Method for detecting related substances of lisdexamphetamine dimesylate capsule

Abstract

The invention belongs to the field of pharmaceutical analysis, and particularly discloses a method for detecting related substances of a lisdexamphetamine dimesylate capsule, which establishes an impurity extraction method suitable for the characteristics of capsule contents, and effectively separates known impurities, unknown impurities and effective components of the capsule by combining high performance liquid chromatography conditions. The detection method is simple and efficient, few types of control samples are used, the specificity is good, and the method is a convenient and efficient method for detecting the related substances of the lisdexamphetamine dimesylate capsule.

Description

Technical Field

[0001] The invention belongs to the field of drug analysis, and particularly relates to a method for detecting related substances of lisdexamfetamine dimesylate capsules. Background Art

[0002] Lisdexamfetamine Dimesylate Capsules are a drug produced by Shire (now Takeda) under the trade name Vyvanse. The drug is a sympathomimetic drug of the central nervous system and is used to treat attention deficit hyperactivity disorder (ADHD) and binge eating disorder (BED). The capsules include lisdexamfetamine Dimesylate, excipients and empty capsules. The active substance lisdexamfetamine Dimesylate is a prodrug. After oral administration, it is converted from a prodrug with no therapeutic effect to d-amphetamine (d-AMP) to produce a drug effect.

[0003] The structure of lisdexamfetamine dimesylate is shown below:

[0004]

[0005] The study of related substances is one of the key projects in drug quality research. The related substances of preparations mainly include material impurities introduced by raw materials and excipients, process impurities generated during the process, and degradation products during storage.

[0006] Patent CN201910276752.3 reports a high-performance liquid phase analysis method for impurities in lisdexamfetamine dimesylate and its intermediates. The impurities analyzed by this method are:

[0007]

[0008] Unlike the APIs that this patent focuses on, the impurities in lisdexamfetamine dimesylate capsules are more complex. Due to the presence of excipients, the extraction and separation of impurities is more difficult. The multiple impurity situation also poses a greater challenge to the specificity of the analytical method.

[0009] The currently known impurities in lisdexamfetamine dimesylate capsules include (S)-methyl-phenethylamine (abbreviated as dextroamphetamine), (S)-2,6-diamino-N-[(R)-1-hydroxy-3-phenylpropyl-2-yl]hexanamide (abbreviated as impurity A), and (2R)-2,6-diamino-N-[(1S)-1-methyl-2-phenylethyl]hexanamide (abbreviated as impurity C).

[0010] In the accelerated test (40℃ / RH75%, placed with packaging) of lisdexamfetamine dimesylate capsules (formulated materials include fillers, disintegrants, lubricants, hollow capsule shells, etc.), 4 unknown impurities were unexpectedly found. These unknown impurities are all unique impurities of the preparation and require specific extracts. At the same time, due to the large number of impurities, the main component peak and the impurity peak adjacent to it are not easy to separate, and the specificity challenge is relatively large. How to fully extract the impurities and effectively separate the known impurities, unknown impurities and the effective ingredients of the capsules in the chromatogram is of great significance to improving the drug process level, improving the drug quality level and safety performance.

[0011] Therefore, it is necessary to establish a related substance detection method for lisdexamfetamine dimesylate capsules to control the known impurities and unknown impurities in lisdexamfetamine dimesylate capsules so as to effectively control its quality. Summary of the invention

[0012] In order to effectively control the quality of lisdexamfetamine dimesylate capsules, the present invention provides a method for detecting related substances of lisdexamfetamine dimesylate capsules, which adopts high performance liquid chromatography for detection, and the specific steps are as follows:

[0013] a. Preparation of test solution: Take the contents of lisdexamfetamine dimesylate capsules, treat with solution, filter, and take the filtrate to obtain;

[0014] b. Preparation of system suitability solution: Take dextroamphetamine reference substance, impurity A reference substance, and impurity C reference substance, add solvent to dissolve, and obtain impurity stock solution; take lisdexamfetamine dimesylate reference substance, add impurity stock solution and solvent to mix, and obtain;

[0015] c. Take the test solution and system suitability solution separately and inject them into the chromatograph. The chromatographic conditions are as follows:

[0016] Chromatographic column: octadecylsilane bonded silica gel as filler; mobile phase: sulfonate solution with pH of 2.0-4.0 as mobile phase A, acetonitrile as mobile phase B; detection wavelength of 200-219nm; gradient elution program:

[0017]

[0018] Furthermore, the solution treatment is specifically as follows: adding alkaline alcohol solution to the content to dissolve, then adding acid solution to neutralize, adding phosphoric acid solution to shake well and set to volume.

[0019] Furthermore, the alkaline alcohol solution is one or more of sodium hydroxide methanol solution, sodium hydroxide ethanol solution, potassium hydroxide methanol solution, potassium hydroxide ethanol solution, sodium carbonate methanol solution, sodium bicarbonate methanol solution, sodium phosphate methanol solution, sodium carbonate ethanol solution, sodium bicarbonate ethanol solution, sodium phosphate ethanol solution, concentrated ammonia methanol solution, and concentrated ammonia ethanol solution; the concentration of the alkaline alcohol solution is 0.2-0.8 mol / L.

[0020] Furthermore, the concentration of the phosphoric acid solution is 0.1%-0.5%; the acid solution is one or more of hydrochloric acid solution, sulfuric acid solution, formic acid solution, trifluoroacetic acid solution, and phosphoric acid solution; the concentration of the acid solution is 0.2-0.8 mol / L.

[0021] Furthermore, the solvent in step b is phosphoric acid solution-methanol; the volume ratio of the phosphoric acid solution-methanol is 60:40, and the concentration of the phosphoric acid solution is 0.1% to 1%; the concentration of lisdexamfetamine dimesylate in the system suitability solution is 1-5 mg / mL, and the concentrations of dextroamphetamine, impurity A, and impurity C are all 1 to 10 μg / mL.

[0022] Furthermore, the sulfonate in step c is one or more of sodium pentane sulfonate, sodium hexane sulfonate, sodium heptane sulfonate, sodium octane sulfonate, sodium decane sulfonate, and sodium dodecyl sulfonate, preferably sodium octane sulfonate; and the concentration of the sulfonate solution is 0.01-0.05 mmol / L, preferably 0.02-0.04 mmol / L.

[0023] Furthermore, in the chromatographic conditions, the chromatographic column is Phenomenex Gemini C18, GL science Inertsil ODS-3 or YMC-Pack ODS-AQ, with specifications of 4.6×150 mm, 5 μm; flow rate is 0.8-1.2 mL / min, column temperature is 30-50° C., and injection volume is 20-50 μL.

[0024] Furthermore, the contents of the lisdexamfetamine dimethanesulfonate capsules are the contents of the lisdexamfetamine dimethanesulfonate capsules placed under high temperature conditions (≥25°C) or the contents of the lisdexamfetamine dimethanesulfonate capsules placed under high humidity conditions (≥RH40%); the related impurities detected by the detection method include impurity A, impurity C, dextroamphetamine and unknown impurities 1-4.

[0025] Furthermore, the structural formula of the impurity A is:

[0026]

[0027] The structural formula of the impurity C is:

[0028]

[0029] Molecular ion peak of the unknown impurity 1 [M+H] + is 336.08, and the molecular weight is 335.08;

[0030] Molecular ion peak of the unknown impurity 2 [M+H] + is 322.12, and the molecular weight is 321.12;

[0031] The molecular ion peak of the unknown impurity 3 [M+H] + is 292.08, and the molecular weight is 291.08;

[0032] The molecular ion peak of the unknown impurity 4 [M+H] + The molecular weight is 292.08 and 291.08.

[0033] Furthermore, in the chromatogram of the test solution obtained by the detection method, impurity A, impurity C, and dextroamphetamine peak at corresponding positions of the reference substance; unknown impurity 1, unknown impurity 2, dextroamphetamine, unknown impurity 3, and unknown impurity 4 peak in sequence.

[0034] Further, the gradient elution procedure is:

[0035]

[0036] or:

[0037]

[0038] or:

[0039]

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] 1. The detection method of the present invention establishes an impurity extraction method suitable for the characteristics of the contents of lisdexamfetamine dimethanesulfonate capsules, and the impurity extraction is sufficient; the known impurities, unknown impurities and capsule effective ingredients are effectively separated by high performance liquid chromatography analysis combined with gradient elution, thereby achieving the purpose of effectively controlling the quality of lisdexamfetamine dimethanesulfonate capsules.

[0042] 2. The detection method of the present invention is simple, efficient, highly specific, and uses fewer types of control samples. It is a very convenient method for detecting related substances of lisdexamfetamine dimesylate capsules and has practical promotion and application value.

[0043] Obviously, according to the above contents of the present invention, in accordance with common technical knowledge and customary means in the art, without departing from the above basic technical ideas of the present invention, other various forms of modification, replacement or change may be made.

[0044] The above contents of the present invention are further described in detail below through specific implementation methods in the form of embodiments. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following examples. All technologies realized based on the above contents of the present invention belong to the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is the sample solution spectrum of Example 1;

[0046] Figure 2 This is the solution spectrum of the system suitability of Example 2;

[0047] Figure 3 This is the sample solution spectrum of Example 2;

[0048] Figure 4 This is the sample solution spectrum of Example 3;

[0049] Figure 5 This is the sample solution spectrum of Example 4;

[0050] Figure 6 This is the sample solution spectrum of Example 5;

[0051] Figure 7 This is the sample solution spectrum of Example 6;

[0052] Figure 8 This is the sample solution spectrum of Comparative Example 1;

[0053] Fig. 9 This is the sample solution spectrum of Comparative Example 2;

[0054] Fig.10 This is the sample solution spectrum of Comparative Example 3. DETAILED DESCRIPTION

[0055] Embodiment 1 Detection of related substances of lisdexamfetamine dimesylate capsules

[0056] (1) The test solution is prepared as follows:

[0057] Take 0.2g of the contents of lisdexamfetamine dimesylate capsules (equivalent to 37.5mg of lisdexamfetamine dimesylate) under high temperature / high humidity conditions (40℃ / RH75%, placed with packaging for 6 months), place it in a 25mL volumetric flask, add 10ml of 0.2mol / L potassium hydroxide methanol solution, shake for 5 minutes, then neutralize with 0.2mol / L formic acid solution, and finally dilute to the scale with 0.2% phosphoric acid solution, shake well, filter, and take the filtrate to obtain the test solution.

[0058] (2) System suitability solution:

[0059] A. Accurately weigh the dextroamphetamine reference substance, impurity A reference substance, and impurity C reference substance, add 0.2% phosphoric acid solution-methanol with a volume ratio of 60:40 to dissolve and quantitatively dilute to prepare an impurity stock solution containing 45 μg of dextroamphetamine, impurity A, and impurity C per 1 mL;

[0060] B. Take 15 mg of lisdexamfetamine dimesylate reference substance, place it in a 10 mL volumetric flask, accurately add 1 mL of stock solution, shake well, and make up to volume with 0.2% phosphoric acid solution-methanol solution in a volume ratio of 60:40 to prepare a system suitability solution containing impurity C, impurity A, dextroamphetamine and lisdexamfetamine dimesylate;

[0061] (3) Inject the system suitability solution and the test solution into the liquid chromatograph and record the chromatogram; the chromatographic conditions are as follows: chromatographic column: Phenomenex Gemini C18, 4.6×150 mm, 5 μm; mobile phase: sodium pentane sulfonate with a pH of 2.0 and a concentration of 0.02 mmol / L as mobile phase A, acetonitrile as mobile phase B, and detection wavelength of 219 nm; column temperature of 40°C; injection volume of 20 μL; flow rate: 1.0 mL / min; gradient elution program:

[0062]

[0063] The obtained chromatogram of the test solution was compared with the chromatograms of the solvent blank solution and the excipient blank solution obtained under the same chromatographic conditions, as well as the chromatogram of the system suitability solution, and the peak positions of dextroamphetamine, impurity A, impurity C, and unknown impurities 1-4 in the chromatogram of the test solution were located. Figure 1 From the spectrum, it can be seen that the detection method can effectively separate the active ingredient, impurity A, impurity C, unknown impurity 1, unknown impurity 2, dextroamphetamine, unknown impurity 3, and unknown impurity 4 of lisdexamfetamine dimesylate capsules.

[0064] Embodiment 2 Detection of related substances of lisdexamfetamine dimesylate capsules

[0065] (1) The test solution is prepared as follows:

[0066] Take 0.2 g of the content of lisdexamfetamine dimethanesulfonate capsules (equivalent to 37.5 mg of lisdexamfetamine dimethanesulfonate) under high temperature / high humidity conditions (i.e. 40°C / RH75%, placed with packaging for 6 months), place it in a 25 mL volumetric flask, add 80 μg each of dextroamphetamine, impurity A, and impurity C, add 10 mL of 0.5 mol / L sodium hydroxide methanol solution, shake for 30 minutes, neutralize with 0.5 mol / L hydrochloric acid solution, dilute to the scale with 0.3% phosphoric acid solution, shake well, filter, and take the filtrate to obtain the test solution.

[0067] (2) System suitability solution:

[0068] A. Take dextroamphetamine reference substance, impurity A reference substance, and impurity C reference substance respectively, accurately weigh them, dissolve them in 0.3% phosphoric acid solution-methanol with a volume ratio of 60:40, and quantitatively dilute them to prepare an impurity stock solution containing 45 μg of dextroamphetamine, impurity A, and impurity C per 1 mL;

[0069] B. Take 15 mg of lisdexamfetamine dimesylate reference substance, place it in a 10 mL volumetric flask, accurately add 1 mL of stock solution, shake well, and make up to volume with 0.3% phosphoric acid solution-methanol solution in a volume ratio of 60:40 to prepare a system suitability solution containing impurity C, impurity A, dextroamphetamine and lisdexamfetamine dimesylate;

[0070] (3) Inject the system suitability solution and the test solution into the liquid chromatograph and record the chromatogram; the chromatographic conditions are as follows: chromatographic column: GL science Inerstil ODS-3, 4.6×150 mm, 5 μm; mobile phase: sodium octane sulfonate with a pH of 3.0 and a concentration of 0.03 mmol / L as mobile phase A, acetonitrile as mobile phase B, and detection wavelength of 215 nm; column temperature of 50°C; injection volume of 20 μL; flow rate: 1.0 mL / min; gradient elution program:

[0071]

[0072] The obtained chromatogram of the test solution was compared with the chromatograms of the solvent blank solution and the excipient blank solution obtained under the same chromatographic conditions, as well as the chromatogram of the system suitability solution, and the peak positions of dextroamphetamine, impurity A, impurity C, and unknown impurities 1-4 in the chromatogram of the test solution were located. Figure 2 and Figure 3 From the spectrum, it can be seen that after the content of related substances in the test solution increases, the detection method can still effectively separate the active ingredients, impurity A, impurity C, unknown impurity 1, unknown impurity 2, dextroamphetamine, unknown impurity 3, and unknown impurity 4 of lisdexamfetamine dimesylate capsules.

[0073] Embodiment 3 Detection method of related substances of lisdexamfetamine dimesylate capsule

[0074] (1) The test solution is prepared as follows:

[0075] Take 0.2 g (equivalent to 37.5 mg of lisdexamfetamine dimethanesulfonate) of lisdexamfetamine dimethanesulfonate capsules under high temperature / high humidity conditions (i.e. 40°C / RH75%, placed with packaging for 6 months), place in a 25 mL volumetric flask, add 10 mL of 0.3 mol / L sodium hydroxide ethanol solution, shake for 10 minutes, neutralize with 0.3 mol / L hydrochloric acid solution, dilute to the scale with 0.4% phosphoric acid solution, shake well, filter, and take the filtrate to obtain the test solution.

[0076] (2) System suitability solution:

[0077] A. Take dextroamphetamine reference substance, impurity A reference substance, and impurity C reference substance respectively, accurately weigh them, dissolve them in 0.4% phosphoric acid solution-methanol at a volume ratio of 60:40, and quantitatively dilute them to prepare an impurity stock solution containing about 45 μg of dextroamphetamine, impurity A, and impurity C per 1 mL;

[0078] B. Take 15 mg of lisdexamfetamine dimesylate reference substance, place it in a 10 mL volumetric flask, accurately add 1 mL of stock solution, shake well, and make up to volume with 0.4% phosphoric acid solution-methanol solution in a volume ratio of 60:40 to prepare a system suitability solution containing impurity C, impurity A, dextroamphetamine and lisdexamfetamine dimesylate;

[0079] (3) Inject the system suitability solution and the test solution into the liquid chromatograph and record the chromatogram; the chromatographic conditions are as follows: chromatographic column: GL science Inerstil ODS-3, 4.6×150 mm, 5 μm; mobile phase: sodium octane sulfonate with a pH of 4.0 and a concentration of 0.02 mmol / L as mobile phase A, acetonitrile as mobile phase B, detection wavelength of 205 nm; column temperature of 45°C; injection volume of 20 μL; flow rate: 1.0 mL / min; gradient elution program:

[0080]

[0081] The obtained chromatogram of the test solution was compared with the chromatograms of the solvent blank solution and the excipient blank solution obtained under the same chromatographic conditions, as well as the chromatogram of the system suitability solution, and the peak positions of dextroamphetamine, impurity A, impurity C, and unknown impurities 1-4 in the chromatogram of the test solution were located. Figure 4 From the spectrum, it can be seen that the detection method can effectively separate the active ingredient of lisdexamfetamine dimesylate, impurity A, impurity C, unknown impurity 1, unknown impurity 2, dextroamphetamine, unknown impurity 3, and unknown impurity 4.

[0082] Embodiment 4 Detection method of related substances of lisdexamfetamine dimesylate capsule

[0083] (1) The test solution is prepared as follows:

[0084] Take 0.2g of the contents of lisdexamfetamine dimesylate capsules (equivalent to 37.5mg of lisdexamfetamine dimesylate) placed under high temperature / high humidity conditions (i.e., placed at 30°C / RH65% for 12 months), place in a 25mL volumetric flask, add 80μg each of dextroamphetamine, impurity A, and impurity C, add 10mL of 0.1mol / L sodium carbonate methanol solution, shake for 20 minutes, neutralize with 0.3mol / L hydrochloric acid solution, dilute to scale with 0.5% phosphoric acid solution, shake well, filter, and take the filtrate to obtain the test solution. (2) System suitability solution:

[0085] A. Take dextroamphetamine reference substance, impurity A reference substance, and impurity C reference substance respectively, accurately weigh them, dissolve them in 0.5% phosphoric acid solution-methanol with a volume ratio of 60:40, and quantitatively dilute them to prepare an impurity stock solution containing 45 μg of dextroamphetamine, impurity A, and impurity C per 1 mL;

[0086] B. Take 15 mg of lisdexamfetamine dimethanesulfonate reference substance, place it in a 10 mL volumetric flask, accurately add 1 mL of stock solution, shake well, and make up to volume with 0.5% phosphoric acid solution-methanol solution in a volume ratio of 60:40 to prepare a system suitability solution containing impurity C, impurity A, dextroamphetamine and lisdexamfetamine dimethanesulfonate; the solvent is;

[0087] (3) Inject the system suitability solution and the test solution into the liquid chromatograph and record the chromatogram; the chromatographic conditions are as follows: chromatographic column: YMC-Pack ODS-AQ, 4.6×150 mm, 5 μm; mobile phase: sodium octane sulfonate with a pH of 3.5 and a concentration of 0.05 mmol / L as mobile phase A, acetonitrile as mobile phase B, detection wavelength of 205 nm; column temperature of 30°C; injection volume of 20 μL; flow rate: 1.0 mL / min; gradient elution program:

[0088]

[0089] The obtained chromatogram of the test solution was compared with the chromatograms of the solvent blank solution and the excipient blank solution obtained under the same chromatographic conditions, as well as the chromatogram of the system suitability solution, and the peak positions of dextroamphetamine, impurity A, impurity C, and unknown impurities 1-4 in the chromatogram of the test solution were located. Figure 5 From the spectrum, it can be seen that after the content of related substances in the test solution increases, the detection method can still effectively separate the active ingredients, impurity A, impurity C, unknown impurity 1, unknown impurity 2, dextroamphetamine, unknown impurity 3, and unknown impurity 4 of lisdexamfetamine dimesylate capsules.

[0090] Example 5 Detection Method for Related Substances in Lysoxetine Dimesylate Capsules

[0091] (1) The test solution is prepared as follows:

[0092] Take 0.2 g (equivalent to 37.5 mg of lisdexamfetamine dimethanesulfonate) of lisdexamfetamine dimethanesulfonate capsules under high temperature / high humidity conditions (i.e. 40°C / RH75%, placed with packaging for 6 months), place in a 25 mL volumetric flask, add 10 mL of 0.6 mol / L concentrated ammonia methanol solution, shake for 25 minutes, neutralize with 0.6 mol / L formic acid solution, dilute to the scale with 0.1% phosphoric acid solution, shake well, filter, and take the filtrate to obtain the test solution.

[0093] (2) System suitability solution:

[0094] A. Take dextroamphetamine reference substance, impurity A reference substance, and impurity C reference substance respectively, accurately weigh them, dissolve them in 0.1% phosphoric acid solution-methanol with a volume ratio of 60:40, and quantitatively dilute them to prepare an impurity stock solution containing 45 μg of dextroamphetamine, impurity A, and impurity C per 1 mL;

[0095] B. Take 15 mg of lisdexamfetamine dimesylate reference substance, place it in a 10 mL volumetric flask, accurately add 1 mL of stock solution, shake well, and make up to volume with 0.1% phosphoric acid solution-methanol solution in a volume ratio of 60:40 to prepare a system suitability solution containing impurity C, impurity A, dextroamphetamine and lisdexamfetamine dimesylate;

[0096] (3) Inject the system suitability solution and the test solution into the liquid chromatograph and record the obtained spectrum; the chromatographic conditions are as follows: chromatographic column: GL science Inerstil ODS-3, 4.6×150 mm, 5 μm; mobile phase: sodium heptane sulfonate with a pH of 4.0 and a concentration of 0.05 mmol / L as mobile phase A, acetonitrile as mobile phase B, and detection wavelength of 215 nm; column temperature of 35°C; injection volume of 20 μL; flow rate: 1.0 mL / min; gradient elution program:

[0097]

[0098] The obtained chromatogram of the test solution was compared with the chromatograms of the solvent blank solution and the excipient blank solution obtained under the same chromatographic conditions, as well as the chromatogram of the system suitability solution, and the peak positions of dextroamphetamine, impurity A, impurity C, and unknown impurities 1-4 in the chromatogram of the test solution were located. Figure 6From the spectrum, it can be seen that the detection method can effectively separate the active ingredient, impurity A, impurity C, unknown impurity 1, unknown impurity 2, dextroamphetamine, unknown impurity 3, and unknown impurity 4 of lisdexamfetamine dimesylate capsules.

[0099] Example 6 Detection Method for Related Substances in Lysoxetine Dimesylate Capsules

[0100] The only difference from Example 2 is that in the preparation of the test solution: the contents of the lisdexamfetamine dimethanesulfonate capsules are the contents of the lisdexamfetamine dimethanesulfonate capsules that have not been placed under high temperature and high humidity conditions.

[0101] Figure 7 It is the sample solution spectrum of Example 6; As can be seen from the spectrum, the detection method can effectively detect the main component, and no impurity peak appears, indicating that the lysine dimethylate capsules not in a high temperature and high humidity environment are almost free of impurities. This result further proves that the detection method of the present invention can effectively detect the effective ingredients of the lysine dimethylate capsules, and can effectively separate the effective ingredients, known impurities and unknown impurities of the lysine dimethylate capsules.

[0102] Comparative Example 1

[0103] The difference from Example 1 is:

[0104] (1) The test solution is prepared as follows:

[0105] Accurately weigh 0.2 g (equivalent to 37.5 mg) of lisdexamfetamine dimesylate capsules degraded at high temperature (i.e., 40°C / RH75%, placed in packaging for 6 months) and place in a 25 mL volumetric flask. Add 5 mL of 0.3% phosphoric acid solution and 10 mL of methanol. Shake for 10 minutes, dilute to the scale with 0.3% phosphoric acid solution, shake well, filter, and take the filtrate to obtain the test solution.

[0106] (2) Chromatographic conditions: injection volume: 20 μL; flow rate: 1.0 mL / min; column temperature: 30 °C.

[0107] Chromatogram Figure 8 As shown, this method can effectively separate known impurities from unknown impurities, but compared with other embodiments, due to the difference in the extraction method of the test sample, the impurity peak is very small and the impurity detection amount is low.

[0108] Comparative Example 2

[0109] The difference from Example 2 is:

[0110] Sodium octane sulfonate with a pH of 4.5 and a concentration of 0.06 mmol / L was used as mobile phase A, acetonitrile was used as mobile phase B, the detection wavelength was 230 nm, and the column temperature was 55°C.

[0111] Fig. 9 It is the spectrum of the test sample solution of Comparative Example 2; It can be seen from the spectrum that the related substances of the lysine dimethysulfonate amphetamine capsules cannot be detected and separated under this condition, and the method cannot achieve accurate control of the quality of the lysine dimethysulfonate amphetamine capsules.

[0112] Comparative Example 3

[0113] The difference from Example 2 is that the column temperature is 25°C.

[0114] The gradient elution conditions were:

[0115]

[0116]

[0117] Fig.10 This is the spectrum of the test sample solution in Comparative Example 3; as can be seen from the spectrum, this method cannot detect the related substances of lisdexamfetamine dimesylate capsules, and this method is not feasible.

[0118] The unknown impurities 1-4 of the present invention were tested by liquid chromatography-mass spectrometry to determine the molecular ion peak of the unknown impurity 1 [M+H] + is 336.08, molecular weight is 335.08; unknown impurity 2 molecular ion peak [M+H] + is 322.12, molecular weight is 321; unknown impurity 3 molecular ion peak [M+H] + is 292.08, molecular weight is 291.08; unknown impurity 4 molecular ion peak [M+H] + The molecular weight is 292.08 and 291.08.

[0119] The following methodological verification is performed on the detection method of Example 2

[0120] This validation was carried out in accordance with the requirements of the 2020 edition of the Chinese Pharmacopoeia, and the following parameters were verified for the method: system suitability, specificity, accuracy, and limit of quantification. All results met the acceptable standards.

[0121] Dextroamphetamine stock solution: Use dextroamphetamine reference substance as solute to prepare a 1 mg / mL dextroamphetamine solution;

[0122] Impurity A stock solution: Take the impurity A reference substance as the solute and prepare a 1 mg / mL impurity A solution.

[0123] Impurity C stock solution: Use the Impurity C reference substance as the solute to prepare a 1 mg / mL Impurity C solution.

[0124] Impurity mixed stock solution: Accurately measure 1 mL each of dextroamphetamine stock solution, impurity A stock solution, and impurity C stock solution, place in a 25 mL volumetric flask, dilute to the scale with solvent, and shake well.

[0125] Reference substance solution: Use lisdexamfetamine dimesylate reference substance as solute to prepare 3 μg / mL lisdexamfetamine dimesylate solution.

[0126] 1. System applicability

[0127] Lysoxamfetamine dimesylate stock solution: Use lysoxamfetamine dimesylate reference substance as solute to prepare 1 mg / mL lysoxamfetamine dimesylate solution;

[0128] System suitability solution: Weigh 15 mg of lisdexamfetamine dimesylate reference substance into a 10 mL volumetric flask, accurately add 1 mL of impurity mixed stock solution, dilute to the mark with solvent, and shake well.

[0129] Sensitivity solution: Accurately measure 5 mL of the reference solution, place it in a 20 mL volumetric flask, dilute to the mark with solvent, and shake well.

[0130] The solvent used for preparing the above solution: 0.3% phosphoric acid solution-methanol (60:40).

[0131] Determination

[0132] Accurately measure 20 μL of the reference solution and inject it into the liquid chromatograph for 5 times in a row, and record the chromatogram. Accurately measure 20 μL of the sensitivity solution and the system suitability solution, and inject them into the liquid chromatograph to record the chromatogram. The results in Tables 1, 2, and 3 below are obtained from the chromatograms.

[0133] Table 1 Reference solution results

[0134]

[0135] Table 2 Sensitivity solution results

[0136]

[0137] Table 3 System suitability solution results

[0138] Components <![CDATA[Retention time (t R , minutes)]]> Separation Dextroamphetamine 12.501 —— Impurity A 22.467 26.27 Active ingredient peak 26.731 13.89 Impurity C 27.981 4.91

[0139] The reference solution was injected 5 times continuously, and the RSD of the effective ingredient peak area was 0.32% < 2.0%, and the RSD of the retention time was 0.03% < 1.0%. In the system suitability solution chromatogram, the separation between the effective ingredient peak and the impurity C peak was 4.91 > 4.0. In the sensitivity test solution chromatogram, the effective ingredient peak signal-to-noise ratio (S / N) was 136.9 > 10. The system suitability met the acceptable standard.

[0140] 2. Exclusivity

[0141] Solution preparation

[0142] Solvent: 0.3% phosphoric acid solution-methanol (60:40).

[0143] Reagent blank (acid-base neutralization): Take 10 mL of 0.5 mol / L sodium hydroxide methanol solution, neutralize it with 0.5 mol / L hydrochloric acid solution, and dilute it to 25 mL with 0.3% phosphoric acid solution.

[0144] Blank content solution: Accurately weigh 0.175 g of blank content, place in a 25 mL volumetric flask, add 10 mL of 0.5 mol / L sodium hydroxide methanol solution, shake for 10 minutes, neutralize with 0.5 mol / L hydrochloric acid solution, dilute to the scale with 0.3% phosphoric acid solution, shake well, filter, and take the filtrate.

[0145] Test solution: Accurately weigh about 0.2 g (equivalent to 37.5 mg of lisdexamfetamine dimesylate) and place in a 25 mL volumetric flask. Add 10 mL of 0.5 mol / L sodium hydroxide methanol solution and shake for 10 minutes. Neutralize with 0.5 mol / L hydrochloric acid solution and dilute to the scale with 0.3% phosphoric acid solution. Shake well, filter and take the filtrate.

[0146] Dextroamphetamine fixative solution: Accurately measure 1 mL of dextroamphetamine stock solution, place in a 25 mL volumetric flask, dilute to the mark with solvent, and shake well.

[0147] Impurity A positioning solution: Accurately measure 1 mL of impurity A stock solution, place it in a 25 mL volumetric flask, dilute to the scale with solvent, and shake well.

[0148] Impurity C localization solution: Accurately measure 1 mL of the impurity C stock solution, place it in a 25 mL volumetric flask, dilute to the scale with solvent, and shake well.

[0149] Determination

[0150] Take the blank solution (solvent), blank content solution, test solution, reference solution and each known impurity location solution in turn, inject them into the liquid chromatograph, and record the chromatogram.

[0151] The results are shown in Table 4 below.

[0152] Table 4 Interference test and impurity location results

[0153]

[0154] The reagent blank (acid-base neutralization), blank contents, and known impurities do not interfere with the peaks of the active ingredient and impurities, meeting the acceptable standards.

[0155] Take 0.2g of the contents of lisdexamfetamine dimethanesulfonate capsules (equivalent to 37.5mg of lisdexamfetamine dimethanesulfonate) under high temperature / high humidity conditions (i.e. 40°C / RH75%, placed in packaging for 6 months), place in a 25mL volumetric flask, add about 80μg of dextroamphetamine, impurity A, and impurity C, add 10mL of 0.5mol / L sodium hydroxide methanol solution, shake for 30 minutes, neutralize with 0.5mol / L hydrochloric acid solution, dilute to the scale with 0.3% phosphoric acid solution, shake well, filter, take the subsequent filtrate, and obtain the test solution (spiked solution), sample injection determination, the separation of the effective component peak and the adjacent impurities is 3.71 and 5.00. Statistics of each unknown impurity and known impurities, the minimum separation between adjacent impurities is 1.82. The separation between each chromatographic peak can meet the relevant requirements of the pharmacopoeia.

[0156] 3. Accuracy

[0157] Take an appropriate amount of the content of this product and add an appropriate amount of known impurity reference substance to prepare accuracy solutions at four concentration levels, namely 50%, 100%, 150% of the limit concentration and the quantitative limit concentration level. Make three copies for each concentration level and calculate the recovery rate respectively.

[0158] Calculation formula:

[0159] The quantitative limit concentration level results are as follows:

[0160] The recoveries of dextroamphetamine, impurity A, impurity C and active ingredient were 103%-105%, 108%-111%, 95%-98% and 103%-106%, respectively, and the RSD of the recovery results was 0.82%-3.18%.

[0161] The results at 50%, 100%, and 150% concentration levels are as follows:

[0162] The recoveries of dextroamphetamine, impurity A, impurity C, and active ingredient were 103%-105%, 101%-103%, 101%-103%, and 99%-102%, respectively, and the RSD of the recovery results was 0.40%-0.91%. The accuracy verification results met the acceptable standards.

[0163] 4. Limit of Quantitation / Limit of Detection

[0164] Quantitative limit test solution: Take appropriate amount of dextroamphetamine, impurity A, impurity C and lisdexamfetamine dimesylate to prepare a mixed solution with a concentration of about 0.018%, and inject it for determination. The quantitative limit results are as follows:

[0165] The quantitative limits of dextroamphetamine, impurity A, impurity C and active ingredient are 0.018%, 0.017% and 0.018%, respectively, all <0.02%. At this time, the S / N of the chromatographic peaks of dextroamphetamine, impurity A, impurity C and active ingredient are all >10.

[0166] Detection limit investigation solution: Take appropriate amounts of dextroamphetamine, impurity A, impurity C and lisdexamfetamine dimesylate to prepare a mixed solution with a concentration of about 0.002%, and inject the sample for determination. The detection limit results are as follows:

[0167] Table 5 Detection limit results

[0168]

[0169] Detection limit: In the detection limit investigation solution, the S / N of the chromatographic peaks of dextroamphetamine, impurity A, active ingredient, and impurity C were 8.4, 3.3, 6.7, and 9.4, respectively, all >3.

[0170] In the present invention, the principal ingredient of lisdexamfetamine dimesylate capsule is lisdexamfetamine dimesylate, and the above-mentioned effective ingredient is lisdexamfetamine. In the collection of illustrative plates, the principal ingredient marked is lisdexamfetamine.

[0171] In summary, the present invention adopts the mode of high performance liquid chromatography analysis combined with gradient elution to effectively separate known impurities, unknown impurities and capsule effective ingredients, so as to achieve the purpose of effectively controlling the quality of lisdexamfetamine dimethanesulfonate capsules. Meanwhile, the method is simple, efficient, has strong specificity, and has few reference sample types. It is a very convenient method for detecting the related substances of lisdexamfetamine dimethanesulfonate capsules, and has actual application value.

Claims

1. A method for detecting related substances of lisdexamfetamine dimesylate capsules, characterized in that: It is detected by high performance liquid chromatography, and the specific steps are as follows: a. Preparation of test solution: Take the contents of lisdexamfetamine dimesylate capsules, treat with solution, filter, and take the filtrate to obtain; b. Preparation of system suitability solution: Take dextroamphetamine reference substance, impurity A reference substance, and impurity C reference substance, add solvent to dissolve, and obtain impurity stock solution; take lisdexamfetamine dimesylate reference substance, add impurity stock solution and solvent to mix, and obtain; c. Take the test solution and system suitability solution separately and inject them into the chromatograph. The chromatographic conditions are as follows: Chromatographic column: octadecylsilane bonded silica gel as filler; mobile phase: sulfonate solution with pH of 2.0-4.0 as mobile phase A, acetonitrile as mobile phase B; detection wavelength of 200-219nm; gradient elution program: The structural formula of the impurity A is: The structural formula of the impurity C is:

2. The detection method according to claim 1, characterized in that The solution treatment is specifically as follows: adding alkaline alcohol solution to the content to dissolve it, then adding acid solution to neutralize it, adding phosphoric acid solution to shake well and make up to volume.

3. The detection method according to claim 2, characterized in that: The alkaline alcohol solution is one or more of sodium hydroxide methanol solution, sodium hydroxide ethanol solution, potassium hydroxide methanol solution, potassium hydroxide ethanol solution, sodium carbonate methanol solution, sodium bicarbonate methanol solution, sodium phosphate methanol solution, sodium carbonate ethanol solution, sodium bicarbonate ethanol solution, sodium phosphate ethanol solution, concentrated ammonia methanol solution, and concentrated ammonia ethanol solution; the concentration of the alkaline alcohol solution is 0.2-0.8 mol / L.

4. The detection method according to claim 2, characterized in that: The concentration of the phosphoric acid solution is 0.1%-0.5%; the acid solution is one or more of hydrochloric acid solution, sulfuric acid solution, formic acid solution, trifluoroacetic acid solution and phosphoric acid solution; the concentration of the acid solution is 0.2-0.8 mol / L.

5. The detection method according to claim 1, characterized in that: The solvent of step b is phosphoric acid solution-methanol; the volume ratio of the phosphoric acid solution-methanol is 60:40, and the concentration of the phosphoric acid solution is 0.1% to 1%; the concentration of lisdexamfetamine dimesylate in the system suitability solution is 1-5 mg / mL, and the concentrations of dextroamphetamine, impurity A and impurity C are all 1 to 10 μg / mL.

6. The detection method according to claim 1, characterized in that: In step c, the sulfonate is one or more of sodium pentane sulfonate, sodium hexane sulfonate, sodium heptane sulfonate, sodium octane sulfonate, sodium decane sulfonate, and sodium dodecyl sulfonate, preferably sodium octane sulfonate; the concentration of the sulfonate solution is 0.01-0.05 mmol / L, preferably 0.02-0.04 mmol / L.

7. The detection method according to claim 1, characterized in that: The chromatographic conditions include a chromatographic column of Phenomenex Gemini C18, GL science Inertsil ODS-3 or YMC-Pack ODS-AQ, with a specification of 4.6×150 mm, 5 μm; a flow rate of 0.8-1.2 mL / min, a column temperature of 30-50° C., and an injection volume of 20-50 μL.

8. The detection method according to claim 1, characterized in that: The contents of the lisdexamfetamine dimethanesulfonate capsule are the contents of the lisdexamfetamine dimethanesulfonate capsule placed under ≥25°C or the contents of the lisdexamfetamine dimethanesulfonate capsule placed under ≥RH40%; the related impurities detected by the detection method include impurity A, impurity C, dextroamphetamine and unknown impurities 1-4.

9. The detection method according to claim 8, characterized in that: Molecular ion peak of the unknown impurity 1 [M+H] + is 336.08, and the molecular weight is 335.08; Molecular ion peak of the unknown impurity 2 [M+H] + is 322.12, and the molecular weight is 321.12; The molecular ion peak of the unknown impurity 3 [M+H] + is 292.08, and the molecular weight is 291.08; The molecular ion peak of the unknown impurity 4 [M+H] + The molecular weight is 292.08 and 291.

08.

10. The detection method according to claim 8, characterized in that: In the chromatogram of the test solution obtained by the detection method, impurities A, impurity C and dextroamphetamine peak at the corresponding positions of the reference substance; unknown impurity 1, unknown impurity 2, dextroamphetamine, unknown impurity 3, and unknown impurity 4 peak in sequence.

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