method Validation - Specificity

[0109] Solvent: dimethyl sulfoxide.

[0110] Reference substance stock solution: Weigh approximately 300 mg of methanol, 500 mg of triethylamine, 41 mg of acetonitrile, 500 mg of acetone, 60 mg of dichloromethane, and 88 mg of N,N-dimethylformamide respectively, accurately weigh them, place them in different 100 ml volumetric flasks, add solvent to dilute to the scale, shake well, and use them as reference substance stock solution.

[0111] Mixed solution: Accurately measure 5 ml of each reference substance stock solution, place it in the same 50 ml volumetric flask, add solvent to dilute to the scale, shake well, and use as the mixed solution.

[0112] Reference substance solution: Accurately measure 5 ml of reference substance stock solution (triethylamine), place in a 50 ml volumetric flask, add solvent to dilute to the scale, shake well, and use as the reference substance solution.

[0113] Positioning solution: Take the stock solution of each reference substance as the positioning solution.

[0114] Test solution: Take about 1.0g of the product, weigh accurately, place in a 10ml volumetric flask, add solvent to dissolve and dilute to the scale, shake well, and use as the test solution.

[0115] Take 1 μl of each of the blank solvent, each positioning solution, reference solution, mixed solution, and test solution, inject them into the gas chromatograph, record the chromatogram, and examine the separation between the residual solvents. The results are shown in Table 1, and the spectrum of triethylamine is shown in the attached Figure 4 -Attached Figure 5 .

[0116] Table 2 Triethylamine method verification - mixed solution test results

[0117]

[0118]

[0119] Conclusion: Blank solvent and other solvents did not interfere with the determination of triethylamine. The results showed that this method had good specificity.

[0120] Example 5 Method Validation - Durability

[0121] In order to investigate the stability of the measurement results when the measurement conditions fluctuate slightly, the influence of changing the following conditions on the measurement results while keeping other conditions unchanged was investigated.

[0122] (1) Change the column flow rate by ±0.2 ml / min (1: 0.8 ml / min; 2: 1.2 ml / min).

[0123] (2) Change the starting column temperature by ±5°C (1: 35°C; 2: 45°C).

[0124] Solvent: dimethyl sulfoxide.

[0125] Reference substance stock solution: Weigh approximately 300 mg of methanol, 500 mg of triethylamine, 41 mg of acetonitrile, 500 mg of acetone, 60 mg of dichloromethane, and 88 mg of N,N-dimethylformamide, accurately weigh them, place them in different 100 ml volumetric flasks, add solvent to dilute to the scale, shake well, and use them as reference substance stock solution.

[0126] Mixed solution: Accurately measure 5 ml of each reference substance stock solution, place it in the same 50 ml volumetric flask, add solvent to dilute to the scale, shake well, and use as the mixed solution.

[0127] Test solution: Take about 1.0g of the product, weigh accurately, place in a 10ml volumetric flask, add solvent to dissolve and dilute to the scale, shake well, and use as the test solution.

[0128] Accurately measure 1 μl of blank solvent, mixed solution and test solution, inject them into gas chromatograph, and record the chromatogram.

[0129] The flow rate and starting column temperature were changed in the chromatographic conditions. The separation degree of each residual solvent peak and triethylamine peak in the mixed solution was used as the index, and the change of triethylamine detection amount (external standard method) in the test solution was used as the index to investigate the durability of the method. The results are shown in Table 3.

[0130] Table 3 Triethylamine method validation-durability test results

[0131]

[0132] Note: “*” represents normal conditions

[0133] Conclusion: When the column flow rate was changed to 0.8ml / min and 1.2ml / min and the initial column temperature was 35℃ and 45℃, the blank solvent and other solvents did not interfere with the determination of triethylamine; the separation degrees of triethylamine and its adjacent peaks in the mixed solution were greater than 1.5; no triethylamine was detected in the test solution. The results showed that the column flow rate was between 0.8ml / min and 1.2ml / min; the initial column temperature was between 35℃ and 45℃, and the method had good durability.

[0134] Example 6 Method Validation - Linearity and Range

[0135] Solvent: dimethyl sulfoxide.

[0136] Linear stock solution: Take about 500 mg of triethylamine, weigh it accurately, put it in a 100 ml volumetric flask, add solvent to dilute to the scale, shake well, and use it as the linear stock solution.

[0137] Linear solution: Accurately measure 0.1ml, 0.5ml, 1ml, 1.2ml and 1.5ml of the linear stock solution and place them in different 10ml volumetric flasks respectively. Add solvent to dilute to the scale and shake well. These are used as linear solutions No. 1 to 5.

[0138] Precisely take 1 μl of blank solvent and linear solutions 1 to 5, inject into gas chromatograph, record chromatogram, and perform linear regression with concentration as horizontal axis and peak area as vertical axis. The results are shown in Table 4 and the spectrum is shown in Appendix Figure 6 .

[0139] Table 4 Triethylamine method validation - linearity test results

[0140]

[0141]

[0142] Note:

[0143]

[0144] Conclusion: The linear equation of triethylamine is y=1,792,241x-1,612,428, r=0.9997, concentration range: 51.260μg / ml~768.900μg / ml, limit range: 10%~150%, ratio: 0.17%.

[0145] The results showed that the correlation coefficient of triethylamine was greater than 0.990, the ratio was less than 25%, and the linear relationship of triethylamine was good within the range of 10% to 150% of the concentration limit of the test solution.

[0146] Example 6 Method Validation - Limit of Quantitation and Limit of Detection

[0147] Blank solvent: dimethyl sulfoxide.

[0148] Quantitative limit solution and detection line solution: According to the S / N value of linear solution No. 1 under "Linearity and Range", the quantitative limit concentration is inferred. The linear stock solution under "Linearity and Range" is diluted step by step to S / N of about 10 as the quantitative limit solution, and S / N of about 3 as the detection limit solution. The results are shown in Table 5 and Table 6 respectively, and the spectrum is shown in the attached Figure 8 ~Attached Fig. 9 .

[0149] Table 5 Triethylamine method validation - quantitation limit results

[0150]

[0151] Table 6 Triethylamine method validation - detection limit results

[0152]

[0153] Conclusion: The proposed inspection concentration of cefazolin sodium is 100mg / ml, and the detection limit of triethylamine is 2.563ng, which is equivalent to 0.0026% of the test sample concentration and can be effectively detected. The detection limit of triethylamine is less than 1 / 5 of the limit concentration; the quantification limit of triethylamine is 5.126ng, which is equivalent to 0.0051% of the test sample concentration and can be effectively quantified. The quantification limit of triethylamine is less than 1 / 2 of the limit concentration. The results show that this method has high sensitivity.

[0154] Example 8 Method Validation - Injection Precision and Repeatability

[0155] Solvent: dimethyl sulfoxide.

[0156] Reference solution: Take about 500 mg of triethylamine, accurately weigh it, place it in a 100 ml volumetric flask, add solvent to dilute to the scale, shake well, accurately measure 1 ml of the above solution, place it in a 10 ml volumetric flask, add solvent to dilute to the scale, shake well, and obtain.

[0157] Test solution: Take about 1.0g of the product, weigh accurately, put it in a 10ml volumetric flask, add solvent to dissolve and dilute to the scale, shake well, and prepare 6 portions in parallel.

[0158] Accurately measure 1 μl of blank solvent, reference solution and test solution, inject them into gas chromatograph, record the chromatogram, and calculate the content of triethylamine in the test solution by peak area according to the external standard method.

[0159] The reference solution was used as the injection precision solution and injected 6 times in succession. The results are shown in Tables 7 and 8 respectively.

[0160] Table 7 Triethylamine method validation - injection precision test results

[0161]

[0162] Conclusion: The RSD of the triethylamine peak area is 1.26%, which is less than 1.00%, indicating that the instrument has good precision.

[0163] Table 8 Triethylamine method validation - repeatability test results

[0164]

[0165] Conclusion: Triethylamine was not detected.

[0166] Example 9 Method Validation - Accuracy

[0167] Solvent: dimethyl sulfoxide.

[0168] Original quantity: Use the result data of “repeat experiment”.

[0169] Reference substance stock solution: Take about 500 mg of triethylamine, weigh accurately, place in a 100 ml volumetric flask, add solvent to dilute to the scale, shake well, and use as the reference substance stock solution.

[0170] Reference substance solution: Accurately measure 1 ml of reference substance stock solution, place in a 10 ml volumetric flask, add solvent to dilute to the scale, shake well, and obtain.

[0171] Low concentration test solution (80%): Take about 1.0g of this product, weigh accurately, put it in a 10ml volumetric flask, add 0.8ml of reference stock solution, an appropriate amount of solvent, shake to dissolve, and dilute to the scale, shake well, as 80% test solution. Prepare 3 copies in parallel.

[0172] Medium concentration test solution (100%): Take about 1.0g of this product, weigh accurately, put it in a 10ml volumetric flask, add 1.0ml of reference substance stock solution, an appropriate amount of solvent, shake to dissolve, and dilute to the scale, shake well, as the 100% test solution. Prepare 3 copies in parallel.

[0173] High concentration test solution (120%): Take about 1.0g of this product, weigh accurately, put it in a 10ml volumetric flask, add 1.2ml of reference stock solution, an appropriate amount of solvent, shake to dissolve, and dilute to the scale, shake well, as the 120% test solution. Prepare 3 copies in parallel.

[0174] Accurately measure 1 μl of blank solvent, reference solution and test solution, inject into gas chromatograph, record chromatogram, and calculate the content of triethylamine in the test solution by external standard method. The results are shown in Table 9 and the spectrum is shown in Attachment Fig.10 .

[0175] Table 9 Triethylamine method verification - accuracy test results

[0176]

[0177] Conclusion: According to the external standard method, the recovery rate of triethylamine is in the range of 94.72% to 100.33%; the RSD is 2.20% (n=9), which is less than 10.0%. This method has good accuracy.

[0178] Example 10 Method Verification - Intermediate Precision

[0179] Solvent: dimethyl sulfoxide.

[0180] Reference solution: Take about 500 mg of triethylamine, accurately weigh it, place it in a 100 ml volumetric flask, add solvent to dilute to the scale, shake well, accurately measure 1 ml of the above solution, place it in a 10 ml volumetric flask, add solvent to dilute to the scale, shake well, and obtain.

[0181] Test solution: Take about 1.0g of the product, weigh accurately, put it in a 10ml volumetric flask, add solvent to dissolve and dilute to the scale, shake well, and prepare 6 copies in parallel.

[0182] Different personnel, at different times, used different instruments to determine the repeatability of the test method. Accurately measure 1 μl of blank solvent, reference solution and test solution, inject into the gas chromatograph, record the chromatogram, and calculate the content of triethylamine in the test solution by peak area according to the external standard method. The results are shown in Table 10 and the spectrum is shown in the attached Fig.11 .

[0183] Table 10 Triethylamine method validation - intermediate precision test results

[0184]

[0185] Conclusion: Triethylamine was not detected, indicating that the intermediate precision was good.

Claims

1. A method for detecting triethylamine in cefazolin sodium, characterized in that, It adopts gas chromatography detection by headspace injection, records the chromatogram, and uses external standard method to conduct quantitative analysis on the spectrum; Among them, the detection conditions of the chromatography are: Instrument: Gas chromatograph; Chromatographic column: a capillary chromatographic column with methyl polysiloxane as the stationary phase or a gas phase capillary chromatographic column with equivalent performance; Detector: hydrogen flame ionization detector (FID); carrier gas: nitrogen; Inlet temperature: 200°C; Detector temperature: 250°C; Heating program: The initial column temperature range is between 35°C and 45°C, maintained for 10 minutes, and then increased to 200°C at a rate of 20°C per minute and maintained for 2 minutes; Injection volume: 1 μl; The detection process is: (1) Solution preparation: (a) Solvent: dimethyl sulfoxide; (b) Test solution: take about 1.0 g of the product, weigh it accurately, put it into a 10 ml volumetric flask, add solvent to dissolve and dilute to the mark, shake well, and use it as the test solution; (c) Reference solution: accurately weigh an appropriate amount of triethylamine, add solvent to dissolve and dilute to make a solution containing about 500 μg of triethylamine per 1 ml, and use it as the reference solution; (2) Determination method: Take 1 μl of the solvent and reference solution, inject them into the gas chromatograph, and record the chromatogram; calculate the content of the residual triethylamine solvent by the peak area according to the external standard method.

2. The method for detecting triethylamine in cefazolin sodium according to claim 1, wherein: The triethylamine content should not exceed 0.5% by calculating the peak area according to the external standard method.

3. The method for detecting triethylamine in cefazolin sodium according to claim 2, characterized in that: The external standard method calculation formula is: Where: As is the peak area of ​​triethylamine in the test solution; Wr is the weight of the reference substance, mg; Ar is the peak area of ​​triethylamine in the reference solution; Ws is the weight of the test sample, mg; Sr is the dilution multiple of the reference solution; Ss is the dilution factor of the test solution.

4. The method for detecting triethylamine in cefazolin sodium according to claim 1, wherein: The chromatographic column is a gas phase capillary chromatographic column with (5% phenyl)methyl polysiloxane as a stationary phase, or a capillary chromatographic column with equivalent performance.

5. The method for detecting triethylamine in cefazolin sodium according to claim 4, characterized in that: The specification of the chromatographic column is DB-5MS, 30m×0.25mm×0.25μm, or a capillary chromatographic column with equivalent performance.

6. The method for detecting triethylamine in cefazolin sodium according to claim 1, characterized in that: The column flow rate varies in the range of 0.8 ml / min to 1.2 ml / min.

7. The method for detecting triethylamine in cefazolin sodium according to claim 6, characterized in that: The column flow rate was 1.0 ml / min.

8. The method for detecting triethylamine in cefazolin sodium according to claim 1, characterized in that: The split ratio is 5:

1.

9. The method for detecting triethylamine in cefazolin sodium according to claim 1, characterized in that: The starting column temperature is preferably 40°C.

10. A method for detecting triethylamine in cefazolin sodium as claimed in any one of claims 1 to 9, and use thereof in detecting the content of triethylamine in a cefazolin sodium bulk drug or preparation.

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