Analysis method for determining main drug content of lansoprazole sodium bicarbonate capsule

Abstract

The invention belongs to the technical field of chemical analysis, and discloses an analysis method for determining the content of a main drug of a lansoprazole sodium bicarbonate capsule, and the main scheme is as follows: a methanol-water-triethylamine mixed solution is taken as a diluent, and after dissolution, an ultraviolet spectrophotometry (UV) is directly adopted for determination at the wavelength of 264 nm by an external standard method. According to experiments, methanol and water in the diluent can effectively dissolve the substance, triethylamine as alkali can effectively protect degradation of lansoprazole in the dissolving process, and compared with a determination method for the content of the product in the 2020 edition of Chinese Pharmacopoeia, the determination analysis method has the advantages of high efficiency, convenience, economy and the like.

Description

Technical Field

[0001] The invention relates to the technical field of chemical analysis, in particular to an analytical method for determining the content of a main drug of lansoprazole sodium bicarbonate capsules. Background Art

[0002] Currently, the 2020 edition of the Pharmacopoeia uses high-performance liquid chromatography (HPLC) to determine the content of the main drug of lansoprazole sodium bicarbonate capsules. It uses methanol-water-triethylamine-phosphoric acid (600:400:5:1.5) [the pH value is adjusted to 7.3 with phosphoric acid solution (1→10)] as the mobile phase. When this method is used for compound preparations, lansoprazole is slowly degraded during the dissolution process, and the content value cannot be accurately measured. Summary of the invention

[0003] The purpose of the present invention is to provide an analytical method for determining the content of the main drug of lansoprazole sodium bicarbonate capsules in view of the above technical defects existing in the existing high performance liquid chromatography (HPLC) method for determining the content of the main drug of lansoprazole sodium bicarbonate capsules, which has the advantages of high efficiency, convenience, economy and the like.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] The invention discloses an analytical method for determining the content of a main drug of lansoprazole sodium bicarbonate capsules. The method uses a mixed solution of methanol-water-triethylamine as a diluent, and directly adopts ultraviolet spectrophotometry (UV) at a wavelength of 264 nm to determine the content of the main drug by an external standard method after dissolution.

[0006] Preferably, the mass ratio of methanol, water and triethylamine in the methanol-water-triethylamine mixture is 50-70:30-50:0.8-1.2.

[0007] Preferably, the mass ratio of methanol, water and triethylamine in the methanol-water-triethylamine mixture is 60:40:1.

[0008] Preferably, the analytical method for determining the content of the main drug of lansoprazole sodium bicarbonate capsules comprises the following determination steps:

[0009] (1) Preparation of test solution: Lansoprazole sodium bicarbonate capsules, approximately equivalent to 20 mg of lansoprazole sodium bicarbonate, accurately weighed, placed in a 100 ml volumetric flask, diluted to the mark with methanol-water-triethylamine (60:40:1), shaken well, and used as the control solution (0.2 mg / ml);

[0010] (2) Preparation of control solution: Take about 20 mg of lansoprazole sodium bicarbonate capsule reference substance, accurately weigh it, put it in a 100 ml volumetric flask, dilute it to the mark with methanol-water-triethylamine (60:40:1), shake well, and use it as the control solution (0.2 mg / ml);

[0011] (3) Take the above test solution and reference solution, measure the absorbance A value at 264 nm by ultraviolet spectrophotometry, and calculate the content by external standard method.

[0012] The present invention adopts the above technical solution, which has the following technical effects compared with the prior art:

[0013] The method of the present invention uses ultraviolet spectrophotometry (UV), with methanol-water-triethylamine (60:40:1) as the diluent, and direct ultraviolet reading after dissolution is economical, efficient, fast and accurate; experimentally found that methanol and water in the diluent can effectively dissolve the substance, and triethylamine as a base can effectively protect the degradation of lansoprazole during the dissolution process; the determination and analysis method of the present invention is compared with the determination method for the content of this product in the 2020 edition of the Chinese Pharmacopoeia, and this method has the advantages of high efficiency, convenience and economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a linear graph of the content of the main drug lansoprazole in the verification test of the method of the present invention. DETAILED DESCRIPTION

[0015] The present invention is described in detail and specifically by specific examples below to provide a better understanding of the present invention, but the following examples do not limit the scope of the present invention.

[0016] Example

[0017] An analytical method for determining the content of the main drug of lansoprazole sodium bicarbonate capsules, using a mixture of methanol-water-triethylamine as a diluent, dissolving and directly using ultraviolet spectrophotometry (UV) at a wavelength of 264nm to determine by an external standard method. The mass ratio of methanol, water and triethylamine in the mixture of methanol-water-triethylamine is 50-70:30-50:0.8-1.2, preferably, the mass ratio of methanol, water and triethylamine in the mixture of methanol-water-triethylamine is 60:40:1.

[0018] Specifically, the analytical method for determining the content of the main drug of lansoprazole sodium bicarbonate capsules comprises the following determination steps:

[0019] (1) Preparation of test solution: Lansoprazole sodium bicarbonate capsules, approximately equivalent to 20 mg of lansoprazole sodium bicarbonate, accurately weighed, placed in a 100 ml volumetric flask, diluted to the mark with methanol-water-triethylamine (60:40:1), shaken well, and used as the control solution (0.2 mg / ml);

[0020] (2) Preparation of control solution: Take about 20 mg of lansoprazole sodium bicarbonate capsule reference substance, accurately weigh it, put it in a 100 ml volumetric flask, dilute it to the mark with methanol-water-triethylamine (60:40:1), shake well, and use it as the control solution (0.2 mg / ml);

[0021] (3) Take the above test solution and reference solution, measure the absorbance A value at 264 nm by ultraviolet spectrophotometry, and calculate the content by external standard method.

[0022] 1. Method validation:

[0023] 1.1 Test solution: 20 capsules of this product, take the content equivalent to 20 mg of lansoprazole sodium bicarbonate, accurately weigh, place in a 100 ml volumetric flask, dilute to the mark with methanol-water-triethylamine (60:40:1), shake well, and use as the control solution (0.2 mg / ml). (Prepare 2 portions in parallel)

[0024] Reference solution: Take about 20 mg of lansoprazole reference substance, accurately weigh it, put it in a 100 ml volumetric flask, dilute it to the scale with methanol-water-triethylamine (60:40:1), shake well, and use it as the reference solution (0.2 mg / ml).

[0025] (Prepare 2 copies in parallel)

[0026] Determination method: Take the reference solution and the test solution, measure the absorbance at a wavelength of 264nm according to the UV-visible spectrophotometry (General Rules 0401 of Part IV of the Chinese Pharmacopoeia 2020 Edition), and calculate according to the external standard method to obtain the result.

[0027] 1.2 Sampling requirements and acceptance criteria

[0028]

[0029] 1.3 Calculation method and result determination

[0030] Calculation formula:

[0031]

[0032] Where: A 样 -Absorbance of the test solution;

[0033] A 对 -Absorbance of the reference solution;

[0034] W 对 -weight of the reference substance, g;

[0035] P 对 -Purity of reference substance, %.

[0036] Specifications, 20mg (0.02g)

[0037] Limit: Calculated by absorbance using the external standard method, the lansoprazole content should be 90.0% to 110.0% of the labeled amount.

[0038] 2. Exclusive test

[0039] 2.1 Specific operations

[0040] Blank solution: methanol-water-triethylamine (60:40:1) as diluent auxiliary solution:

[0041] Excipient solution: Take an appropriate amount of all the excipients, weigh accurately, place in a 100ml volumetric flask, dilute to the mark with methanol-water-triethylamine (60:40:1), and shake well.

[0042] Capsule shell solution: Take 10 empty capsule shells, place them in a 100 ml volumetric flask, dilute to the mark with methanol-water-triethylamine (60:40:1), and shake well.

[0043] Test solution: 20 capsules of this product, take the content approximately equivalent to 20 mg of lansoprazole sodium bicarbonate, accurately weigh, place in a 100 ml volumetric flask, use methanol-water-triethylamine (60:40:1) as diluent to the scale, shake well, as the control solution (0.2 mg / ml) Reference solution: Take about 20 mg of lansoprazole reference substance, accurately weigh, place in a 100 ml volumetric flask, use methanol-water-triethylamine (60:40:1) as diluent to the scale, shake well, as the control solution (0.2 mg / ml).

[0044] Determination method: Take the reference solution and the test solution, measure the absorbance at a wavelength of 264nm according to the UV-visible spectrophotometry (General Rules 0401 of Part IV of the Chinese Pharmacopoeia 2020 Edition), and calculate according to the external standard method to obtain the result.

[0045] 2.2 Sampling requirements and acceptance criteria

[0046]

[0047] 2.3 Results and Conclusions

[0048] Table 1 Specificity test results

[0049]

[0050]

[0051] Conclusion: The blank solvent interferes with the main peak determination, and the interference amount of blank excipients and capsule shell solution is 0.000%, less than 2.0%, which meets the requirements and has good specificity.

[0052] 3. Linearity test

[0053] 3.1 Specific operation (avoid light)

[0054] Linear stock solution: Take about 40 mg of the reference substance, accurately weigh it, put it in a 20 ml volumetric flask, dilute it to the scale with methanol-water-triethylamine (60:40:1), shake well, and use it as the linear stock solution.

[0055] Linear solution: Accurately measure 0.8ml, 1.6ml, 2ml, 2.4ml and 2.8ml of the linear stock solution and place them in different 100ml volumetric flasks respectively. Dilute to the scale with methanol-water-triethylamine (60:40:1) as the diluent and shake well. Use them as linear solutions with limits of 40%, 80%, 100%, 120% and 140% respectively.

[0056] Take the linear solutions of each limit and measure the absorbance at a wavelength of 264 nm according to the UV-visible spectrophotometry (General Rules of Part IV of the Chinese Pharmacopoeia 2020 Edition 0401).

[0057] 3.2 Sampling requirements and acceptance criteria

[0058]

[0059] 3.3 Results and Conclusions

[0060] Table 2 Linearity test results

[0061]

[0062]

[0063] Conclusion: Within the concentration range of 0.0017 to 0.0058 mg / ml (equivalent to the limit range of 40% to 140%), Figure 1 As shown, the concentration of isotretinoin has a good linear relationship with the peak area, the linear equation is y=135.7356x+0.0019, the linear correlation coefficient is 0.99906, which is greater than 0.998, and the ratio of the absolute value of the Y-axis intercept to the 100% theoretical concentration response value is 0.35%, which is less than 2.0%, which meets the requirements and has a good linear relationship.

[0064] The specific embodiments of the present invention are described in detail above, but they are only examples, and the present invention is not limited to the specific embodiments described above. For those skilled in the art, any equivalent modifications and substitutions made to the present invention are also within the scope of the present invention. Therefore, the equalization changes and modifications made without departing from the spirit and scope of the present invention should be included in the scope of the present invention.

Claims

1. An analytical method for determining the content of the main drug of lansoprazole sodium bicarbonate capsules, characterized in that: A mixture of methanol-water-triethylamine was used as a diluent, and after dissolution, ultraviolet spectrophotometry (UV) was used to directly determine the external standard method at a wavelength of 264 nm.

2. The analytical method for determining the content of the main drug of lansoprazole sodium bicarbonate capsules according to claim 1, characterized in that: The mass ratio of methanol, water and triethylamine in the methanol-water-triethylamine mixed solution is 50-70:30-50:0.8-1.

2.

3. The analytical method for determining the content of the main drug of lansoprazole sodium bicarbonate capsules according to claim 1, characterized in that: The mass ratio of methanol, water and triethylamine in the methanol-water-triethylamine mixture is 60:40:

1.

4. The analytical method for determining the content of the main drug of lansoprazole sodium bicarbonate capsules according to claim 1, characterized in that: The measurement steps include the following: (1) Preparation of test solution: Lansoprazole sodium bicarbonate capsules, approximately equivalent to 20 mg of lansoprazole sodium bicarbonate, accurately weighed, placed in a 100 ml volumetric flask, diluted to the mark with methanol-water-triethylamine (60:40:1), shaken well, and used as the control solution (0.2 mg / ml); (2) Preparation of control solution: Take about 20 mg of lansoprazole sodium bicarbonate capsule reference substance, accurately weigh it, put it in a 100 ml volumetric flask, dilute it to the mark with methanol-water-triethylamine (60:40:1), shake well, and use it as the control solution (0.2 mg / ml); (3) Take the above test solution and reference solution, measure the absorbance A value at 264 nm by ultraviolet spectrophotometry, and calculate the content by external standard method.

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