Detection method of revienacin inhalation solution

Abstract

The invention relates to a detection method of a revivacin inhalation solution, and belongs to the technical field of medicine detection. According to the detection method provided by the invention, a revivin inhalation solution sample is analyzed by adopting high performance liquid chromatography to obtain the content of impurities in the revivin inhalation solution; the high performance liquid chromatography uses a phosphate buffer as a mobile phase A and acetonitrile as a mobile phase B, and the elution conditions are as follows: 0-5 min, the volume ratio of the mobile phase A to the mobile phase B is gradually changed from 95: 5 to 80: 20; the volume ratio of the mobile phase A to the mobile phase B is gradually changed from 80: 20 to 20: 80 in 5-30 min; the volume ratio of the mobile phase A to the mobile phase B is 95: 5. The method provided by the invention can realize accurate detection of five different impurities in the revienacin inhalation solution, and is beneficial to actual production quality control and improvement of drug safety.

Description

Technical Field

[0001] This invention relates to the field of drug detection technology, and in particular to a method for detecting Revinapine inhalation solution. Background Technology

[0002] Revinac, chemically named 1-[2-[4-[(4-carbamoyl-1-piperidinyl)methyl]-N-methylbenzoamide]ethyl]-4-piperidinyl 2-biphenylcarbamate, is a long-acting muscarinic antagonist (LAMA) and bronchodilator for chronic obstructive pulmonary disease (COPD). It is administered via nebulized inhalation solution to improve lung function, reduce clinical symptoms of COPD, and prevent further disease progression. It is used for maintenance therapy in COPD patients.

[0003] The impurities in Revinapine inhalation solution mainly include starting materials, intermediates, polymers, by-reaction products, and degradation products introduced during the production process and storage. Research on these impurities in Revinapine inhalation solution is a crucial aspect of drug quality research. Their content is not only a direct indicator of drug purity but also has significant safety implications; excessive levels may adversely affect drug purity and safety. Currently, this drug is not listed in the pharmacopoeias of various countries, including CHP, USP, JP, IP, EP, and BP, and methods for detecting degradation impurities and related substances are rarely reported.

[0004] Therefore, there is an urgent need to develop a method for detecting impurities in revinapine inhalation solution that is accurate, sensitive, has high separation, low detection cost, and good stability, in order to strengthen production quality control and improve drug safety. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a method for detecting revinapine inhalation solution. The method provided by this invention can simultaneously and accurately detect five different impurities in revinapine inhalation solution, thereby enhancing drug safety.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: This invention provides a method for detecting revinaporone inhalation solution, comprising the following steps: The content of impurities in the revinapine inhalation solution was determined by high performance liquid chromatography. The high-performance liquid chromatography method uses phosphate buffer as mobile phase A and acetonitrile as mobile phase B, with the following elution conditions: From 0 to 5 minutes, the volume ratio of mobile phase A to mobile phase B gradually changed from 95:5 to 80:20. Over 5-30 minutes, the volume ratio of mobile phase A to mobile phase B gradually changed from 80:20 to 20:80. The volume ratio of mobile phase A to mobile phase B is 95:5 for 36-45 min.

[0007] The functional ingredient in Revinalcin inhalation solution is Revinalcin (molecular formula: C). 35 H 43 The molecular structure of N5O4 (molecular weight: 597.76) is as follows: ; The detection method provided by this invention is for detecting the following five different impurities: Impurity A is 1-(2-(methylamino)ethyl)piperidin-4-yl[1,1'-biphenyl]-2-ylcarbamate, CAS: 743460-48-2, molecular formula C 21 H 27 N3O2, molecular weight (MW): 353.47, structure as follows: (Impurity A); Impurity B is 4-((4-carbamoylpiperidin-1-yl)methyl)benzoic acid, CAS: 938143-02-3, molecular formula C 14 H 18 N2O3, molecular weight (MW): 262.30, structure as follows: (Impurity B) Impurity C is 1-(4-((2-(4-([1,1'-biphenyl]-2-ylcarbamoyl)oxy)piperidin-1-yl)ethyl(methyl)carbamoyl)benzyl)piperidin-4-carboxylic acid, CAS: 909800-36-8, molecular formula C 35 H 42 N4O5, molecular weight (MW): 598.74, structure as follows: (Impurity C); Impurity D is 1-(2-(3-formyl-N-methylbenzoylamino)ethyl)piperidin-4-yl[1,1'-biphenyl]-2-ylcarbamate, CAS: 864760-28-1, molecular formula C 29 H 31 N3O4, molecular weight (MW): 485.58, structure as follows: (Impurity D); Impurity E is o-aminobiphenyl, CAS: 90-41-5, molecular formula C 12 H 11 N, molecular weight (MW): 169.23, structure as follows: (Impurity E); Among them, impurity A is a residual intermediate from the synthesis process, and excessive content may increase the risk of local respiratory irritation; impurity B is a degradation impurity or process impurity, and excessive content will reduce the actual content of the active ingredient in the drug, may slightly increase respiratory irritation, and affect the storage stability of the drug; impurity C is a by-product of the synthesis process, and excessive content poses a toxic risk and reduces the purity of the drug; impurity D is an oxidative degradation product of the new molecule of revinnain, and excessive content may cause respiratory allergic or irritant reactions and reduce the effective concentration of the drug; impurity E is an impurity introduced from the starting material or a degradation impurity, which is a genotoxic impurity and is also classified as a Group 2A carcinogen by the International Agency for Research on Cancer (IARC), and may also cause respiratory allergic reactions.

[0008] The detection method for Revinapine inhalation solution provided by this invention, through the design of specific high-performance liquid chromatography elution conditions, achieves excellent separation of five impurities, with separation accuracy meeting detection requirements, good specificity, and no interference. Simultaneously, each impurity exhibits good linear response, high accuracy, good precision, and reproducible results, making it suitable for rapid detection in the large-scale production and quality control of Revinapine inhalation solution. This invention provides a method capable of simultaneously separating and detecting five impurities of different sources and types in Revinapine, thereby achieving quality monitoring covering the entire production process of Revinapine inhalation solution and improving drug safety.

[0009] Preferably, the concentration of revinapine in the revinapine inhalation solution sample is 5-60 μg / mL.

[0010] When using the detection method of this application to detect Revinapine inhalation solution, the sample can be injected directly for detection, or it can be diluted with solvent before injection for detection; preferably, a blank excipient solution is used for dilution.

[0011] Preferably, the detection wavelength of the high-performance liquid chromatography is 190-260 nm.

[0012] More preferably, the detection wavelength of the high-performance liquid chromatography is 230 nm.

[0013] Preferably, the phosphate buffer includes at least one of sodium dihydrogen phosphate, disodium hydrogen phosphate, potassium dihydrogen phosphate, and dipotassium hydrogen phosphate.

[0014] Preferably, the concentration of phosphate in the phosphate buffer solution is 0.01-0.1 mol / L.

[0015] Preferably, the pH of the phosphate buffer solution is 2-5.

[0016] More preferably, the phosphate buffer comprises potassium dihydrogen phosphate, wherein the concentration of potassium dihydrogen phosphate is 0.02 mol / L, and the pH of the phosphate buffer is 3-4.

[0017] Preferably, the mobile phase flow rate of the high-performance liquid chromatography is 0.5-1.5 mL / min, and the injection volume is 5-50 μL.

[0018] More preferably, the mobile phase flow rate of the high-performance liquid chromatography is 1 mL / min, and the injection volume is 50 μL.

[0019] Preferably, the chromatographic column of the high performance liquid chromatography method comprises an octadecylsilane-bonded silica column, wherein the octadecylsilane-bonded silica column has the following specifications: column length 4.6 mm, inner diameter 250 mm, and particle size 5 μm.

[0020] Preferably, the column temperature of the high-performance liquid chromatography is 45-55℃.

[0021] More preferably, the column temperature of the high-performance liquid chromatography is 50°C.

[0022] Preferably, the high-performance liquid chromatography (HPLC) begins elution after treatment with a trapping column, wherein the trapping column is an octylsilane-bonded silica column.

[0023] Before elution, a trapping column is used to selectively trap ghost peak pollutants and adsorb and retain impurities that will produce ghost peaks.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention provides a method for detecting revinnain inhalation solution. By optimizing the elution conditions of high-performance liquid chromatography (HPLC), it achieves effective separation and accurate detection of five different impurities in revinnain inhalation solution. The method of this invention exhibits good peak shapes and excellent separation for the components in revinnain inhalation solution, and shows significant advantages in specificity, limit of quantitation, limit of detection, linearity, precision, and accuracy. By adopting the detection method of this invention, different impurities in revinnain inhalation solution can be comprehensively detected and controlled, production quality control can be strengthened, and drug safety can be improved. It also provides a new detection approach for the development of related substances detection in revinnain inhalation solution. Attached Figure Description

[0025] Figure 1 The chromatogram of the system suitability solution for the detection method of the new inhalation solution of Revinaprine of the present invention is shown. Figure 2 The chromatogram of the solvent (blank excipient solution) was determined using the detection method for Revinaprine inhalation solution of the present invention. Figure 3The chromatogram of the target solution for impurity A was obtained by using the detection method of the new inhalation solution of Revinaprine of the present invention. Figure 4 The chromatogram of the impurity B localization solution was obtained by using the detection method of the new inhalation solution of Revinaprine of the present invention. Figure 5 The chromatogram of the impurity C localization solution was obtained by using the detection method of the new inhalation solution of Revinaprine of the present invention. Figure 6 The chromatogram of the D-positioning solution was obtained by detecting impurity using the detection method of the new inhalation solution of Revinaprine of the present invention. Figure 7 The chromatogram of the impurity E localization solution was obtained by using the detection method of the new inhalation solution of Revinaprine of the present invention. Figure 8 This is a chromatogram overlay of the specificity test results for the detection method of the new inhaled solution of Revinaprine of the present invention. Detailed Implementation

[0026] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments. Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods; the materials and reagents used, unless otherwise specified, are commercially available reagents and materials.

[0027] The CAS numbers and procurement sources of the impurity reference standards used in the following experimental examples, embodiments, and comparative examples are shown in Table 1 below.

[0028] Table 1 The high-performance liquid chromatography (HPLC) methods used in Experiments 1-4 below are as follows: An octadecylsilane-bonded silica column (Welch Ultimate XB-C18, 4.6 mm × 250 mm, 5 μm) was used as the chromatographic column. The column temperature was set to 50 °C, the detection wavelength to 230 nm, and the injection volume to 50 μl. Mobile phase A was phosphate buffer (prepared by dissolving 2.72 g of potassium dihydrogen phosphate in water and diluting to 1000 mL, then adjusting the pH to 3.5 with phosphoric acid). Mobile phase B was acetonitrile. After online filtration using a Welch Ghost-Buster Column (4.6 mm × 50 mm), gradient elution was performed under the following conditions: the flow rate of the mobile phase was 1.0 mL / min. Initially, the volume ratio of mobile phase A to mobile phase B is 95:5; From 0 to 5 minutes, the volume ratio of mobile phase A to mobile phase B gradually changed from 95:5 to 80:20. Over 5-30 minutes, the volume ratio of mobile phase A to mobile phase B gradually changed from 80:20 to 20:80. The volume ratio of mobile phase A to mobile phase B is 95:5 for 36-45 min.

[0029] Experimental Example 1 To verify the specificity of the detection method for Revinaprine inhalation solution provided by this invention, the following sample solutions were tested: Solution preparation: Solvent (i.e. blank excipient solution): Take 9g of sodium chloride, 0.6g of citric acid and 2.0g of sodium citrate, dissolve them in water and dilute to 1000mL, mix well and adjust the pH to 5.0 with hydrochloric acid.

[0030] Impurity A reference standard stock solution: Accurately weigh 5 mg of impurity A reference standard, place it in a 100 mL volumetric flask, add an appropriate amount of solvent, shake to dissolve, and dilute to the mark with solvent.

[0031] Impurity B reference standard stock solution: Accurately weigh 5 mg of impurity B reference standard, place it in a 100 mL volumetric flask, add a small amount of methanol and shake to dissolve, and dilute to the mark with solvent.

[0032] Impurity C reference standard stock solution: Accurately weigh 5 mg of impurity C reference standard, place it in a 100 mL volumetric flask, add a small amount of methanol and shake to dissolve, and dilute to the mark with solvent.

[0033] Impurity D reference standard stock solution: Accurately weigh 5 mg of impurity D reference standard, place it in a 100 mL volumetric flask, add a small amount of methanol, shake to dissolve, and dilute to the mark with solvent.

[0034] Impurity E reference standard stock solution: Accurately weigh 5 mg of impurity E reference standard, place it in a 100 mL volumetric flask, add a small amount of methanol and shake to dissolve, and dilute to the mark with solvent.

[0035] Impurity A positioning solution: Accurately measure 1 mL of impurity A reference standard stock solution, place it in a 100 mL volumetric flask, dilute to the mark with solvent, and shake well.

[0036] Impurity B positioning solution: Accurately measure 1 mL of impurity B reference standard stock solution, place it in a 100 mL volumetric flask, dilute to the mark with solvent, and shake well.

[0037] Impurity C positioning solution: Accurately measure 1 mL of impurity C reference standard stock solution, place it in a 100 mL volumetric flask, dilute to the mark with solvent, and shake well.

[0038] Impurity D positioning solution: Accurately measure 1 mL of impurity D reference standard stock solution, place it in a 100 mL volumetric flask, dilute to the mark with solvent, and shake well.

[0039] Impurity E positioning solution: Accurately measure 1 mL of impurity E reference standard stock solution, place it in a 100 mL volumetric flask, dilute to the mark with solvent, and shake well.

[0040] System suitability solution: Accurately weigh 6 mg of Revinapine reference standard and place it in a 100 mL volumetric flask. Add an appropriate amount of solvent and shake to dissolve. Then, accurately measure 1 mL each of the stock solutions of impurity A, impurity B, impurity C, impurity D, and impurity E. Dilute with solvent to prepare a mixed solution containing approximately 60 µg of Revinapine per 1 mL, with each of the following impurities: impurity A 0.5 µg, impurity B 0.5 µg, impurity C 0.5 µg, impurity D 0.5 µg, and impurity E 0.5 µg.

[0041] The solvent (blank excipient solution), system suitability solution, and localization solutions of each impurity obtained from the above preparation were analyzed by high-performance liquid chromatography (HPLC). The results are as follows: Figure 1-8 and Table 2, in which Figure 1 High-performance liquid chromatography (HPLC) chromatogram of the obtained system suitability solution; Figure 2 The high-performance liquid chromatogram of the solvent (blank excipient solution) obtained by detection; Figure 3-7 The figures show the high-performance liquid chromatograms of the solutions containing the detected impurities A, B, C, D, and E. Figure 8 This is a superimposed comparison graph of the above chromatographic results.

[0042] Table 2 From Table 2 and Figure 1-8 It can be known that: Comparing the high-performance liquid chromatography (HPLC) chromatograms of the five impurity localization solutions with those of the system suitability solution, based on the retention time (RT) and relative retention time (RRT), it can be seen that the detection method provided by this invention can accurately separate and detect revinapine and impurities A to E in the revinapine inhalation solution, with good peak shapes and resolutions significantly higher than 1.5. Furthermore, no interference was observed at the corresponding retention times in the HPLC chromatogram of the solvent (blank excipient solution) detected by this method, indicating that the detection method for revinapine inhalation solution provided by this invention has good specificity.

[0043] Experiment Example 2 To verify the linearity and range of the detection method for Revinaprine inhalation solution provided by this invention, the following sample solutions were tested: The solvent (blank excipient solution) is the same as in Experiment 1.

[0044] Linear stock solution of impurity A: Accurately weigh 10 mg of impurity A reference standard, place it in a 100 ml volumetric flask, add an appropriate amount of solvent and shake to dissolve, then dilute to the mark with solvent.

[0045] Linear stock solution of impurity B: Accurately weigh 10 mg of impurity B reference standard, place it in a 100 ml volumetric flask, add a small amount of methanol and shake to dissolve, then dilute to the mark with solvent.

[0046] Linear stock solution of impurity C: Accurately weigh 10 mg of impurity C reference standard, place it in a 100 ml volumetric flask, add a small amount of methanol and shake to dissolve, then dilute to the mark with solvent.

[0047] Linear stock solution of impurity D: Accurately weigh 10 mg of impurity D reference standard, place it in a 100 ml volumetric flask, add a small amount of methanol and shake to dissolve, then dilute to the mark with solvent.

[0048] Linear stock solution of impurity E: Accurately weigh 10 mg of impurity E reference standard, place it in a 100 ml volumetric flask, add a small amount of methanol and shake to dissolve, then dilute to the mark with solvent.

[0049] Linear solutions: Accurately measure appropriate amounts of the linear stock solution and quantitatively dilute it with solvent to prepare a series of linear solutions and limit-of-quantity solutions with concentrations of 25%, 50%, 100%, 150%, and 200% of the limit concentrations of each component.

[0050] The linear solution obtained by the above preparation was analyzed by high performance liquid chromatography. Linear regression was performed with concentration (µg / ml) on the x-axis and peak area on the y-axis. The results were as follows: For impurity A in the concentration range of 0.020 μg / mL to 0.990 μg / mL (limit of quantitation concentration to 200% limit concentration), the linear equation is y = 162.75x + 0.2972, and the linear correlation coefficient r is 1.0000. For impurity B in the concentration range of 0.020~0.982 μg / mL (limit of quantitation concentration to 200% limit concentration), the linear equation is y=136.74x-0.3592, and the linear correlation coefficient r is 0.9999. For impurity C in the concentration range of 0.020~0.980 μg / mL (limit of quantitation concentration to 200% limit concentration), the linear equation is y=119.31x-0.0942, and the linear correlation coefficient r is 1.0000; For impurity D in the concentration range of 0.005~1.000 μg / mL (limit of quantitation concentration to 200% limit concentration), the linear equation is y=135.88x+0.6775, and the linear correlation coefficient r is 0.9987. For impurity E in the concentration range of 0.005~1.013 μg / mL (limit of quantitation concentration to 200% limit concentration), the linear equation is y=292.45x-0.003, and the linear correlation coefficient r is 1.0000.

[0051] The above results indicate that the detection method for Revinaprine inhalation solution provided by this invention has good linear response to impurities A to E of different concentrations and can be used for quantitative analysis.

[0052] Experimental Example 3 To verify the detection accuracy of the detection method for Revinaprine inhalation solution provided by this invention, the following sample solutions were tested: Revinapine solution: Take revinapine reference standard and prepare a solution with a concentration of 60 μg / ml using a solvent (blank excipient solution, same as in Experiment 1); Spiked solutions of impurities A to E: The stock solutions of impurities A to E from Experimental Example 1 were spiked to prepare three different levels of spiked solutions equivalent to 50%, 100%, and 150% of the limit concentration. Recovery tests were conducted using the high-performance liquid chromatography (HPLC) method described in Experimental Example 2. The average recovery results for each concentration are shown in Table 3 below. Table 3 The recoveries of impurity A at all concentrations ranged from 98.31% to 103.33%, with an RSD of 1.7%; the recoveries of impurity B at all concentrations ranged from 94.33% to 101.36%, with an RSD of 2.1%; the recoveries of impurity C at all concentrations ranged from 102.36% to 104.96%, with an RSD of 0.8%; the recoveries of impurity D at all concentrations ranged from 101.79% to 103.45%, with an RSD of 0.5%; and the recoveries of impurity E at all concentrations ranged from 100.57% to 105.38%, with an RSD of 1.7%.

[0053] The above results show that the detection method for Revinapine inhalation solution provided by the present invention has good accuracy in detecting the five impurities.

[0054] Experiment Example 4 To verify the detection precision of the detection method for Revinaprine inhalation solution provided by this invention, the following sample solutions were tested: Take a sample of Revinapine inhalation solution directly, and prepare 6 spiked solutions of each substance at 100% concentration according to the method in Experimental Example 3. Calculate the content of each impurity by referring to the high performance liquid chromatography analysis method in Experimental Example 2.

[0055] In the repeatability test of six spiked samples for each component, the RSD of impurity A was 2.0%, the RSD of impurity B was 0.4%, the RSD of impurity C was 2.0%, the RSD of impurity D was 2.1%, the RSD of impurity E was 1.9%, the RSD of other unknown maximum single impurity content was 2.1%, and the RSD of total impurities was 1.6%. It can be seen that the detection method provided by the present invention has good repeatability and high precision.

[0056] Example 1 Revinaporne inhalation solution was directly used as a sample for high performance liquid chromatography analysis: an octadecylsilane bonded silica column (Welch Ultimate XB-C18, 4.6mm×250mm, 5μm) was used as the chromatographic column, the column temperature was set to 50℃, the detection wavelength was 230nm, and the injection volume was 50μl. Mobile phase A was phosphate buffer (prepared by dissolving 2.72 g of potassium dihydrogen phosphate in water and diluting to 1000 mL, then adjusting the pH to 3.5 with phosphoric acid). Mobile phase B was acetonitrile. After online filtration using a Welch Ghost-Buster Column (4.6 mm × 50 mm), gradient elution was performed under the following conditions: the flow rate of the mobile phase was 1.0 mL / min. Initially, the volume ratio of mobile phase A to mobile phase B is 95:5; From 0 to 5 minutes, the volume ratio of mobile phase A to mobile phase B gradually changed from 95:5 to 80:20. Over 5-30 minutes, the volume ratio of mobile phase A to mobile phase B gradually changed from 80:20 to 20:80. The volume ratio of mobile phase A to mobile phase B is 95:5 for 36-45 min.

[0057] The test results are as follows: Impurity A was not detected, impurity B was not detected, impurity C had a mass content of 0.11%, impurity D was not detected, impurity E was not detected, a single unknown impurity was not detected, and the total impurity content was 0.11%.

[0058] Comparative Example 1 The only difference between Comparative Example 1 and Example 1 is that the gradient elution conditions are adjusted as follows: Initially, the volume ratio of mobile phase A to mobile phase B is 85:15; From 0 to 5 minutes, the volume ratio of mobile phase A to mobile phase B gradually changed from 85:15 to 65:35. Over 5-30 minutes, the volume ratio of mobile phase A to mobile phase B gradually changed from 65:35 to 35:65. The volume ratio of mobile phase A to mobile phase B is 85:5 for 36-45 min.

[0059] Compared with the elution gradient used in this invention, Comparative Example 1 could not separate revinnacin from impurity C, and no impurity was detected.

[0060] In summary, this invention provides a method for detecting revinnacin inhalation solution. By optimizing the elution conditions of high-performance liquid chromatography, it achieves effective separation and accurate detection of revinnacin and five different impurities in the revinnacin inhalation solution. By adopting the detection method of this invention, different impurities in revinnacin inhalation solution can be comprehensively detected and controlled, production quality control can be strengthened, and drug safety can be improved. It also provides a new detection approach for developing related substances detection methods for revinnacin inhalation solution.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A method for detecting Revinaprine inhalation solution, characterized in that, Includes the following steps: The content of impurities in the revinapine inhalation solution was determined by high performance liquid chromatography. The high-performance liquid chromatography method uses phosphate buffer as mobile phase A and acetonitrile as mobile phase B, with the following elution conditions: From 0 to 5 minutes, the volume ratio of mobile phase A to mobile phase B gradually changed from 95:5 to 80:

20. Over 5-30 minutes, the volume ratio of mobile phase A to mobile phase B gradually changes from 80:20 to 20:

80. The volume ratio of mobile phase A to mobile phase B is 95:5 for 36-45 min.

2. The detection method for Revinaprine inhalation solution as described in claim 1, characterized in that, The concentration of revinapine in the inhalation solution sample was 5-60 μg / mL.

3. The detection method for Revinaprine inhalation solution as described in claim 1, characterized in that, The detection wavelength of the high-performance liquid chromatography method is 190-260 nm.

4. The detection method for Revinaprine inhalation solution as described in claim 1, characterized in that, The phosphate buffer solution includes at least one of sodium dihydrogen phosphate, disodium hydrogen phosphate, potassium dihydrogen phosphate, and dipotassium hydrogen phosphate.

5. The detection method for Revinaprine inhalation solution as described in claim 1, characterized in that, The concentration of phosphate in the phosphate buffer solution is 0.01-0.1 mol / L.

6. The detection method for Revinaprine inhalation solution as described in claim 1, characterized in that, The pH of the phosphate buffer solution is 2-5.

7. The detection method for Revinaprine inhalation solution as described in claim 1, characterized in that, The mobile phase flow rate for the high-performance liquid chromatography method is 0.5-1.5 mL / min, and the injection volume is 5-50 μL.

8. The detection method for Revinaprine inhalation solution as described in claim 1, characterized in that, The chromatographic column used in the high-performance liquid chromatography method is an octadecylsilane-bonded silica column, and the model of the octadecylsilane-bonded silica column is: column length 4.6 mm, inner diameter 250 mm, and particle size 5 μm.

9. The detection method for Revinaprine inhalation solution as described in claim 1, characterized in that, The column temperature for the high-performance liquid chromatography method is 45-55℃.

10. The detection method for Revinaprine inhalation solution as described in claim 1, characterized in that, The high-performance liquid chromatography method begins elution after treatment with a trapping column, which is an octylsilane-bonded silica column.

Images