Determination method for dissolution curve of calcium gluconate tablets

Abstract

The invention provides a method for determining a dissolution curve of a calcium gluconate tablet, which adopts ion chromatography (IC) chromatography for determination and takes an electrical conductivity detector as a detector. A cation exchange column is used as a chromatographic column; and a methanesulfonic acid solution is used as a leacheate. According to the method, quantification can be carried out through calcium detection, the method has the characteristics of high operability and low interference, and support is provided for evaluation and research on the consistency of the calcium gluconate tablets.

Description

Technical Field

[0001] The present invention relates to the field of chemical drug analysis, and particularly relates to a method for determining the dissolution curve of calcium gluconate tablets. Background Art

[0002] Calcium gluconate tablets are a calcium supplement, which are clinically used for preventing and treating calcium deficiency and supplementing calcium for children, pregnant and lactating women, and the elderly. In the technical requirements for consistency evaluation pharmaceutical research issued by the Center for Drug Evaluation in 2021, it is clearly stated that the dissolution curve of this variety needs to be determined.

[0003] In the quality standard of calcium gluconate tablets included in Part II of the Chinese Pharmacopoeia, only the single-point dissolution rate is measured, and there is no dissolution curve. Whether measuring the dissolution rate or the dissolution curve, it is necessary to first measure the content of the dissolution solution and then calculate further. The method for measuring the dissolution solution in the Chinese Pharmacopoeia is atomic absorption spectrophotometry, which is not applicable to the measurement of the dissolution curve. Because the dissolution curve requires multi-point sampling, if atomic absorption spectrophotometry is used for determination, a large number of dissolution samples need to be diluted, the operation is cumbersome, and the response will be interfered by the matrix of the medium; the method adopted in the content item of the Chinese Pharmacopoeia is complexometric titration, which is also not applicable to the determination of the dissolution curve, and has the disadvantages of large sampling volume, cumbersome operation, and unclear titration endpoint due to low sample concentration.

[0004] Chinese Patent CN 110487949 A discloses a method for detecting the dissolution curve of calcium gluconate tablets, using high performance liquid chromatography (HPLC). Chromatographic column: a chromatographic column filled with octadecylsilyl silica gel. Mobile phase: 0.02 mol / L potassium dihydrogen phosphate solution (adjusting pH). Detection wavelength: 210 nm. The continuous dissolution filtrate can be directly injected for analysis, improving the operation simplicity. However, the method disclosed in this patent can only detect the acid radical of the non-active ingredient of the drug, but cannot detect the active ingredient calcium.

[0005] In the existing methods for determining the dissolution curve of calcium gluconate, the atomic spectrophotometry and complexometric titration in the pharmacopoeia can detect the active ingredient calcium of the drug, but have the disadvantages of cumbersome operation, matrix interference or unclear titration endpoint, and are not applicable to the multi-point determination of the dissolution curve; high performance liquid chromatography (HPLC) can only detect the acid radical of the non-active ingredient of the drug through end absorption, but cannot detect the active ingredient calcium. Summary of the Invention

[0006] To solve the above problems, the present invention uses ion chromatography to determine the dissolution curve of calcium gluconate tablets. It can not only perform quantitative analysis through the detection of calcium, but also has the characteristics of strong operability and few interferences, providing support for the consistency evaluation research of calcium gluconate tablets. To achieve the above object, the present invention provides a method for determining the dissolution curve of calcium gluconate tablets, which is determined by ion chromatography (IC) using a conductivity detector, a cation exchange column as the chromatographic column, and methanesulfonic acid solution as the eluent.

[0007] Preferably, the chromatographic column is a Dionex IonPac CS12A cation exchange column.

[0008] Preferably, the eluent is a 18 - 22 mmol / L methanesulfonic acid solution, and more preferably, the eluent is a 20 mmol / L methanesulfonic acid solution.

[0009] Preferably, the column temperature of the chromatographic column is 25°C - 35°C, and more preferably, the column temperature of the chromatographic column is 30°C.

[0010] Preferably, the flow rate of the eluent is 0.9 - 1.1 ml / min, and more preferably, the flow rate is 1.0 ml / min.

[0011] A method for determining the dissolution curve of calcium gluconate tablets, characterized by comprising the following steps:

[0012] (1) Preparation of reference solution: Weigh an appropriate amount of calcium gluconate reference substance accurately, dissolve it in water and quantitatively dilute it to prepare solutions containing approximately 0.1 mg, 0.4 mg, and 0.7 mg per 1 mL respectively.

[0013] (2) Preparation of test solution: Filter the dissolution solution and take the subsequent filtrate as the test solution.

[0014] (3) Set chromatographic conditions: Dionex IonPac CS12A cation exchange column; using 20 mmol / L methanesulfonic acid solution as the eluent; flow rate 1.0 mL / min, conductivity detector, column temperature 30°C.

[0015] (4) Determination method and result calculation: Accurately measure 10 μl of each of the above reference solution and test solution, inject them into the ion chromatograph, and record the chromatogram. Plot the peak area against the concentration for the reference solution and perform linear regression, with the correlation coefficient R2 not less than 0.998. Calculate the dissolution amount using the linear regression equation and plot the dissolution curve.

[0016] The present invention also provides a method for determining the dissolution curve of calcium gluconate tablets for bulk drugs and related preparations of calcium gluconate tablets.

[0017] The method for determining the dissolution curve of the calcium gluconate tablets of the present invention has the following advantages compared with the prior art:

[0018] The present invention uses ion chromatography to determine the dissolution curve of calcium gluconate tablets, which can not only perform quantification through the detection of calcium, but also has the characteristics of strong operability and few interferences, providing support for the consistency evaluation research of calcium gluconate tablets. And a detailed methodology investigation has been carried out on its determination method. Through specificity, linearity and range test, recovery test, repeatability test, precision test, solution stability test and durability test research, it shows that it is feasible to use this method to determine the dissolution curve of calcium gluconate tablets, which can perform quantification by detecting the active ingredient calcium in the drug, and has strong operability, good specificity and high accuracy. Description of the Drawings

[0019] Figure 1 : Diagram of the determination results of the dissolution curve of calcium gluconate tablets

[0020] Figure 2 : Chromatogram of the specificity test

[0021] Figure 3 : Diagram of the results of the linearity and range test Detailed Embodiments

[0022] To make the objectives, technical solutions and effects of the present invention clearer and more definite, the following further describes the present invention in detail with reference to the accompanying drawings and by way of examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0023] Example 1: Determination of the dissolution curve of calcium gluconate

[0024] 1. Instruments and reagents:

[0025] Ion chromatograph (Thermo Fisher, model ICS600), electronic analytical balance (Mettler Toledo, model XPE205), dissolution tester (TianDa TianFa, model RC806D), calcium gluconate tablets (self-made, specification 500 mg, batch number: 240802), calcium gluconate reference substance (National Institutes for Food and Drug Control, content 100%).

[0026] 2. Chromatographic conditions:

[0027] Chromatographic column: Dionex IonPac CS12A cation exchange column (4×250 mm); eluent: 20 mmol / L methanesulfonic acid aqueous solution; flow rate: 1.0 mL / min; detector: conductivity detector, column temperature: 30°C.

[0028] 3. Preparation of solutions:

[0029] (1) Preparation of reference solution: Accurately weigh 55 mg of calcium gluconate reference substance, place it in a 25-mL volumetric flask, dissolve it with water and dilute to the mark, shake well to prepare the reference stock solution. Accurately pipette 0.5 mL, 1 mL, and 3 mL of the above reference stock solution respectively into 10-mL volumetric flasks, dilute to the mark with water, and shake well to obtain the reference solutions.

[0030] (2) Preparation of test solution: Take 6 tablets of calcium gluconate tablets (batch number: 240802), use 900 mL of water as the dissolution medium, paddle method, rotation speed of 50 revolutions per minute. Sampling is carried out at 5 min, 10 min, 15 min, 30 min, 45 min, and 60 min, filter, and take the subsequent filtrate as the test solution.

[0031] 4. Determination method: Accurately pipette 10 μL of the test solution and the reference solution respectively, inject them into the ion chromatograph, and record the chromatogram. Calculate the dissolution amount using the linear regression equation and plot the dissolution curve. The results of the dissolution curve determination are shown in Figure 1 .

[0032] 5. Results and conclusions: The within-batch uniformity of the self-made calcium gluconate tablets is good.

[0033] Example 2: Specificity verification

[0034] 1. Preparation of solutions:

[0035] Preparation of blank solvent: Take an appropriate amount of water to obtain it.

[0036] Preparation of blank excipient solution: Accurately weigh 108 mg of blank excipients, place them in a 100-mL volumetric flask, add an appropriate amount of water, sonicate for 10 min, let it cool, dilute to the mark with water, and shake well to obtain the blank excipient stock solution. Accurately pipette 0.5 mL of the blank excipient stock solution into a 10-mL volumetric flask, dilute to the mark with water, shake well, and filter to obtain the blank excipient solution.

[0037] Preparation of reference solution: Accurately weigh 222.65 mg of calcium gluconate reference substance, place it in a 100-mL volumetric flask, dilute to the mark with the dissolution medium, and shake well to obtain the reference stock solution. Accurately pipette 0.5 mL of the above reference stock solution into a 10-mL volumetric flask, dilute to the mark with water, and shake well to obtain it.

[0038] 2. Chromatographic conditions:

[0039] Chromatographic column: Dionex IonPac CS12A cation exchange column (4×250 mm); eluent: 20 mmol / L aqueous solution of methanesulfonic acid; flow rate: 1.0 mL / min; detector: conductivity detector, column temperature: 30 °C.

[0040] 3. Determination method: According to the determined chromatographic conditions, accurately measure 10 μl of blank solvent, reference solution, blank excipient solution, and test solution respectively, inject them into the ion chromatograph, and record the chromatogram.

[0041] 4. Results and conclusions: The blank solvent and the blank excipient solution showed no interference at the main peak position of the reference solution, indicating good method specificity. The results are shown in Figure 2 .

[0042] Example 3: Verification of linearity and range

[0043] 1. Preparation of solutions:

[0044] Preparation of linear solutions: Accurately measure 0.5, 1.3, 2.0, 2.5, and 3.0 mL of the reference stock solution under "specificity" respectively, transfer them into 10 mL volumetric flasks, dilute to the mark with water, and shake well to obtain linear solutions 1 - 5 with calcium gluconate concentrations of 0.1113 mg / mL, 0.2894 mg / mL, 0.4453 mg / mL, 0.5566 mg / mL, and 0.6680 mg / mL respectively.

[0045] 2. Chromatographic conditions:

[0046] Chromatographic column: Dionex IonPac CS12A cation exchange column (4×250 mm); Eluent: 20 mmol / L aqueous solution of methanesulfonic acid; Flow rate: 1.0 mL / min; Detector: Conductivity detector, Column temperature: 30 °C.

[0047] 3. Determination method: According to the determined chromatographic conditions, accurately measure linear solutions 1 - 5 respectively, inject them into the ion chromatograph, and record the chromatogram. Plot the peak area against the concentration and perform linear regression.

[0048] 4. Results and conclusions: In the concentration range of 0.1113 mg / mL - 0.6680 mg / mL, there was a good linear relationship between the calcium gluconate concentration and the peak area. The linear regression equation was y = 11.884x - 0.2664, and the correlation coefficient R2 = 0.999. The results are shown in Figure 3 . Example 4: Verification of recovery

[0049] 1. Preparation of solutions:

[0050] Preparation of reference solutions: Accurately measure 0.5, 2.0, and 3.0 ml of the linear stock solution under "specificity" respectively, transfer them into 10 ml volumetric flasks, dilute to the mark with the dissolution medium, and shake well.

[0051] Preparation of test solution: Accurately measure 0.5 ml of the blank excipient stock solution under "Specificity", transfer it to a 10-ml volumetric flask, and then accurately add 0.5 ml, 2.0 ml, and 3.0 ml of the reference substance stock solution under "Specificity" respectively. Dilute to the mark with water, shake well, filter, and take the subsequent filtrate to obtain spiked solutions with dissolution concentration levels of 20%, 80%, and 120%. Prepare 3 replicates for each concentration, with a total of 9 replicates prepared.

[0052] 2. Chromatographic conditions:

[0053] Chromatographic column: Dionex IonPac CS12A cation exchange column (4×250 mm); Eluent: 20 mmol / L aqueous solution of methanesulfonic acid; Flow rate: 1.0 mL / min; Detector: Conductivity detector, Column temperature: 30 °C.

[0054] 3. Determination method: According to the determined chromatographic conditions, accurately measure 10 μl of the reference substance solution and the test solution respectively, inject them into the ion chromatograph, record the chromatogram, and calculate the recovery rate using the linear regression equation.

[0055] 4. Results and conclusions: For calcium gluconate within the dissolution concentration range of 20% - 120%, the recovery rates were between 98% and 102%. The average recovery rate of 9 samples was 100.3%, and the RSD was 1.15%. The recovery rate of the method was good. The results are shown in Table 1.

[0056] Table 1 Results of the recovery test

[0057]

[0058] Example 5: Verification of injection precision

[0059] 1. Preparation of solution:

[0060] Preparation of test solution: Accurately weigh 11.23 mg, 44.44 mg, and 66.68 mg of calcium gluconate raw material respectively, transfer them to a 100-ml volumetric flask, dilute to the mark with water, and shake well to obtain solutions with dissolution concentration levels of 20%, 80%, and 120%.

[0061] 2. Chromatographic conditions:

[0062] Chromatographic column: Dionex IonPac CS12A cation exchange column (4×250 mm); Eluent: 20 mmol / L aqueous solution of methanesulfonic acid; Flow rate: 1.0 mL / min; Detector: Conductivity detector, Column temperature: 30 °C.

[0063] 3. Determination method: According to the determined chromatographic conditions, accurately measure the test solution, inject it into the chromatograph, and record the chromatogram. Inject the sample continuously 6 times for each concentration, and record the peak areas.

[0064] 4. Results and Conclusions: The RSDs of the peak areas of the solutions at the concentration levels of 20% - 120% were 0.31%, 0.28%, and 0.60%, all not greater than 2%, indicating good injection precision of the method. The results are shown in Table 2.

[0065] Table 2 Results of the Injection Precision Test

[0066]

[0067]

[0068] Example 6: Repeatability Verification

[0069] 1. Preparation of Solutions:

[0070] Preparation of the reference solution: Accurately pipette 0.5, 2.0, and 3.0 ml of the linear stock solution under "Specificity" into a 10-ml volumetric flask, dilute to the mark with the dissolution medium, and shake well.

[0071] Preparation of the test solution: Take 1 tablet of this product for dissolution test, sample from the dissolution cup at 5 min and 60 min, filter, and take the subsequent filtrate as the test solution. Prepare 6 samples by parallel filtration at each sampling time point.

[0072] 2. Chromatographic Conditions:

[0073] Chromatographic column: Dionex IonPac CS12A cation exchange column (4 × 250 mm); Eluent: 20 mmol / L aqueous solution of methanesulfonic acid; Flow rate: 1.0 mL / min; Detector: Conductivity detector, Column temperature: 30 °C.

[0074] 3. Determination Method: According to the determined chromatographic conditions, accurately pipette 10 μl of the reference solution and the test solution respectively, inject them into the ion chromatograph, record the chromatogram, and calculate the dissolution amount using the linear regression equation.

[0075] 4. Results and Conclusions: The RSDs of the 6 samples were 0.82% and 0.16% respectively, both less than 2%, indicating good repeatability of the method. The results are shown in Table 3.

[0076] Table 3 Results of the Repeatability Test

[0077]

[0078]

[0079] Example 7: Solution Stability Verification

[0080] 1. Preparation of Solutions:

[0081] Preparation of test solution: Accurately weigh 22.22 mg and 55.62 mg of calcium gluconate bulk drug respectively, place them in a 100 ml volumetric flask, dilute to the mark with water, shake well to obtain solutions with dissolution concentration levels of 40% and 100%, and store at room temperature.

[0082] 2. Chromatographic conditions:

[0083] Chromatographic column: Dionex IonPac CS12A cation exchange column (4×250 mm); Eluent: 20 mmol / L aqueous solution of methanesulfonic acid; Flow rate: 1.0 mL / min; Detector: Conductivity detector, Column temperature: 30 °C.

[0084] 3. Determination method: According to the determined chromatographic conditions, accurately measure the test solution, and inject it into the chromatograph at 0 h, 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, and 10 h respectively, and record the peak area.

[0085] 4. Results and conclusions: The RSD of the 40% solution is 0.82%, and the RSD of the 100% solution is 0.36%, indicating that the solution can remain stable within 10 h at room temperature. The results are shown in Table 4.

[0086] Table 4 Results of solution stability test

[0087]

[0088]

[0089] Example 8: Durability verification

[0090] 1. Preparation of solution:

[0091] Preparation of reference solution: Accurately measure 2.5, 10, and 15 ml of the reference stock solution under "specificity" respectively, place them in a 50 ml volumetric flask, dilute to the mark with water, and shake well.

[0092] Preparation of test solution: Take 1 tablet of this product for dissolution test, sample from the dissolution cup at 5 min and 60 min, filter, and take the subsequent filtrate.

[0093] 2. Chromatographic conditions:

[0094] Chromatographic column: Dionex IonPac CS12A cation exchange column (4×250 mm); Eluent: 20 mmol / L aqueous solution of methanesulfonic acid; Flow rate: 1.0 mL / min; Detector: Conductivity detector, Column temperature: 30 °C.

[0095] 3. Determination method: According to the determined chromatographic conditions and the chromatographic conditions with slight changes, accurately measure 10 μl of the reference solution and the test solution, inject them into the ion chromatograph respectively, record the chromatogram, and calculate the dissolution amount using the linear regression equation.

[0096] 4. Results and conclusions: When the concentration of methanesulfonic acid changes by ±10% and the eluent flow rate changes by ±10%, the RSDs of the dissolution amount are 1.05% and 0.75% respectively, both less than 2.0%. The slight changes in the chromatographic conditions have no obvious influence on the determination, and the durability of the method is good. The results are shown in Table 5.

[0097] Table 5 Results of the durability test

[0098]

[0099]

Claims

1. A method for determining the dissolution curve of calcium gluconate tablets, characterized in that: The determination was carried out by ion chromatography (IC) chromatography, and the determination conditions of the ion chromatography were: a conductivity detector was used as a detector; a cation exchange column was used as a chromatographic column; and a methanesulfonic acid solution was used as an eluent.

2. The measuring method according to claim 1, characterized in that The chromatographic column is a Dionex IonPac CS12A cation exchange column.

3. The measuring method according to claim 1, characterized in that The eluent is a 18-22 mmol / L methanesulfonic acid solution.

4. The measuring method according to claim 3, characterized in that The eluent is a 20 mmol / L methanesulfonic acid solution.

5. The measuring method according to claim 1, characterized in that The flow rate of the eluent is 0.9-1.1 mL / min.

6. The measuring method according to claim 5, characterized in that The flow rate of the eluent is 1.0 ml / min.

7. The measuring method according to claim 1, characterized in that The column temperature of the chromatographic column is 25°C to 35°C.

8. The measuring method according to claim 7, characterized in that The column temperature of the chromatographic column is 30°C.

9. A method for determining the dissolution curve of calcium gluconate tablets, characterized in that: The following steps are involved: (1) Preparation of reference solution: Take an appropriate amount of calcium gluconate reference substance, weigh accurately, dissolve in water and quantitatively dilute to make solutions containing approximately 0.1 mg, 0.4 mg, and 0.7 mg per 1 mL. (2) Preparation of test solution: Filter the eluate and take the filtrate as the test solution. (3) Setting the chromatographic conditions: Dionex IonPac CS12A cation exchange column; 20 mmol / L methanesulfonic acid solution as eluent; flow rate 1.0 mL / min, conductivity detector, column temperature 30°C. (4) Determination method and result calculation: Accurately measure 10 μl of the above-mentioned reference solution and test solution, inject them into the ion chromatograph, and record the chromatogram. The reference solution is plotted as peak area versus concentration, and linear regression is performed. The correlation coefficient R 2 Not less than 0.

998. Use linear regression equation to calculate dissolution amount and draw dissolution curve.

10. The method for determining the dissolution curve of calcium gluconate tablets according to any one of claims 1 to 9, characterized in that: The method is used for determining the dissolution curve of calcium gluconate tablets raw materials and calcium gluconate tablets related preparations.

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