Method for determining the release rate of cefoperazone hydrochloride sustained-release formulations

Abstract

This invention discloses a method for determining the release rate of cefoperazone hydrochloride sustained-release formulations. The method employs a reciprocating cylinder method to determine the release rate of the cefoperazone hydrochloride sustained-release formulation, comprising the following steps: dissolving the cefoperazone hydrochloride sustained-release formulation in a first phosphate buffer solution; replacing the first phosphate buffer solution with fresh solution at different time points A to obtain multiple dissolution solutions A; storing dissolution solutions A at 2-8°C; and determining the cefoperazone hydrochloride content in dissolution solutions A. The cefoperazone hydrochloride sustained-release formulation comprises cefoperazone hydrochloride sustained-release particles. The temperature of the first phosphate buffer solution is 37.0±0.5°C, the pH is 6.7-6.9, and the volume is 240-260 mL. This invention's method can accurately determine the release rate of cefoperazone hydrochloride in in vitro experiments.

Description

Technical Field

[0001] This invention relates to the field of pharmaceutical formulation analysis technology, specifically to a method for determining the release rate of cefoperazone hydrochloride sustained-release formulations. Background Technology

[0002] The molecular formula of cefoperazone hydrochloride (monohydrate) is C64-C ... 23 H 29 N5O8S2·HCl·H2O, with a molecular weight of 622.11, has the following structural formula:

[0003]

[0004] Cefcardine hydrochloride is a cephalosporin antibiotic primarily used to treat respiratory infections, otitis media, sinusitis, and skin and skin tissue infections caused by susceptible bacteria. Cefcardine hydrochloride granules are listed in the Japanese Pharmacopoeia JP18 and were first approved for marketing in Japan. They are immediate-release granules with a short half-life, requiring three daily doses. To reduce the frequency of administration, improve convenience, and maintain blood drug concentrations above the minimum inhibitory concentration (MIC) for an extended period, thereby increasing efficacy, it is necessary to convert cefcardine hydrochloride granules into a sustained-release formulation.

[0005] However, cefoperazone hydrochloride has poor solution stability in phosphate buffer at 37°C and pH 6.8, and is prone to degradation. This makes it impossible to simulate the release of cefoperazone hydrochloride sustained-release formulations under physiological conditions in vivo, and to accurately measure its release rate and release curve. Moreover, the release rate of cefoperazone hydrochloride sustained-release formulations measured using paddle or basket dissolution devices is inaccurate, thus hindering the research and development and dosage form transformation of cefoperazone hydrochloride sustained-release formulations. Summary of the Invention

[0006] The first objective of this invention is to provide a method for determining the release rate of cefoperazone hydrochloride sustained-release formulations, thereby solving at least one of the aforementioned technical problems.

[0007] According to a first aspect of the present invention, a method for determining the release rate of a cefoperazone hydrochloride sustained-release formulation is provided, comprising the following steps:

[0008] The cefcaptin hydrochloride sustained-release formulation was dissolved in a first phosphate buffer solution, and the first phosphate buffer solution was replaced at different time points A to obtain multiple dissolution solutions A.

[0009] Store the leachate A at 2-8℃;

[0010] Determine the cefcapine hydrochloride content in dissolution A;

[0011] The sustained-release formulation of cefcaptin hydrochloride includes sustained-release granules of cefcaptin hydrochloride, with a first phosphate buffer temperature of 37.0±0.5℃, a pH of 6.7-6.9, and a volume of 240-260mL.

[0012] This invention utilizes a reciprocating cylinder method for the dissolution of cefpodoxime hydrochloride sustained-release formulations. By replacing the first phosphate buffer during the dissolution process, the sample can continuously release and dissolve in fresh first phosphate buffer. The dissolution medium reaches the leakage conditions, and the dissolved solution A is transferred to 2-8℃ for storage. This increases the dissolution of cefpodoxime hydrochloride while preventing its degradation. This solves the problem of continuous degradation of cefpodoxime hydrochloride in pH 6.8 phosphate buffer negatively impacting detection results. It overcomes the technical limitation of inaccurate release rate determination in 37℃, pH 6.8 phosphate buffer, and resolves the long-standing but unsolved technical challenge of accurately determining the in vitro release rate of cefpodoxime hydrochloride. This represents a major breakthrough in the development of cefpodoxime hydrochloride sustained-release formulations and greatly promotes their development.

[0013] In some implementations, the first phosphate buffer has a pH of 6.8, i.e., pH 6.8 phosphate buffer.

[0014] In some implementations, the volume of the first phosphate buffer is 250 mL.

[0015] In some implementations, time point A is 2-14 hours, and the interval between two adjacent time points A does not exceed 4 hours.

[0016] In some implementations, time point A includes 4 hours, 5 hours, 6 hours, 8 hours, 10 hours, and 14 hours.

[0017] In some implementations, the reciprocating frequency of the reciprocating cylinder method can be 5-20 dpm.

[0018] In some implementations, the lower screen of the reciprocating drum method is 78-100 mesh.

[0019] In some embodiments, when the cefoperazone hydrochloride sustained-release formulation is replaced with a new primary phosphate buffer, the residence time is 0-60 seconds.

[0020] In some embodiments, when the cefoperazone hydrochloride sustained-release formulation is replaced with a new primary phosphate buffer, the draining time is 30-60 seconds.

[0021] In some implementations, the upper screen of the reciprocating drum method is 20-40 mesh.

[0022] In some embodiments, the first phosphate buffer solution is prepared by weighing 6.8 g of potassium dihydrogen phosphate and 0.893 g of sodium hydroxide, diluting it with purified water to 1000 mL, and adjusting the pH to 6.7-6.9 with phosphate solution or sodium hydroxide solution.

[0023] In some embodiments, the cefoperazone hydrochloride sustained-release formulation includes the following steps prior to the dissolution step in the first phosphate buffer:

[0024] The sustained-release formulation of cefcaptin hydrochloride was dissolved in hydrochloric acid solution. The hydrochloric acid solution was replaced at multiple time points B from 15 to 120 minutes to obtain dissolution solutions B at different time points B.

[0025] Store the leachate B at 2-8℃;

[0026] The content of cefoperazone hydrochloride in the dissolution solution B was determined and the cumulative release amount of the test solution B was calculated.

[0027] In some implementations, the concentration of the hydrochloric acid solution can be 0.08-0.12 mol / L.

[0028] In some embodiments, the concentration of the hydrochloric acid solution can be 0.10 mol / L. The 0.10 mol / L hydrochloric acid solution is prepared by measuring 9 mL of hydrochloric acid and diluting it with purified water to 1000 mL.

[0029] In some embodiments, the hydrochloric acid solution is at a temperature of 37.0 ± 0.5 °C and has a volume of 240-260 mL.

[0030] In some implementations, time point B is 0-2 hours, and the interval between two adjacent time points B does not exceed 1 hour.

[0031] In some implementations, time point B includes 15 minutes, 30 minutes, 60 minutes, and 120 minutes.

[0032] In some embodiments, the sustained-release formulation of cefcapine hydrochloride also includes cefcapine hydrochloride immediate-release granules.

[0033] In some embodiments, the content of cefoperazone hydrochloride is determined by high performance liquid chromatography (HPLC). The chromatographic conditions are as follows: the chromatographic column is a reversed-phase C18 column or an equivalent column; mobile phase A is a phosphate mixture, and mobile phase B is methanol; isocratic elution is used, and the volume ratio of mobile phase A to mobile phase B is (60-70):(40-30); wherein the phosphate mixture includes a second phosphate buffer, acetonitrile, and methanol, and the volume percentage of the second phosphate buffer, acetonitrile, and methanol is (61-79):(39-21):10; the second phosphate buffer includes 9-11 mmol / L sodium dihydrogen phosphate dihydrate and 4.5-5.5 mmol / L sodium 1-decanesulfonate.

[0034] In some embodiments, the second phosphate buffer solution can be prepared by weighing 1.56 g of sodium dihydrogen phosphate dihydrate and 1.22 g of sodium 1-decanesulfonate, and diluting them with water to 1000 mL.

[0035] In some implementations, the chromatographic conditions of the high-performance liquid chromatography (HPLC) satisfy at least one of the following conditions:

[0036] (1) The column temperature is 35-45℃;

[0037] (2) The detection wavelength is 263-267nm;

[0038] (3) The flow rate is 1.3-1.7 mL / min;

[0039] (4) The injection volume is 5-15 μL;

[0040] (5) The running time is 2.5-5.0 min.

[0041] In some embodiments, high-performance liquid chromatography (HPLC) is used to determine the content of cefoperazone hydrochloride, and the method includes the following steps:

[0042] Prepare a reference solution, and use high performance liquid chromatography to detect the reference solution, dissolution solution A and dissolution solution B respectively;

[0043] Based on the high-performance liquid chromatography (HPLC) results of the reference solution and the HPLC peak areas of dissolution A and dissolution B, the content of cefoperazone hydrochloride in dissolution A and dissolution B was calculated using the external standard method.

[0044] In some embodiments, when calculating the cefcardim hydrochloride content in dissolution A using the external standard method, the peak area of ​​dissolution A includes the peak area of ​​the main component of cefcardim hydrochloride and the peak area of ​​the degradation peak of cefcardim hydrochloride in pH 6.8 phosphate buffer. Including the degradation peak area in the calculation of the cefcardim hydrochloride content in the test solution A results in higher accuracy.

[0045] In some embodiments, the preparation method of the reference solution includes the following steps:

[0046] Accurately weigh 25 mg of cefcaptin hydrochloride reference standard, place it in a 50 mL volumetric flask, add 3 mL of methanol to dissolve it, dilute to the mark with methanol-water solution (50:50, V / V), shake well to obtain the reference standard stock solution;

[0047] Accurately measure 3 mL of the reference standard stock solution and place it in a 10 mL volumetric flask. Dilute to the mark with pH 6.8 phosphate buffer and shake well.

[0048] In some embodiments, the cefcaptin hydrochloride extended-release formulation is available in a strength of 150 mg (calculated as cefcaptin).

[0049] The method for determining the release rate of cefoperazone hydrochloride sustained-release formulation of the present invention not only provides a method for determining the release rate of cefoperazone hydrochloride sustained-release formulation, simulating the release of cefoperazone hydrochloride sustained-release formulation under physiological conditions in vivo, which is beneficial for studying its drug release curve, but also eliminates the sample accumulation problem that occurs during the basket method and paddle method dissolution of cefoperazone hydrochloride sustained-release formulation. Attached Figure Description

[0050] Figure 1 This is a liquid chromatogram of the reference solution from Example 1 of the present invention;

[0051] Figure 2 The liquid chromatogram of the dissolution solution B obtained in Example 1 of the present invention in 0.1 mol / L hydrochloric acid solution for 15 min is shown.

[0052] Figure 3 The liquid chromatogram of the dissolution solution A obtained in Example 1 of the present invention at pH 6.8 phosphate buffer for 4 hours is shown.

[0053] Figure 4 This is the liquid chromatogram of pH 6.8 phosphate buffer (without sample) in Example 1 of the present invention;

[0054] Figure 5 This is a diagram illustrating the dissolution process of the cefoperazone hydrochloride sustained-release formulation of Example 1 of the present invention;

[0055] Figure 6 This is a diagram illustrating the dissolution process of the cefoperazone hydrochloride sustained-release formulation of Example 2 of the present invention;

[0056] Figure 7 This is a diagram showing the dissolution process of the cefoperazone hydrochloride sustained-release formulation of Comparative Example 1 of the present invention in a 0.1 mol / L hydrochloric acid solution stage (paddle method - 50 rpm);

[0057] Figure 8This is a diagram showing the dissolution process of the cefoperazone hydrochloride sustained-release formulation of Comparative Example 1 of the present invention in the pH 6.8 phosphate buffer stage (paddle method - 50 rpm);

[0058] Figure 9 This is a bottom view of the cefoperazone hydrochloride sustained-release formulation of Comparative Example 1 of the present invention during the cleaning of the dissolution cup after the dissolution process (paddle method - 50 rpm);

[0059] Figure 10 This is a diagram showing the dissolution process of the cefoperazone hydrochloride sustained-release formulation of Comparative Example 2 of the present invention in the pH 6.8 phosphate buffer stage (paddle method - 100 rpm);

[0060] Figure 11 This is a bottom view of the cefoperazone hydrochloride sustained-release formulation of Comparative Example 2 of the present invention during the cleaning of the dissolution cup after the dissolution process (paddle method - 100 rpm);

[0061] Figure 12 The release curves of cefoperazone hydrochloride sustained-release formulations in Examples 1-6, Comparative Examples 1 and 2 of this invention are shown.

[0062] Figure 13 To verify the linear equation for the stability of test sample solutions with different release rates at pH 6.8 phosphate buffer. Detailed Implementation

[0063] The present invention will now be described in further detail with reference to the accompanying drawings, but the embodiments of the present invention are not limited thereto. The raw materials and reagents involved in the following embodiments are all commercially available.

[0064] The present invention discloses a method for determining the release rate of a cefoperazone hydrochloride sustained-release formulation, wherein the cefoperazone hydrochloride sustained-release formulation comprises cefoperazone hydrochloride sustained-release granules and cefoperazone hydrochloride immediate-release granules, and the release rate of the cefoperazone hydrochloride sustained-release formulation is determined using a reciprocating cylinder method, comprising the following steps:

[0065] S11. Cefcaptin hydrochloride sustained-release formulation was dissolved in 0.08-0.12 mol / L hydrochloric acid solution. The hydrochloric acid solution was replaced at multiple time points B from 15 to 120 minutes to obtain dissolution solutions B at different time points B. The temperature of the 0.08-0.12 mol / L hydrochloric acid solution was 37.0±0.5℃, and the volume was 240-260 mL.

[0066] S12. Store the dissolution solution B at 2-8℃.

[0067] S21. The residue of the cefoperazone hydrochloride sustained-release formulation after the hydrochloric acid solution dissolution process is dissolved in a first phosphate buffer solution. The first phosphate buffer solution is replaced with a new one at different time points A to obtain multiple dissolution solutions A. The temperature of the first phosphate buffer solution is 37.0±0.5℃, the pH is 6.7-6.9, and the volume is 240-260mL.

[0068] Store the leachate A at 2-8℃;

[0069] The content of cefcapine hydrochloride in leachate A and leachate B was determined;

[0070] The reciprocating frequency is 5-20 dpm, the lower screen is 78-100 mesh, the upper screen is 20-40 mesh, the residence time is 0-60 seconds, and the draining time is 30-60 seconds.

[0071] Time points B include 15 minutes, 30 minutes, 60 minutes, and 120 minutes; time points A include 4 hours, 5 hours, 6 hours, 8 hours, 10 hours, and 14 hours.

[0072] The following provides a detailed description of the experimental preparation and high-performance liquid chromatography method used in this invention.

[0073] I. Experimental Preparation

[0074] 1.1 Experimental Apparatus

[0075] The reciprocating cylinder dissolution apparatus was an Agilent B10-DIS, and the dissolution apparatus used for paddle / basket dissolution was a Huarong DS-1206AT; the electronic balance was a Sartorius SQP, the high performance liquid chromatographs were an Agilent 1260 Infinity II and a Thermo Fisher U3000; and the thermostatic shaker was a Shanghai Yiheng Technology DKZ-2.

[0076] 1.2 Experimental Reagents

[0077] Hydrochloric acid (AR), potassium dihydrogen phosphate (AR), sodium hydroxide (AR), sodium phosphate (AR), sodium dihydrogen phosphate dihydrate (AR), sodium 1-decanesulfonate (AR), acetonitrile (HPLC), methanol (HPLC), ultrapure water, purified water (degassed).

[0078] 1.3 Accessories

[0079] The reciprocating drum screen is available in 20 mesh, 40 mesh, 78 mesh, and 100 mesh sizes, and is made of polypropylene; the basket screen is available in 50 mesh, 100 mesh, and 200 mesh sizes.

[0080] 1.4 Samples

[0081] Cefcaptin hydrochloride sustained-release formulation, containing cefcaptin hydrochloride immediate-release granules and sustained-release granules, mixed according to the prescription ratio, approximately 1.77g / bag, specification 150mg (calculated as cefcaptin), sourced from Bemei R&D (Shenzhen) Co., Ltd.

[0082] 1.5 Reference Standard

[0083] The cefoperazone hydrochloride reference standard, with a content of 74.83% (calculated as cefoperazone), was obtained from Guangzhou Tonghui Pharmaceutical Co., Ltd.

[0084] 1.6 Solution Preparation Method

[0085] 0.1 mol / L hydrochloric acid solution: Measure 9 mL of hydrochloric acid, add 1000 mL of purified water, mix well, and the solution is ready.

[0086] First phosphate buffer: Weigh 6.8g of potassium dihydrogen phosphate and 0.896g of sodium hydroxide, add 1000mL of purified water to dissolve, and adjust the pH to 6.8 with phosphate solution or sodium hydroxide solution (hereinafter referred to as "pH6.8 phosphate buffer").

[0087] It should be noted that the above preparation method yields only one type of first phosphate buffer solution. The pH can be adjusted as needed to obtain first phosphate buffer solutions with different pH values. The present invention can also prepare first phosphate buffer solutions with pH 6.7 (hereinafter referred to as "pH 6.7 phosphate buffer solution") and first phosphate buffer solutions with pH 6.9 (hereinafter referred to as "pH 6.9 phosphate buffer solution") according to the above preparation method.

[0088] Second phosphate buffer: Weigh 1.56 g of sodium dihydrogen phosphate dihydrate and 1.22 g of sodium 1-decanesulfonate, add 1000 mL of ultrapure water to dissolve, and shake well.

[0089] Reference stock solution: Accurately weigh 25 mg of cefcaptin hydrochloride reference standard, place it in a 50 mL volumetric flask, add 3 mL of methanol to dissolve it, dilute to the mark with methanol-water solution (50:50, V / V), and shake well.

[0090] Reference solution: Accurately measure 3 mL of the reference stock solution and place it in a 10 mL volumetric flask. Dilute to the mark with pH 6.8 phosphate buffer and shake well.

[0091] II. High Performance Liquid Chromatography

[0092] This invention employs high-performance liquid chromatography (HPLC) to determine the content of cefoperazone hydrochloride. The chromatographic detection conditions are as follows:

[0093] The chromatographic column is a reversed-phase C18 column or a column with equivalent performance;

[0094] The column temperature is 35-45℃;

[0095] The detection wavelength is 263-267nm;

[0096] The flow rate is 1.3-1.7 mL / min;

[0097] The injection volume is 5-15 μL;

[0098] The running time is 2.5-5.0 minutes;

[0099] Mobile phase A is a phosphate mixture, and mobile phase B is methanol;

[0100] Isocratic elution was used, with a volume ratio of mobile phase A to mobile phase B of (60-70):(40-30).

[0101] The phosphate mixture comprises second phosphate buffer, acetonitrile, and methanol, with a volume percentage of (61-79):(39-21):10. Specifically, cefotaxime hydrochloride was determined by high-performance liquid chromatography (HPLC). Based on the HPLC results of the reference solution and the peak areas of dissolution solutions A and B, the cefotaxime hydrochloride content in dissolution solutions A and B was calculated using the external standard method.

[0102] III. Specific Test Content

[0103] Example 1

[0104] This embodiment provides a method for determining the release rate of cefoperazone hydrochloride sustained-release formulation, including the following steps:

[0105] The cefcaptin hydrochloride sustained-release formulation was dissolved in the dissolution medium (0.1 mol / L hydrochloric acid solution, pH 6.8 phosphate buffer) using a reciprocating dissolution apparatus according to the dissolution conditions in Table 1. The dissolution solution was collected at 15 min, 30 min, 1 h, 2 h; 4 h, 5 h, 6 h, 8 h, 10 h, and 14 h, respectively, filtered, and dissolution solution A and dissolution solution B were obtained; and stored at 2-8℃.

[0106] High-performance liquid chromatography (HPLC) was used to detect the dissolution solution A, dissolution solution B, and reference solution according to the chromatographic detection conditions in Table 2. The cumulative release of cefoperazone hydrochloride sustained-release formulation at multiple time points B and A was calculated by external standard method.

[0107] Table 1 Dissolution conditions

[0108]

[0109]

[0110] Table 2 Chromatographic Detection Conditions

[0111]

[0112] Example 2

[0113] This embodiment provides a method for determining the release rate of cefoperazone hydrochloride sustained-release formulation. The difference from Example 1 is that the lower sieve in this embodiment has a mesh size of 100.

[0114] The high-performance liquid chromatography method is the same as in Example 1.

[0115] Example 3

[0116] This embodiment provides a method for determining the release rate of cefcaptin hydrochloride sustained-release formulation. The difference from Example 1 is that the reciprocating rate is 10 dpm.

[0117] The high-performance liquid chromatography method is the same as in Example 1.

[0118] Example 4

[0119] This embodiment provides a method for determining the release rate of cefoperazone hydrochloride sustained-release formulation. The difference from Example 1 is that the reciprocating rate is 20 dpm.

[0120] The high-performance liquid chromatography method is the same as in Example 1.

[0121] Example 5

[0122] This embodiment provides a method for determining the release rate of cefcaptin hydrochloride sustained-release formulation. The difference from Example 1 is that pH 6.7 phosphate buffer is used instead of pH 6.8 phosphate buffer as the dissolution medium.

[0123] The high-performance liquid chromatography method is the same as in Example 1.

[0124] Example 6

[0125] This embodiment provides a method for determining the release rate of cefcaptin hydrochloride sustained-release formulation. The difference from Example 1 is that pH 6.9 phosphate buffer is used instead of pH 6.8 phosphate buffer as the dissolution medium.

[0126] The high-performance liquid chromatography method is the same as in Example 1.

[0127] Example 7

[0128] Based on Example 1, the effect of residence time on the medium exchange (pH 6.8 phosphate buffer and 0.1 mol / L hydrochloric acid solution) during the dissolution process was investigated under the condition of a reciprocating rate of 5-20 dpm.

[0129] Example 8

[0130] Based on Example 1, the effect of the dissolution medium (pH 6.8 phosphate buffer and 0.1 mol / L hydrochloric acid solution) on the draining time was investigated under the condition of a reciprocating rate of 5-20 dpm.

[0131] Comparative Example 1

[0132] This comparative example refers to the release rate method for enteric-coated preparations in the 2020 edition of the Chinese Pharmacopoeia. The release rate of cefoperazone hydrochloride extended-release preparation was determined using the second dissolution paddle method. The method for determining the release rate of cefoperazone hydrochloride extended-release preparation includes the following steps:

[0133] One packet of cefcaptin hydrochloride sustained-release formulation was placed in a dissolution vessel and dissolved using a paddle dissolution apparatus according to the dissolution conditions in Table 3. 750 mL of 0.1 mol / L hydrochloric acid solution was used as the dissolution medium for the 0.1 mol / L hydrochloric acid solution stage. After the hydrochloric acid solution stage, 250 mL of 0.2 mol / L sodium phosphate solution was added to adjust the pH of the dissolution medium to 6.8. The dissolution phenomenon was observed, and the dissolution solution was collected at 15 min, 30 min, 1 h, 2 h, 4 h, 5 h, 6 h, 8 h, 10 h, and 14 h. The solution was filtered, and the filtrate was stored at 2-8℃ to obtain the test solution.

[0134] The high-performance liquid chromatography method is the same as in Example 1.

[0135] Table 3. Dissolution conditions by paddle method

[0136]

[0137]

[0138] Comparative Example 2

[0139] The difference from Comparative Example 1 is that the paddle speed in this comparative example is set to 100 revolutions per minute.

[0140] The high-performance liquid chromatography method is the same as in Example 1.

[0141] Comparative Example 3

[0142] This comparative example uses the basket method to determine the release rate of cefoperazone hydrochloride sustained-release formulation. The method for determining the release rate of cefoperazone hydrochloride sustained-release formulation includes the following steps:

[0143] Using a basket dissolution apparatus, one bag of cefoperazone hydrochloride sustained-release formulation was placed in a dissolution vessel. 50-mesh, 100-mesh, and 200-mesh rotating baskets were used. 750 mL of 0.1 mol / L hydrochloric acid solution was used as the dissolution medium for the 0.1 mol / L hydrochloric acid solution stage. After the hydrochloric acid solution stage, 250 mL of 0.2 mol / L sodium phosphate solution was added to adjust the pH of the dissolution medium to 6.8, which served as the medium for the pH 6.8 phosphate buffer stage. The rotation speed was set to 100 rpm. The dissolution medium, sampling time, temperature, sampling volume, and replenishment volume were the same as those in Table 3. Dissolution phenomena were observed.

[0144] The high-performance liquid chromatography method is the same as in Example 1.

[0145] Comparative Example 4

[0146] The difference between this comparative example and Example 1 is that the reciprocating rate is 25 dpm.

[0147] The high-performance liquid chromatography method is the same as in Example 1.

[0148] In Example 1, see Figure 5 The dissolution process of cefoperazone hydrochloride sustained-release formulation shows that when dissolving using a 78-mesh sieve, the cefoperazone hydrochloride sustained-release formulation will not leak from the lower sieve. Figure 5 (The arrow indicates the location); In Example 2, see... Figure 6 When using a 100-mesh sieve for dissolution, the cefoperazone hydrochloride sustained-release formulation will not leak from the sieve (the arrow indicates the location). Furthermore, during the descent of the reciprocating cylinder in Examples 1 and 2, the dissolution medium can fill the reciprocating cylinder, thereby achieving smooth medium exchange and complete drainage of the dissolution medium during the reciprocating cylinder's water draining process.

[0149] In addition, the reciprocating rates in Examples 3 and 4 were 10 dpm and 20 dpm, respectively. During the dissolution of the cefoperazone hydrochloride sustained-release formulation, the dissolution medium could fill the reciprocating cylinder during its descent, ensuring smooth medium exchange and complete drainage of the dissolution medium during the dewatering process. Examples 5 and 6 used phosphate buffer solutions with different pH values ​​for dissolution and release.

[0150] In Example 7, at a reciprocating rate of 5 dpm, a residence time of 0 seconds is sufficient to completely fill the reciprocating cylinder with the dissolving medium, ensuring smooth medium exchange; at a reciprocating rate of 20 dpm, a residence time of 60 seconds is sufficient to completely fill the reciprocating cylinder with the dissolving medium, ensuring smooth medium exchange. In Example 8, at a reciprocating rate of 5 dpm, a draining time of 30 seconds is sufficient to completely drain the dissolving medium; at a reciprocating rate of 20 dpm, a draining time of 60 seconds is sufficient to completely drain the dissolving medium.

[0151] Comparative Example 1: Dissolution process using a paddle dissolution apparatus; results are shown in [Figure Number]. Figure 7and Figure 8 The cefoperazone hydrochloride sustained-release formulation severely accumulated at the bottom of the dissolution vessel (arrows indicate the accumulation site). After the dissolution process was completed, the bottom of the dissolution vessel was as follows: Figure 9 As shown, the cefcapine hydrochloride sustained-release formulation adheres to the bottom of the dissolution vessel, indicating that there is accumulation during the sample dissolution process, which affects the release behavior of this product.

[0152] In Comparative Example 2, the paddle speed was set to 100 rpm, and the dissolution process is described in [reference needed]. Figure 10 At a rotation speed of 100 rpm, cefoperazone hydrochloride sustained-release formulation significantly accumulated at the bottom of the dissolution vessel in the pH 6.8 phosphate buffer stage (arrows indicate the accumulation site); see Figure 11 Even when cleaning the dissolution cup, the sample could still be seen sticking to the bottom of the dissolution cup, indicating that increasing the paddle speed could not completely improve the sample accumulation phenomenon of cefcaptin hydrochloride sustained-release formulation during the dissolution process.

[0153] Comparative Example 3 used the basket method for detection. The cefcaptin hydrochloride sustained-release formulation would detach from the basket in a 50-mesh rotating basket, affecting the dissolution of cefcaptin hydrochloride; when dissolving in a 100-mesh rotating basket, the sample accumulated at the bottom of the basket, and the exchange of dissolution medium was not smooth; when dissolving in a 200-mesh rotating basket, the sample accumulated at the bottom of the rotating basket, and air bubbles adhered to the surface of the rotating basket, and the exchange of dissolution medium was not smooth.

[0154] Compared to Example 1, the reciprocating rate of Comparative Example 4 was 25 dpm. During the reciprocating motion, the exchange of media between the reciprocating cylinder and the dissolution cup was not smooth. The excessive reciprocating rate affected the dissolution of cefoperazone hydrochloride.

[0155] Taking Example 1 as an example, the high-performance liquid chromatography detection results are as follows: Figures 1-4 As shown, Figure 1 This is the liquid chromatogram of the reference solution. Figure 2 The image shows the liquid chromatogram of solution B, taken at 15 min in the 0.1 mol / L hydrochloric acid solution stage. Figure 3 This is the liquid chromatogram of dissolution solution A, taken at pH 6.8 phosphate buffer stage after 4 hours. Figure 4 This is a liquid chromatogram of pH 6.8 phosphate buffer (excluding the sample cefoperazone hydrochloride). Figure 3 It can be seen that impurity peaks appeared in the liquid chromatogram of dissolution A, which is attributed to the degradation of cefoperazone hydrochloride in pH 6.8 phosphate buffer. Therefore, when calculating the cumulative release of cefoperazone hydrochloride in dissolution A during the pH 6.8 phosphate buffer stage, the peak area is the sum of the peak area of ​​the main component of cefoperazone hydrochloride and the peak area of ​​the degradation peak (impurity peak). The cumulative release of cefoperazone hydrochloride was calculated, and the results are shown in Table 4. Release curves were plotted based on the release rate determination results of cefoperazone hydrochloride sustained-release formulations from Examples 1-6, Comparative Examples 1 and 2, respectively, and the results are as follows. Figure 12As shown.

[0156] Table 4. Results of Cumulative Release (%) of Cefcapine Hydrochloride Extended-Release Formulation

[0157]

[0158] As shown in Table 4, Comparative Example 1, after dissolving in 0.1 mol / L hydrochloric acid solution for 2 hours and then in pH 6.8 phosphate buffer solution for 12 hours, showed a cumulative release of no more than 40%; Comparative Example 2 showed a cumulative release of no more than 60%; Comparative Example 3, using the basket method, did not provide its cumulative release, but sample accumulation was severe; Comparative Example 4, compared to Example 1, had a reciprocating rate of 25 dpm, but did not provide its cumulative release, indicating that the excessive reciprocating rate affected dissolution. In contrast, the cumulative release of Examples 1 to 6 of this application was all greater than 85%, indicating that it was accurately detected under simulated in vivo physiological conditions, thus solving the problem of inaccurate in vitro detection of cefoperazone hydrochloride release.

[0159] from Figure 12 It can be seen that the cumulative release of cefpodoxime hydrochloride sustained-release formulation measured by the reciprocating cylinder dissolution apparatus is significantly higher than that measured by the paddle dissolution apparatus. Furthermore, compared to the paddle dissolution method, the reciprocating cylinder dissolution method for cefpodoxime hydrochloride sustained-release formulation not only eliminates the accumulation problem during the dissolution process and ensures smooth medium exchange, but also solves the problem of continuous degradation of cefpodoxime hydrochloride in pH 6.8 phosphate buffer by utilizing the structure of the reciprocating cylinder dissolution apparatus through multiple replacements (changing the dissolution medium) and low-temperature storage of the dissolution solution. This makes the determination results of the cefpodoxime hydrochloride release curve more accurate.

[0160] IV. Verification Experiment

[0161] This experiment investigated the stability of a sustained-release formulation of cefcapine hydrochloride soaked in pH 6.8 phosphate buffer, simulating the degradation of cefcapine hydrochloride with different release amounts under pH 6.8 phosphate buffer and 37.0±0.5℃ conditions for a certain period of time.

[0162] Weigh out 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 100% of the labeled amount (150 mg, calculated as cefoperazone) of the sustained-release cefoperazone hydrochloride preparation, respectively. Dissolve the cefoperazone hydrochloride in 1000 mL of pH 6.8 phosphate buffer solution and place in a water bath at 37.0 ± 0.5 °C with shaking. Samples are then taken at 0 h, 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, and 8 h, respectively. Filter the samples to obtain dissolution solutions with different theoretical release amounts and store them at 2-8 °C for testing.

[0163] The cefoperazone hydrochloride content in the dissolution solution at different release rates was calculated according to the liquid chromatography conditions in Table 2. The ratio of the remaining amount to the theoretical amount over time was plotted based on the test results of different theoretical release rates. The results are shown in Table 5. Figure 13 .

[0164] Table 5. Degradation of test solutions with different release rates at pH 6.8 phosphate buffer.

[0165]

[0166]

[0167]

[0168]

[0169] From Table 5 and Figure 13 It can be seen that test solutions with cefoperazone hydrochloride concentrations (calculated as cefoperazone) ranging from 10% to 100% of the labeled amount of this product are degraded in phosphate buffer at 37°C and pH 6.8. From the slope of the linear equation at each concentration level, it can be seen that the degradation rate of cefoperazone hydrochloride at each concentration level (linear equation slope) is similar. The average slope is -0.0375, which indicates that the degradation rate of cefoperazone hydrochloride is approximately 3.75% of the total degradation per hour.

[0170] Dissolution testing of cefpodoxime hydrochloride sustained-release formulations using a paddle dissolution apparatus has been inaccurate due to the continuous degradation of dissolved cefpodoxime hydrochloride in the pH 6.8 phosphate buffer stage. This application employs a reciprocating cylinder method to detect the cumulative release of cefpodoxime hydrochloride. By changing the dissolution medium, the sample reaches the leakage conditions in the dissolution medium, increasing the release of cefpodoxime hydrochloride. Furthermore, the dissolved cefpodoxime hydrochloride is transferred to a low-temperature environment within a certain time, significantly reducing continuous degradation and thus facilitating accurate release measurement. This method also mitigates the impact of continuous degradation of cefpodoxime hydrochloride in the pH 6.8 phosphate buffer stage. Therefore, the cumulative release measurement results of this application are more accurate, overcoming the technical bias of not being able to accurately measure release at 37℃ and pH 6.8 phosphate buffer.

[0171] The above descriptions are merely some embodiments of the present invention. Those skilled in the art can make various modifications and improvements without departing from the inventive concept of the present invention, and these all fall within the scope of protection of the present invention.

Claims

1. A method for determining the release rate of cefoperazone hydrochloride sustained-release formulations, characterized in that, The release rate of the cefoperazone hydrochloride sustained-release formulation was determined using the reciprocating cylinder method, including the following steps: The cefcaptin hydrochloride sustained-release formulation was dissolved in a first phosphate buffer solution, and the first phosphate buffer solution was replaced at different time points A to obtain multiple dissolution solutions A. Store the leachate A at 2-8℃; Determine the cefcapine hydrochloride content in dissolution A; The cefcapine hydrochloride sustained-release formulation comprises cefcapine hydrochloride sustained-release granules; the temperature of the first phosphate buffer is 37.0±0.5℃, the pH is 6.7-6.9, and the volume is 240-260mL.

2. The determination method according to claim 1, characterized in that, The time point A is 2-14 hours, and the interval between two adjacent time points A does not exceed 4 hours.

3. The determination method according to claim 2, characterized in that, The time point A includes 4 hours, 5 hours, 6 hours, 8 hours, 10 hours, and 14 hours.

4. The determination method according to claim 2, characterized in that, The reciprocating frequency of the reciprocating cylinder method is 5-20 dpm.

5. The determination method according to claim 4, characterized in that, The lower screen of the reciprocating cylinder method is 78-100 mesh.

6. The determination method according to claim 5, characterized in that, When the cefoperazone hydrochloride sustained-release formulation is replaced with a new primary phosphate buffer, the residence time is 0-60 seconds; and / or, The draining time is 30-60 seconds; and / or, The upper sieve for the reciprocating drum method is 20-40 mesh.

7. The determination method according to claim 6, characterized in that, The cefoperazone hydrochloride sustained-release formulation includes the following steps prior to the dissolution step in the first phosphate buffer: The sustained-release formulation of cefoperazone hydrochloride was dissolved in hydrochloric acid solution. The hydrochloric acid solution was replaced at multiple time points B from 15 to 120 minutes to obtain dissolution solutions B at different time points B. Store the leachate B at 2-8℃; Determine the cefoperazone hydrochloride content in dissolution solution B; The concentration of the hydrochloric acid solution was 0.08-0.12 mol / L, the temperature was 37.0±0.5℃, and the volume was 240-260 mL.

8. The determination method according to claim 7, characterized in that, The sustained-release formulation of cefoperazone hydrochloride also includes cefoperazone hydrochloride immediate-release granules; and / or... The selection range of time point B is 0-2 hours, and the interval between two adjacent time points B does not exceed 1 hour.

9. The determination method according to claim 6, characterized in that, The content of cefoperazone hydrochloride was determined by high performance liquid chromatography (HPLC). The chromatographic conditions included: The chromatographic column is a reversed-phase C18 column or a column with equivalent performance; Mobile phase A is a phosphate mixture, and mobile phase B is methanol; Isocratic elution was used, with a volume ratio of mobile phase A to mobile phase B of (60-70):(40-30). The phosphate mixture comprises a second phosphate buffer, acetonitrile, and methanol, wherein the volume percentage of the second phosphate buffer, acetonitrile, and methanol is (61-79):(39-21):

10. The second phosphate buffer comprises 9-11 mmol / L sodium dihydrogen phosphate dihydrate and 4.5-5.5 mmol / L sodium 1-decanesulfonate.

10. The determination method according to claim 9, characterized in that, The chromatographic conditions satisfy at least one of the following conditions: (1) The column temperature is 35-45℃; (2) The detection wavelength is 263-267nm; (3) The flow rate is 1.3-1.7 mL / min; (4) The injection volume is 5-15 μL; (5) The running time shall not be less than 2.5-5.0 min.

Images