Method for detecting N-oxide impurities in abiraterone acetate medicine

Abstract

The invention relates to the technical field of medicine detection, and discloses a method for detecting N-oxide impurities in abiraterone acetate medicine, which comprises the following steps: mixing an N-oxide impurity reference substance with acetonitrile to obtain a reference substance solution; the method comprises the following steps: mixing an abiraterone acetate medicine to be detected with acetonitrile to obtain a test solution; detecting the reference substance solution and the test solution by adopting a high performance liquid chromatography to obtain a chromatogram; in the detection process of the high performance liquid chromatography, mobile phases comprise a mobile phase A and a mobile phase B, the mobile phase A is acetonitrile, and the mobile phase B is water; and (4) analyzing by adopting an external standard method according to the chromatogram to obtain the content of the N-oxide impurity in the abiraterone acetate medicine. The method is high in detection sensitivity on the N-oxide impurities in the abiraterone acetate tablets, the method is good in durability, the N-oxide impurities in the abiraterone acetate tablets can be effectively controlled, and the controllability of the quality of the abiraterone acetate tablets is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of drug detection, and particularly to a method for detecting N-oxide impurities in abiraterone acetate drugs. Background Art

[0002] The main component of abiraterone acetate tablets is abiraterone acetate, and the excipients are lactose (monohydrate), microcrystalline cellulose, polyvinylpyrrolidone K30, sodium lauryl sulfate, croscarmellose sodium, silicon dioxide, and magnesium stearate. Under oxidation conditions, the N on the pyridyl group of abiraterone acetate will be oxidized to an N-oxy group, generating N-oxide impurities. This impurity shows an increasing trend during stability testing, and the N-oxide impurity contains a warning structure:

[0003] Currently, the gradient peaks in the related substance detection method of abiraterone acetate tablets interfere with the detection of N-oxide impurities, resulting in low detection sensitivity of N-oxide impurities. Therefore, there is an urgent need to provide a method for detecting N-oxide impurities in abiraterone acetate drugs to improve the detection sensitivity and ensure the controllability of the quality of drug preparations. Summary of the Invention

[0004] In view of this, the present invention provides a method for detecting N-oxide impurities in abiraterone acetate drugs, which has high sensitivity, can effectively control N-oxide impurities, and improves the controllability of the quality of abiraterone acetate drugs.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for detecting N-oxide impurities in abiraterone acetate drugs, comprising the following steps:

[0007] (1) Mixing an N-oxide impurity reference substance with acetonitrile to obtain a reference substance solution;

[0008] (2) Mixing the abiraterone acetate drug to be detected with acetonitrile to obtain a test sample solution;

[0009] (3) Detecting the reference substance solution and the test sample solution by high performance liquid chromatography to obtain a chromatogram; during the detection process of high performance liquid chromatography, the mobile phase includes mobile phase A and mobile phase B, the mobile phase A is acetonitrile, and the mobile phase B is water;

[0010] (4) Analyzing according to the chromatogram by the external standard method to obtain the content of N-oxide impurities in the abiraterone acetate drug.

[0011] Preferably, during the detection process of high performance liquid chromatography, the elution method is gradient elution.

[0012] Preferably, the gradient elution program is as follows:

[0013] Time (min) Mobile Phase A - Acetonitrile (%) Mobile Phase B - Water (%) 0 50 50 30 65 35

[0014] Preferably, during the detection by high performance liquid chromatography, the flow rate of the mobile phase is 0.45 - 0.55 mL / min.

[0015] Preferably, during the detection by high performance liquid chromatography, an ultraviolet absorption detector is used.

[0016] Preferably, during the detection by high performance liquid chromatography, the packing material of the chromatographic column is silica gel packing material bonded with a long alkyl chain containing a polar amide group.

[0017] Preferably, the particle size of the packing material is 3.5 - 5 μm.

[0018] Preferably, during the detection by high performance liquid chromatography, the column temperature is 10 - 20 °C.

[0019] Preferably, the concentration of the reference substance solution is 0.5 μg / mL.

[0020] Preferably, the concentration of the test sample solution is 10 mg / mL.

[0021] Preferably, the structural formula of the N - oxide impurity is:

[0022]

[0023] The present invention provides a method for detecting N - oxide impurities in abiraterone acetate drugs. Compared with the prior art, its beneficial effects are as follows:

[0024] The method of the present invention uses acetonitrile as the solvent for the reference substance and the test sample, and uses acetonitrile as mobile phase A and water as mobile phase B during the detection by high performance liquid chromatography, which can effectively separate the N - oxide impurities in abiraterone acetate drugs, improve the detection sensitivity of N - oxide impurities in abiraterone acetate drugs, has good method durability, can effectively control the N - oxide impurities in abiraterone acetate drugs, and improve the controllability of the quality of abiraterone acetate drugs. Brief Description of the Drawings

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0026] Figure 1 Chromatogram of the blank excipient solution of the present invention;

[0027] Figure 2 Chromatogram of the system suitability solution of the present invention;

[0028] Figure 3 Chromatogram of the test solution in Example 1 of the present invention;

[0029] Figure 4 Chromatogram of the test solution in Example 2 of the present invention;

[0030] Figure 5 Chromatogram of the test solution in Example 3 of the present invention;

[0031] Figure 6 Chromatogram of the test solution in Example 4 of the present invention;

[0032] Figure 7 Chromatogram of the test solution in Example 5 of the present invention;

[0033] Figure 8 Chromatogram of the test solution in Example 6 of the present invention;

[0034] Figure 9 Chromatogram of the reference solution in Examples 1 - 6 of the present invention;

[0035] Figure 10 Chromatogram of the undegraded blank excipient solution of the present invention;

[0036] Figure 11 Chromatogram of the undegraded test solution of the present invention;

[0037] Figure 12 Chromatogram of the acid - degraded blank excipient solution of the present invention;

[0038] Figure 13 Chromatogram of the acid - degraded test solution of the present invention;

[0039] Figure 14 Chromatogram of the base - degraded blank excipient solution of the present invention;

[0040] Figure 15 Chromatogram of the base - degraded test solution of the present invention;

[0041] Figure 16 Chromatogram of the oxidation - degraded blank excipient solution of the present invention;

[0042] Figure 17 Chromatogram of the oxidation - degraded test solution of the present invention;

[0043] Figure 18 Chromatogram of the high - temperature - degraded blank excipient solution of the present invention;

[0044] Figure 19 This is the chromatogram of the test sample solution degraded at high temperature according to the present invention;

[0045] Figure 20 This is the chromatogram of the blank excipient solution degraded by light according to the present invention;

[0046] Figure 21 This is the chromatogram of the test sample solution degraded by light according to the present invention. Detailed implementation manners

[0047] The present invention will be described below through specific examples. Those skilled in the art can understand that the following specific examples are only for illustrative purposes and do not limit the scope of the present invention in any way. In addition, in the following examples, unless otherwise specified, the reagents and equipment used are commercially available. If the specific processing conditions and methods are not clearly described in the following examples, the conditions and methods known in the art can be used for processing.

[0048] In the present invention, a method for detecting N-oxide impurities in abiraterone acetate drugs is provided, including the following steps:

[0049] (1) Mix the N-oxide impurity reference substance with acetonitrile to obtain a reference substance solution;

[0050] (2) Mix the abiraterone acetate drug to be detected with acetonitrile to obtain a test sample solution;

[0051] (3) Use high performance liquid chromatography to detect the reference substance solution and the test sample solution to obtain a chromatogram;

[0052] (4) According to the chromatogram, use the external standard method for analysis to obtain the content of N-oxide impurities in the abiraterone acetate drug.

[0053] In some embodiments of the present invention, the molecular formula of the N-oxide impurity is C 26 H 33 NO 3 , the molecular weight is 407.55, and the structural formula is:

[0054]

[0055] In the present invention, the N-oxide impurity reference substance is mixed with acetonitrile to obtain a reference substance solution.

[0056] In some embodiments of the present invention, the concentration of the reference substance solution is 0.5 μg / mL. Specifically, the N-oxide impurity reference substance is mixed with acetonitrile to prepare a reference substance solution.

[0057] In a specific embodiment of the present invention, the N-oxide impurity reference substance is obtained by purchasing from the market, and the manufacturer is Shenzhen Novak Technology Co., Ltd.

[0058] In the present invention, the abiraterone acetate drug to be detected is mixed with acetonitrile to obtain a test solution.

[0059] In some embodiments of the present invention, the abiraterone acetate drug can be abiraterone acetate tablets or abiraterone acetate raw materials, etc. The concentration of the test solution is 10 mg / mL. Specifically, taking abiraterone acetate tablets as an example, the abiraterone acetate tablets to be detected are ground into powder, added with acetonitrile and ultrasonicated, cooled to room temperature, fixed volume with acetonitrile, then filtered through a filter membrane, and the filtrate is taken as the test solution. Preferably, the subsequent filtrate after filtration is taken as the test solution.

[0060] In a specific embodiment of the present invention, in order to ensure the consistency of the experiment, the filter membrane used is 0.2 μm in pore size and 25 mm in diameter. However, in the actual operation process, the specifications and models of the filter membrane can be adjusted according to the situation, and no special limitation is imposed on this.

[0061] In the present invention, the reference solution and the test solution are detected by high performance liquid chromatography to obtain a chromatogram.

[0062] In some embodiments of the present invention, the chromatographic conditions of high performance liquid chromatography are as follows: the mobile phase includes mobile phase A and mobile phase B, wherein mobile phase A is acetonitrile and mobile phase B is water; the flow rate of the mobile phase is 0.45 - 0.55 mL / min, for example, it can be 0.45 mL / min, 0.48 mL / min, 0.50 mL / min, 0.52 mL / min, 0.55 mL / min, etc.; the column temperature is 10 - 20 °C, for example, it can be 10 °C, 12 °C, 15 °C, 18 °C, 20 °C, etc.; the elution method is gradient elution. It should be noted that the retention time of the N-oxide impurity is within 30 min. If only for qualitative detection of the N-oxide impurity, only gradient elution within 0 - 30 min is required. If for quantitative detection of the N-oxide impurity, the gradient elution time is generally set to 60 min, and the gradient elution program within 0 - 60 min is shown in Table 1:

[0063] Table 1

[0064] Time (min) Mobile Phase A - Acetonitrile (%) Mobile Phase B - Water (%) 0 50 50 30 65 35 32 95 5 50 95 5 52 50 50 60 50 50

[0065] In some embodiments of the present invention, the injection volume can be 20 μL, for example. No special limitation is imposed on this, and it can be appropriately increased or decreased according to the actual situation.

[0066] In some embodiments of the present invention, an ultraviolet absorption detector is used for chromatographic detection, and the detection wavelength can be selected, for example, as 254 nm. It should be noted that since the external standard method is adopted to calculate the content of N-oxide impurities in the present invention, adjusting the wavelength in this process will not affect the detection result. Therefore, the detection wavelength is not specifically limited and can be adjusted according to the actual situation.

[0067] In some embodiments of the present invention, the packing material of the chromatographic column is silica gel packing material bonded with a long alkyl chain containing a polar amide group, and the particle size of the packing material is 3.5 - 5 μm. Specifically, the chromatographic column can be, for example, Agilent ZORBAX Bonus-RP (4.6×250 mm, 5 μm), Agilent ZORBAX Bonus-RP (4.6×250 mm, 3.5 μm), or other chromatographic column models with equivalent efficiency.

[0068] It should be noted that through experimental research, it is found that if a common octadecylsilane-bonded silica chromatographic column (such as YMC-Pack Pro C18, 150×4.6, 3 μm or GL Sciences ODS-3, 250×4.6, 5 μm) or a pentafluorophenyl chromatographic column (such as HSS PFP 4.6×250 mm, 5 μm) is used, the separation effect between the N-oxide impurity in the test solution and the adjacent impurity is poor and does not meet the requirements.

[0069] In the present invention, according to the chromatogram, the external standard method is adopted for analysis to obtain the content of N-oxide impurities in abiraterone acetate drug.

[0070] In some embodiments of the present invention, the external standard single-point method is adopted for chromatographic analysis, which is not specifically limited, and it can be operated with reference to the conventional method.

[0071] Next, specific embodiments will be combined to clearly and completely describe the technical solutions in the present invention. The embodiments of this application are only for illustration. All other embodiments obtained by those skilled in the art without creative efforts fall within the scope of protection of the present invention.

[0072] Before performing the following embodiments, it is necessary to verify the applicability of the instrument and the chromatographic method through the system suitability solution, and verify that other components will not interfere with the detection of N-oxide impurities through the blank excipient solution. Among them, the blank excipient refers to the excipient for preparing the abiraterone acetate tablets to be detected, and the main component abiraterone acetate is not added to the blank excipient compared with the abiraterone acetate tablets to be detected.

[0073] Specifically, take the blank excipient of the abiraterone acetate tablets to be tested (equivalent to the prescription amount of 250 mg of abiraterone acetate), add 20 mL of acetonitrile, ultrasonicate for 5 minutes, cool to room temperature, make up to 25 mL with acetonitrile, shake well and filter with a filter membrane, take the filtrate to obtain a blank excipient solution.

[0074] Take N-oxide impurity reference substance and mix it with acetonitrile to obtain 10 μg / mL reference substance stock solution for standby use. Grind abiraterone acetate tablets (equivalent to 250 mg abiraterone acetate, purchased from Shanxi Zhendong Pharmaceutical Co., Ltd.) into powder, add 20 mL of acetonitrile, sonicate for 5 minutes, cool to room temperature, add 2.5 mL of reference substance stock solution, dilute to 25 mL with acetonitrile, shake well and filter with a filter membrane, take the filtrate to obtain a system suitability solution.

[0075] 20 μL of blank excipient solution and system suitability solution were measured and injected into the high performance liquid chromatograph respectively. The chromatographic conditions were the same as those in Example 1, and the chromatogram was recorded. Figure 1 and Figure 2 As shown, there is no substance interfering with the detection of N-oxide impurities in the blank auxiliary material, and the separation degree between the N-oxide impurity peak and the adjacent impurity peak in the chromatogram of the system suitability solution is ≥1.0, indicating that the instrument and chromatographic method used in the present invention have good applicability.

[0076] Example 1

[0077] This embodiment provides a method for detecting N-oxide impurities in abiraterone acetate drugs, and the specific steps are as follows:

[0078] (1) Mix the N-oxide impurity reference substance with acetonitrile to obtain a 0.5 μg / mL reference substance solution.

[0079] (2) Grind the abiraterone acetate tablets to be tested (equivalent to 250 mg of abiraterone acetate) into powder, add 20 mL of acetonitrile, sonicate for 5 min, cool to room temperature, dilute to 25 mL with acetonitrile, shake well, filter with a membrane, and take the filtrate to obtain a 10 mg / mL test solution.

[0080] (3) Take 20 μL of the reference solution and the test solution, inject them into the HPLC, record the chromatogram, and calculate the N-oxide impurity content by the peak area using the external standard method.

[0081] Among them, the chromatographic conditions of the high performance liquid chromatography are as follows:

[0082] The chromatographic column was Agilent ZORBAX Bonus-RP (4.6×250 mm, 5 μm), mobile phase A was acetonitrile, mobile phase B was water, the column temperature was 15 °C, the detection wavelength was 254 nm, the flow rate was 0.50 mL / min, the injection volume was 20 μl, and the elution program is shown in Table 1.

[0083] Example 2

[0084] This example was basically the same as Example 1, except that the flow rate of the mobile phase was 0.45 mL / min.

[0085] Example 3

[0086] This example was basically the same as Example 1, except that the flow rate of the mobile phase was 0.55 mL / min.

[0087] Example 4

[0088] This example was basically the same as Example 1, except that the column temperature was 10 °C.

[0089] Example 5

[0090] This example was basically the same as Example 1, except that the column temperature was 20 °C.

[0091] Example 6

[0092] This example was basically the same as Example 1, except that the chromatographic column was Agilent ZORBAX Bonus-RP (4.6×250 mm, 3.5 μm).

[0093] The chromatograms of the test solution in Examples 1-6 are shown in Figures 3 - 8 , and the chromatograms of the reference solution are shown in Figure 9 . It can be seen from the figures that the retention time of the N-oxide impurity peak was between 24-27 min, and the retention time of the impurity peak adjacent to the N-oxide was about 30 min, and good separation of the N-oxide could be achieved. The results of calculating the N-oxide impurity content by the external standard method based on the peak area are shown in Table 2.

[0094] Table 2

[0095] N - Oxide Impurity Detection Amount / % Example 1 0.0026 Example 2 0.0026 Example 3 0.0027 Example 4 0.0027 Example 5 0.0025 Example 6 0.0029

[0096] As can be seen from Table 2, by changing the chromatographic conditions of the high performance liquid chromatography, the detected amounts of N-oxide impurities in the final test solution were basically the same, indicating that the high performance liquid chromatography in the present invention had good durability; and the detected amount of N-oxide impurities by the method of the present invention could reach below 0.003%, having high sensitivity.

[0097] Comparative Example 1

[0098] This comparative example is basically the same as Example 1, and the only differences are the chromatographic column model, column temperature, and elution program. The chromatographic column is Agilent ZORBAX Bonus-RP (4.6×250 mm, 3.5 μm), the column temperature is 30 °C, the elution program is isocratic elution, the elution time is 25 min, the mobile phase A acetonitrile is 65%, and the mobile phase B water is 35%.

[0099] In this comparative example, the retention time of the N-oxide impurity peak is 14.340 min, and the N-oxide impurity peak has tailing.

[0100] Comparative Example 2

[0101] This comparative example is basically the same as Comparative Example 1, and the only difference is the elution program. The elution program is shown in Table 3.

[0102] Table 3

[0103] Time (min) Mobile Phase A - Acetonitrile (%) Mobile Phase B - Water (%) 0 50 50 30 80 20

[0104] In this comparative example, the retention time of the N-oxide impurity peak is 21.235 min, and there are other impurities at the tailing of the N-oxide impurity peak.

[0105] Comparative Example 3

[0106] This comparative example is basically the same as Comparative Example 2, and the only difference is the elution program. The elution program is shown in Table 4.

[0107] Table 4

[0108] Time (min) Mobile Phase A - Acetonitrile (%) Mobile Phase B - Water (%) 0 55 45 30 70 30

[0109] In this comparative example, the retention time of the N-oxide impurity peak is 19.941 min, and there are other impurities at the tailing of the N-oxide impurity peak.

[0110] Comparative Example 4

[0111] This comparative example is basically the same as Comparative Example 2, and the only difference is the elution program. The elution program is shown in Table 5.

[0112] Table 5

[0113] Time (min) Mobile Phase A - Acetonitrile (%) Mobile Phase B - Water (%) 0 60 40 30 70 30

[0114] In this comparative example, the retention time of the N-oxide impurity peak is 16.833 min, and there are other impurities at the tailing of the N-oxide impurity peak.

[0115] Comparative Example 5

[0116] This comparative example is basically the same as Comparative Example 4, except for the difference in column temperature, where the column temperature is 20 °C.

[0117] In this comparative example, the retention time of the N-oxide impurity peak is 17.790 min. Another impurity elutes after the N-oxide impurity, and the resolution is 1.35.

[0118] Comparative Example 6

[0119] This comparative example is basically the same as Comparative Example 4, except for the difference in column temperature, where the column temperature is 40 °C.

[0120] In this comparative example, the retention time of the N-oxide impurity peak is 15.989 min, and other impurities are included in the N-oxide impurity peak.

[0121] Comparative Example 7

[0122] This comparative example is basically the same as Comparative Example 4, except for the difference in flow rate, where the flow rate is 0.7 mL / min.

[0123] In this comparative example, the retention time of the N-oxide impurity peak is 12.392 min. Another impurity elutes after the N-oxide impurity and does not reach baseline separation.

[0124] Comparative Example 8

[0125] This comparative example is basically the same as Comparative Example 2, except for the difference in the elution program. The elution program is shown in Table 6.

[0126] Table 6

[0127]

[0128]

[0129] In this comparative example, the retention time of the N-oxide impurity peak is 17.386 min. Another impurity elutes after the N-oxide impurity and does not reach baseline separation.

[0130] Comparative Example 9

[0131] This comparative example is basically the same as Comparative Example 8, except for the difference in column temperature, where the column temperature is 15 °C.

[0132] In this comparative example, the retention time of the N-oxide impurity peak is 19.126 min. The N-oxide impurity and the adjacent impurity can reach baseline separation.

[0133] It should be noted that Comparative Examples 1-9 were directed to the detection of N-oxide impurities in the reference preparation of abiraterone acetate tablets (the reference preparation in the present invention is abiraterone acetate tablets in the reference preparation catalog, and the reference preparations in Comparative Examples 1-9 were subjected to an accelerated test for 3 months, and the accelerated conditions were temperature: 40°C ± 2°C; relative humidity: 75% ± 5%). The results showed that by reducing the column temperature and slowing down the gradient elution ability, the N-oxide impurity and the adjacent impurity could achieve baseline separation, which helped to improve the resolution between the N-oxide impurity and the adjacent impurity.

[0134] However, through experimental research, it was found that when abiraterone acetate tablets were placed under higher temperature conditions, more other degradation impurities would be generated after the N-oxide impurity peak, which would affect the separation effect. For example, when the reference preparation of abiraterone acetate tablets was placed at 60°C for 10 days and then chromatographically detected using the method of Comparative Example 9, the results showed that the retention time of the N-oxide impurity peak was 18.918 min, the N-oxide impurity had tailing, and the N-oxide impurity and the adjacent impurity behind it did not reach baseline separation. Therefore, the chromatographic conditions were further changed to conduct Comparative Examples 10-12. Among them, in Comparative Example 10, the abiraterone acetate tablets to be detected used the reference preparation placed at 60°C for 10 days, and in Comparative Examples 11-12, the abiraterone acetate tablets to be detected used the samples placed at 60°C for 30 days and the samples subjected to an accelerated test for 6 months (the accelerated conditions were temperature: 40°C ± 2°C; relative humidity: 75% ± 5%). In Comparative Examples 13-15, the abiraterone acetate tablets to be detected used the samples placed at 60°C for 30 days.

[0135] Comparative Example 10

[0136] This comparative example was basically the same as Comparative Example 9, and the only difference was the elution program. The elution program is shown in Table 7.

[0137] Table 7

[0138] Time (min) Mobile Phase A - Acetonitrile (%) Mobile Phase B - Water (%) 0 55 45 30 65 35

[0139] In this comparative example, the retention time of the N-oxide impurity peak was 22.450 min, the N-oxide impurity had tailing, and it was not separated from the adjacent impurity. Moreover, compared with Comparative Example 9, an unknown impurity was eluted after the N-oxide impurity.

[0140] Comparative Example 11

[0141] This comparative example was basically the same as Comparative Example 10, and the only difference was the column temperature, which was 10°C.

[0142] In this comparative example, the retention time of the N-oxide impurity peak was 23.564 min. The N-oxide impurity had tailing and was not separated from the adjacent impurity. However, compared with Comparative Example 10, the resolution between the N-oxide impurity and the unknown impurity behind it was improved to 0.95.

[0143] Comparative Example 12

[0144] This comparative example was basically the same as Comparative Example 11, and the only difference was the elution program. The elution program is shown in Table 8.

[0145] Table 8

[0146] Time (min) Mobile Phase A - Acetonitrile (%) Mobile Phase B - Water (%) 0 50 50 30 65 35

[0147] In this comparative example, the retention time of the N-oxide impurity peak was 27.258 min, and the resolution between the N-oxide impurity and the adjacent impurity was 1.08. Moreover, when using this method to detect abiraterone acetate tablets that had undergone a 6-month accelerated test, no other impurities were degraded after the N-oxide impurity, which did not affect the detection of the N-oxide impurity.

[0148] Comparative Example 13

[0149] This comparative example was basically the same as Comparative Example 12, and the only difference was the chromatographic column model, where the chromatographic column model was Agilent ZORBAX Bonus-RP (4.6×150 mm, 3.5 μm).

[0150] In this comparative example, the retention time of the N-oxide impurity peak was 17.667 min, and the separation effect between the N-oxide impurity and the adjacent impurity was slightly poor.

[0151] Comparative Example 14

[0152] This comparative example was basically the same as Comparative Example 13, and the only difference was the chromatographic column model, where the chromatographic column model was Agilent ZORBAX Bonus-RP (4.6×250 mm, 5 μm).

[0153] In this comparative example, the retention time of the N-oxide impurity peak was 25.273 min, and the N-oxide impurity was baseline-separated from the adjacent impurity.

[0154] Comparative Example 15

[0155] This comparative example was basically the same as Comparative Example 14, and the only difference was the column temperature, where the column temperature was 15°C.

[0156] In this comparative example, the retention time of the N-oxide impurity peak was 24.620 min, and the N-oxide impurity was baseline-separated from the adjacent impurity.

[0157] Comparative Examples 13-15 change the column specifications to examine durability. The results show that when the Agilent ZORBAX Bonus-RP (4.6×250 mm, 5 μm) column is used, the separation degree of N-oxide impurities and adjacent impurities reaches baseline separation, and the separation effect is good. At the same time, it was found in the experiment that when the column temperature is 10°C, if the instrument is operated for a long time, condensed water will appear in the column oven, causing the instrument to alarm, so it is preferred that the column temperature is greater than 10°C.

[0158] The changes in chromatographic conditions in Comparative Examples 1-15 and the chromatograms of the relevant parts are summarized in Table 9.

[0159] Table 9

[0160]

[0161]

[0162]

[0163] Test Example 1

[0164] This test example studied the degradation of abiraterone acetate tablets (source: Shanxi Zhendong Pharmaceutical Co., Ltd., hereinafter referred to as "this product") under different conditions. The experimental results are shown in Table 10.

[0165] Table 10

[0166]

[0167] Table 11

[0168]

[0169]

[0170] As shown in Table 10, Abiraterone acetate tablets are very easy to degrade to produce N-oxide impurities under oxidative degradation conditions, and a small amount of N-oxide impurities are degraded under high temperature, acid, alkali, and light conditions. Therefore, the N-oxide impurities in Abiraterone acetate tablets mainly come from oxidative degradation. Figures 10 - 21 It can be seen that under various degradation conditions, other impurities in the blank excipients and test samples did not interfere with the detection of N-oxide impurities, and the various degradation impurity peaks also did not interfere with the detection of N-oxide impurities.

[0171] Test Example 2

[0172] Three batches of abiraterone acetate tablets and two batches of reference preparations produced by Beijing Zhendong Guangming Pharmaceutical Research Institute Co., Ltd. were tested for storage stability, and the content of N-oxidation impurities was detected at intervals. The results are shown in Tables 12-14. Table 12 shows the test results of abiraterone acetate tablets placed at a temperature of 40±2°C and a relative humidity of 75±5%, Table 13 shows the test results of abiraterone acetate tablets placed at a temperature of 30±2°C and a relative humidity of 65±5%, and Table 14 shows the test results of abiraterone acetate tablets placed at a temperature of 25±2°C and a relative humidity of 60±5%. The test method adopts the method of Example 1.

[0173] Table 12

[0174]

[0175] Table 13

[0176]

[0177]

[0178] Table 14

[0179]

[0180] Note: “ / ” indicates that the corresponding time point was not detected.

[0181] As shown in Tables 12-14, during the stability test, the N-oxide impurities in the Abiraterone Acetate Tablets showed a trend of gradual growth over time, so it is necessary to detect the content of N-oxide impurities in the Abiraterone Acetate Tablets. In addition, the above results show that the detection method of the present invention can effectively detect the content of N-oxide impurities, has high detection sensitivity, and can effectively improve the controllability of the quality of Abiraterone Acetate Tablets.

[0182] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for detecting N-oxide impurities in abiraterone acetate drug, characterized in that: The following steps are involved: (1) mixing an N-oxide impurity reference substance with acetonitrile to obtain a reference substance solution; (2) mixing the abiraterone acetate drug to be tested with acetonitrile to obtain a test solution; (3) using high performance liquid chromatography to detect the reference solution and the test solution to obtain a chromatogram; during the high performance liquid chromatography detection process, the mobile phase includes a mobile phase A and a mobile phase B, the mobile phase A is acetonitrile, and the mobile phase B is water; (4) According to the chromatogram, an external standard method is used for analysis to obtain the content of N-oxide impurities in the abiraterone acetate drug.

2. The method for detecting N-oxide impurities in abiraterone acetate according to claim 1, characterized in that: During the high performance liquid chromatography detection process, the elution method is gradient elution.

3. The method for detecting N-oxide impurities in abiraterone acetate according to claim 2, characterized in that: The gradient elution procedure is as follows:

4. The method for detecting N-oxide impurities in abiraterone acetate according to claim 1, characterized in that: The flow rate of the mobile phase is 0.45-0.55 mL / min.

5. The method for detecting N-oxide impurities in abiraterone acetate medicine according to claim 1, characterized in that: In the high performance liquid chromatography detection process, an ultraviolet absorption detector is used.

6. The method for detecting N-oxide impurities in abiraterone acetate according to claim 1, characterized in that: During the high performance liquid chromatography detection process, the filler of the chromatographic column is a silica gel filler bonded with a long alkyl chain containing a polar amide group.

7. The method for detecting N-oxide impurities in abiraterone acetate according to claim 6, characterized in that: The particle size of the filler is 3.5-5 μm.

8. The method for detecting N-oxide impurities in abiraterone acetate according to claim 1, characterized in that: During the high performance liquid chromatography detection process, the column temperature is 10-20°C.

9. The method for detecting N-oxide impurities in abiraterone acetate according to claim 1, characterized in that: The concentration of the reference solution is 0.5 μg / mL; The concentration of the test solution is 10 mg / mL.

10. The method for detecting N-oxide impurities in abiraterone acetate drugs according to any one of claims 1 to 9, characterized in that: The structural formula of the N-oxide impurity is:

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