Method for detecting related substances of rufinamide bulk drug

Abstract

The invention provides a detection method for determining related substances of a rufinamide raw material medicine, and belongs to the field of medicine analysis. The invention discloses a method for determining rufinamide bulk pharmaceutical chemicals and impurities thereof by adopting high performance liquid chromatography, which adopts a chromatographic column as a silica gel bonded octadecylsilane column, adopts a certain proportion of inorganic salt buffer solution-organic phase as a mobile phase, and adopts a gradient elution mode for separation and detection. According to the method for detecting the related substances of the rufinamide bulk drug, four impurities of the bulk drug can be detected at a time, the specificity is high, the precision is high, the repeatability is good, and the quality of the rufinamide bulk drug and the impurities of the rufinamide bulk drug can be effectively controlled.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical drug analysis, and in particular to a method for detecting related substances of rufinamide API. The method uses high performance liquid chromatography to perform qualitative or quantitative analysis on rufinamide and its impurities, thereby effectively controlling the quality of rufinamide API and its impurities. Background Art

[0002] Rufinamide, the English name is Rufinamide, the chemical name is: 1-(2,6-difluorobenzyl)-1H-1,2,3-triazole-4-carboxamide, and its molecular formula is C 10 H8RN4O, molecular weight is 238.

[0003] Rufinamide (hydrate) structure:

[0004] Rufinamide is a drug developed by Eisai, an American company. It was approved by the FDA for marketing in the United States in November 2008 for the adjunctive treatment of Lennox-Gastaut syndrome (LGS), a type of triazole derivative. Its chemical structure is completely different from existing anti-epileptic drugs, and its mechanism of action is through regulating voltage-gated sodium ion channels in the brain.

[0005] The impurities mentioned here are impurities introduced during the drug synthesis production process or impurities produced by degradation, including starting materials, intermediates, side reaction products, etc. Detection of related substances can control the quality and safety of drugs. In the process of synthesizing compounds, impurities may affect the purity and quality of drugs due to incomplete removal. These impurities and the degradation products produced are related substances. The study of related substances is one of the key projects in drug quality research, which affects the stability and safety of drugs. Therefore, it is necessary to strictly control the content of drug-related substances during drug production and storage. Therefore, the separation of rufinamide and other related substances and the ability to accurately quantify them have important practical significance in the quality control of the rufinamide synthesis process. Summary of the invention

[0006] The present invention provides a method for detecting related substances of rufinamide raw material medicine, thereby being able to quickly, effectively and accurately monitor the purity of rufinamide and achieve quality control of the final product raw material medicine.

[0007] The present invention provides a method for detecting related substances in rufinamide raw materials, which adopts high performance liquid chromatography, uses a chromatographic column with silica gel bonded with octadecylsilane as the stationary phase, uses a certain proportion of inorganic salt buffer solution as mobile phase A and an organic phase as mobile phase B, and performs isocratic elution.

[0008] The present invention provides a method for detecting related substances in rufinamide bulk drug, wherein the isocratic elution procedure is:

[0009] Preferably, the inorganic salt buffer solution is phosphate, specifically potassium dihydrogen phosphate, with a concentration of 0.02 mol / L and a pH value of 4.5.

[0010] Preferably, the organic phase is methanol.

[0011] Preferably, the chromatographic column provided is Apollo-C18 (4.6 mm×250 mm, 5 µm).

[0012] The separation and determination method of the present invention can be implemented according to the following method: (1) Take an appropriate amount of rufinamide sample and dissolve the sample in 60% methanol to prepare a sample solution containing 0.2 mg of rufinamide per 1 ml; (2) Set the mobile phase flow rate to 0.5-1.5 mL / min, preferably 1.0 mL / min; the detection wavelength to 210-250 nm, with the optimal detection wavelength being 220 nm; the column oven temperature to 20-50 °C, with the optimal column oven temperature being 30 °C.

[0013] The detection method of the present invention has strong specificity and high stability. The detection method has good reproducibility and can effectively separate rufinamide-related substances. The present invention solves the problem of separation and determination of rufinamide-related substances, thereby reducing the occurrence of side reactions, improving the yield and purity of the product, and ensuring the controllable quality of rufinamide. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is the HPLC chart of the blank solvent of rufinamide in Example 1; Figure 2 This is the HPLC chart of the rufinamide intermediate and its related substances in Example 1; Figure 3 This is the HPLC chart of the rufinamide intermediate and its related substances in Example 2; Figure 4 This is the HPLC chart of the rufinamide intermediate and its related substances in Example 3; Figure 5 This is the HPLC chart of the blank solvent of rufinamide in Example 4; Figure 6 This is the HPLC chart of the rufinamide intermediate and its related substances in Example 4. Specific implementation method: The following examples are used to further understand the present invention, but are not intended to limit the scope of this embodiment.

[0016] Example 1 Instruments and conditions High performance liquid chromatograph: Agilent 1260 InfinityII; Chromatographic column: Apollo-C18 (4.6 mm × 250 mm, 5 µm); Mobile phase A: 0.02 mol / L potassium dihydrogen phosphate buffer solution (weigh 2.72 g potassium dihydrogen phosphate, dissolve in water and dilute to 1000 ml, adjust pH to 4.5 with phosphoric acid); mobile phase B: methanol; elution according to the following gradient:

[0017] Flow rate: 1.0 mL / min; column temperature: 30°C; detection wavelength: 220 nm; injection volume: 20 μl; Take appropriate amount of rufinamide and its impurities, dissolve the sample in 60% methanol, and prepare a sample solution containing 0.2 mg / mL of rufinamide and 5 µg / mL of its impurities. Perform HPLC analysis under the above conditions and record the chromatogram. The results are shown in the attached Figure 1 and 2 , Figure 2 The chromatographic peak with a retention time of 10.840 min is rufinamide, and the other chromatographic peaks are the chromatographic peaks of various impurities of rufinamide.

[0018] Example 2 Instruments and conditions High performance liquid chromatograph: Agilent 1260 InfinityII; Chromatographic column: Apollo-C18 (4.6 mm × 250 mm, 5 µm); Mobile phase A: 0.02 mol / L potassium dihydrogen phosphate buffer solution (weigh 2.72 g potassium dihydrogen phosphate, dissolve in water and dilute to 1000 ml, adjust pH to 4.5 with phosphoric acid); mobile phase B: methanol; elution according to the following gradient:

[0019] Flow rate: 1.0 mL / min; column temperature: 30°C; detection wavelength: 220 nm; injection volume: 20 μl; Take appropriate amount of rufinamide and its impurities, dissolve the sample in 60% methanol, and prepare a sample solution containing 0.2 mg / mL of rufinamide and 5 µg / mL of its impurities. Perform HPLC analysis under the above conditions and record the chromatogram. The results are shown in the attached Figure 3 , Figure 3The chromatographic peak with a retention time of 10.855 min is rufinamide, and the other chromatographic peaks are the chromatographic peaks of various impurities of rufinamide.

[0020] Example 3 Instruments and conditions High performance liquid chromatograph: Agilent 1260 InfinityII; Chromatographic column: Apollo-C18 (4.6 mm × 250 mm, 5 µm); Mobile phase A: 0.02 mol / L potassium dihydrogen phosphate buffer solution (weigh 2.72 g potassium dihydrogen phosphate, dissolve in water and dilute to 1000 ml, adjust pH to 4.0 with phosphoric acid); mobile phase B: methanol; elution according to the following gradient:

[0021] Flow rate: 1.0 mL / min; column temperature: 30°C; detection wavelength: 220 nm; injection volume: 20 μl; Take appropriate amount of rufinamide and its impurities, dissolve the sample in 60% methanol, and prepare a sample solution containing 0.2 mg / mL of rufinamide and 5 µg / mL of its impurities. Perform HPLC analysis under the above conditions and record the chromatogram. The results are shown in the attached Figure 4 , Figure 4 The chromatographic peak with a retention time of 10.867 min is rufinamide, and the other chromatographic peaks are the chromatographic peaks of various impurities of rufinamide.

[0022] Example 4 Instruments and conditions High performance liquid chromatograph: Agilent 1260 InfinityII; Chromatographic column: Ultimate XB-C18 (4.6 mm × 250 mm, 5 µm); Mobile phase A: 0.02 mol / L potassium dihydrogen phosphate buffer solution (weigh 2.72 g potassium dihydrogen phosphate, dissolve in water and dilute to 1000 ml, adjust pH to 4.5 with phosphoric acid); mobile phase B: methanol; elution according to the following gradient:

[0023] Flow rate: 1.0 mL / min; column temperature: 30°C; detection wavelength: 220 nm; injection volume: 20 μl; Take appropriate amount of rufinamide and its impurities, dissolve the sample in 60% methanol, and prepare a sample solution containing 0.2 mg / mL of rufinamide and 5 µg / mL of its impurities. Perform HPLC analysis under the above conditions and record the chromatogram. The results are shown in the attached Figure 5 and 6 , Figure 6 The chromatographic peak with a retention time of 10.064 min is rufinamide, and the other chromatographic peaks are the chromatographic peaks of various impurities of rufinamide.

[0024] from Figure 1 - Figure 6 It is shown that the method of the present invention can separate rufinamide from its impurities and can accurately perform quantitative detection, thereby effectively controlling the product quality of rufinamide.

Claims

1. A method for separating related substances of rufinamide raw materials, using high performance liquid chromatography, the chromatographic column is a silica gel bonded octadecylsilane column, a certain proportion of inorganic salt buffer solution-organic phase as the mobile phase, and gradient elution is performed to separate rufinamide and various impurities.

2. The method for analyzing and detecting related substances of rufinamide bulk drug according to claim 1, characterized in that: The organic phase is selected from one of the following compounds: methanol and acetonitrile.

3. The method for analyzing and detecting related substances of rufinamide raw materials according to claim 1, characterized in that: The inorganic salt buffer solution is selected from one of the following inorganic salts: phosphate and perchlorate.

4. The method for analyzing and detecting related substances of rufinamide raw materials according to claim 1, characterized in that: The isocratic process is:

5. The method for analyzing and detecting related substances of rufinamide raw materials according to claim 1, characterized in that: The chromatographic column preferably has a length of 250 mm, a diameter of 4.6 mm, and a filler particle size of 3 μm.

6. The method for analyzing and detecting related substances of rufinamide bulk drug according to claims 1 and 3, characterized in that: The inorganic salt buffer solution is preferably phosphate, with an optimal concentration of 0.02 mol / L and a pH value of 4.

5.

7. The method for analyzing and detecting related substances of rufinamide bulk drug according to claims 1 and 2, characterized in that: The organic phase is preferably methanol.

8. The method for analyzing and detecting related substances of rufinamide bulk drug according to claim 1, characterized in that: The method comprises the following steps: ① setting the flow rate to 0.5-1.5 ml / min; ② setting the detection wavelength to 210-250 nm; ③ setting the column temperature to 20-40° C.; and ④ setting the injection volume to 5-20 μl.

9. The method for analyzing and detecting related substances of rufinamide raw materials according to claim 8, characterized in that: The chromatographic conditions are as follows: ① the flow rate is preferably 1.0 ml / min; ② the wavelength is preferably 220 nm; ③ the column temperature is preferably 30°C; ④ the injection volume is preferably 20 µl.

10. The method for analyzing related substances of rufinamide bulk drug according to claim 1, characterized in that: The impurities are:

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