A method for determining the dissolution curve of calcium gluconate tablets

Abstract

The application provides a method for determining the dissolution curve of calcium gluconate tablets, which is determined by ion chromatography (IC) and uses a conductance detector as a detector, a cation exchange column as a chromatographic column and a methyl sulfonic acid solution as a eluent. The method can quantitatively determine calcium and has the characteristics of strong operability and less interference, and provides support for the consistency evaluation research of the calcium gluconate tablets.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of chemical drug analysis, in particular to a method for determining the dissolution curve of calcium gluconate tablets. BACKGROUND

[0002] Calcium gluconate tablets are a calcium supplement used in the clinic to prevent and treat calcium deficiency and calcium supplementation for children, pregnant and lactating women, and the elderly. In the Consistency Evaluation Pharmaceutical Research Technical Requirements published by the Drug Review Center in 2021, it is clearly stated that the dissolution curve of this product needs to be determined.

[0003] The quality standard for calcium gluconate tablets in the second part of the Chinese Pharmacopoeia only measures the dissolution at a single point, without a dissolution curve. Whether it is to measure the dissolution or the dissolution curve, it is necessary to first measure the content of the dissolution liquid and then further calculate it. The measurement method of the dissolution liquid in the Chinese Pharmacopoeia is atomic absorption spectrophotometry, which is not suitable for the measurement of the dissolution curve, because the dissolution curve requires multiple sampling. If atomic absorption spectrophotometry is used for determination, a large number of dissolution samples need to be diluted, which is cumbersome to operate and the response will be disturbed by the medium matrix. The method used in the content item of the Chinese Pharmacopoeia is complexometric titration, which is also not suitable for the determination of the dissolution curve, with the disadvantages of large sampling volume, cumbersome operation, and low sample concentration leading to unclear titration end point.

[0004] Chinese patent CN 110487949 A discloses a method for detecting the dissolution curve of calcium gluconate tablets, using high performance liquid chromatography (HPLC), a chromatographic column: a chromatographic column with octadecyl-bonded silica gel as the filler, mobile phase: 0.02 mol / L potassium dihydrogen phosphate solution (pH adjusted), detection wavelength: 210 nm, the dissolution filtrate can be directly sampled for analysis, the operation is simple, but the method disclosed in this patent can only detect the non-active ingredient of the drug, the acid radical, and 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 methods of the pharmacopoeia can detect the active ingredient of the drug, calcium, but have the disadvantages of cumbersome operation, matrix interference or unclear titration end point, and are not suitable for the determination of the dissolution curve at multiple points. High performance liquid chromatography (HPLC) can only detect the non-active ingredient of the drug, the acid radical, through end absorption, and cannot detect the active ingredient, calcium. SUMMARY

[0006] In order to solve the above problems, the present application adopts ion chromatography to determine the dissolution curve of calcium gluconate tablets, which can be quantified by detecting calcium, has strong operability and less interference, and provides support for the consistency evaluation of calcium gluconate tablets.

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

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

[0009] Preferably, the column temperature of the chromatographic column is 25-35℃, and further preferably, the column temperature of the chromatographic column is 30℃.

[0010] Preferably, the flow rate of the eluent is 0.9-1.1 ml / min, and further 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: accurately weigh a certain amount of calcium gluconate reference substance, dissolve and quantitatively dilute with water to prepare a solution containing about 0.1 mg, 0.4 mg and 0.7 mg per 1 mL.

[0013] (2) Preparation of test solution: filter the dissolution liquid, and take the filtrate as the test solution.

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

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

[0016] The present application also provides a method for determining the dissolution curve of calcium gluconate tablet raw material and related preparations.

[0017] The method for measuring the dissolution curve of the calcium gluconate tablet has the following advantages compared with the prior art:

[0018] The method for measuring the dissolution curve of the calcium gluconate tablet has the following advantages compared with the prior art: BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 Figure 1 is a dissolution curve measurement result diagram of the calcium gluconate tablet.

[0020] Figure 2 Figure 4 is a chromatogram of the specificity test.

[0021] Figure 3 Figure 5 is a linear and range test result diagram. DETAILED DESCRIPTION

[0022] To make the purpose, technical scheme and effect of the present application more clear and definite, the present application is further described in detail below with reference to the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and do not limit the present application.

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

[0024] 1. Instruments and reagents:

[0025] Ion chromatograph (Thermo, model ICS600), electronic analytical balance (Mettler Toledo, model XPE205), dissolution tester (Tianda Tianfa, model RC806D), calcium gluconate tablets (self-made, specification 500mg, batch number: 240802), calcium gluconate reference substance (China Institute for Drug Control, content 100%).

[0026] 2. Chromatographic conditions:

[0027] Chromatographic column: Dionex IonPac CS12A cation exchange column (4x250mm); eluent: 20mmol / L methanesulfonic acid aqueous solution; flow rate: 1.0mL / min; detector: conductivity detector, column temperature: 30℃.

[0028] 3. Preparation of solutions:

[0029] (1) Preparation of reference solution: Weigh 55 mg of calcium gluconate reference standard accurately, place it in a 25 mL volumetric flask, dissolve and dilute to the mark with water, shake well to prepare reference stock solution. Accurately measure 0.5 mL, 1 mL and 3 mL of the above reference stock solution respectively, place them in a 10 mL volumetric flask, dilute to the mark with water, shake well to prepare reference solutions.

[0030] (2) Preparation of test solution: Take 6 calcium gluconate tablets (batch number: 240802), use 900 mL of water as the dissolution medium, use the paddle method, and rotate at 50 rpm. Take samples at 5 min, 10 min, 15 min, 30 min, 45 min and 60 min, filter, and take the filtrate as the test solution.

[0031] 4. Determination Method: Accurately measure 10 μl of the test solution and the reference solution, and inject them separately into the ion chromatograph, recording the chromatograms. Calculate the dissolution amount using a linear regression equation and plot the dissolution curve. The results of the dissolution curve determination are shown in [Figure Number]. Figure 1 .

[0032] 5. Results and conclusions: The self-made calcium gluconate tablets showed good intra-batch homogeneity.

[0033] Example 2: Specificity Verification

[0034] 1. Solution preparation:

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

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

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

[0038] 2. Chromatographic conditions:

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

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

[0041] 4. Results and Conclusions: The blank solvent and blank excipient solution did not interfere with the main peak position of the reference solution, indicating good method specificity. See the results below. Figure 2 .

[0042] Example 3: Linearity and Range Verification

[0043] 1. Solution preparation:

[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 the "Specificity" section, place them in 10 mL volumetric flasks, dilute with water to the mark, 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 (4×250mm); eluent: 20mmol / L methanesulfonic acid aqueous solution; flow rate: 1.0mL / min; detector: conductivity detector; column temperature: 30℃.

[0047] 3. Determination method: Under the determined chromatographic conditions, accurately measure 1–5 units of the linear solution and inject them into the ion chromatograph, recording the chromatograms. Plot the peak area against concentration and perform linear regression.

[0048] 4. Results and Conclusions: Within the concentration range of 0.1113 mg / mL to 0.6680 mg / mL, calcium gluconate concentration showed a good linear relationship with peak area. The linear regression equation was y = 11.884x - 0.2664, and the correlation coefficient R² = 0.999. See the results below. Figure 3 Example 4: Recovery Rate Verification

[0049] 1. Solution preparation:

[0050] Preparation of reference solutions: Accurately measure 0.5, 2.0, and 3.0 ml of the linear stock solution under the "Specificity" section, place them in 10 ml volumetric flasks, dilute to the mark with dissolution medium, and shake well to obtain the reference solution.

[0051] Preparation of test solutions: Accurately measure 0.5 ml of the blank excipient stock solution under the "Specificity" section and place it in a 10 ml volumetric flask. Then, accurately add 0.5 ml, 2.0 ml, and 3.0 ml of the reference stock solution under the "Specificity" section, respectively. Dilute with water to the mark, shake well, filter, and collect the filtrate to obtain spiking solutions with dissolution concentrations of 20%, 80%, and 120%. Prepare three replicates for each concentration, for a total of nine replicates.

[0052] 2. Chromatographic conditions:

[0053] Chromatographic column: Dionex IonPac CS12A cation exchange column (4×250mm); eluent: 20mmol / L methanesulfonic acid aqueous solution; flow rate: 1.0mL / min; detector: conductivity detector; column temperature: 30℃.

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

[0055] 4. Results and Conclusions: The recovery rates of calcium gluconate were 98%–102% within the dissolution concentration range of 20%–120%, with an average recovery rate of 100.3% for the nine samples and an RSD of 1.15%, indicating good recovery of the method. The results are shown in Table 1.

[0056] Table 1 Results of the recovery rate test

[0057]

[0058] Example 5: Sample injection precision verification

[0059] 1. Solution preparation:

[0060] Preparation of test solutions: Accurately weigh 11.23 mg, 44.44 mg and 66.68 mg of calcium gluconate raw material respectively, place them in 100 ml volumetric flasks, dilute with water to the mark, shake well, and obtain solutions with dissolution concentrations of 20%, 80% and 120%.

[0061] 2. Chromatographic conditions:

[0062] Chromatographic column: Dionex IonPac CS12A cation exchange column (4×250mm); eluent: 20mmol / L methanesulfonic acid aqueous solution; flow rate: 1.0mL / min; detector: conductivity detector; column temperature: 30℃.

[0063] 3. Determination method: Under the determined chromatographic conditions, accurately measure the test solution, inject it into the chromatograph, and record the chromatogram. Inject each concentration six times consecutively and record the peak area.

[0064] 4. Results and Conclusions: The peak area RSDs of solutions at concentration levels of 20%–120% were 0.31%, 0.28%, and 0.60%, respectively, all not exceeding 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. Solution preparation:

[0070] Preparation of reference solutions: Accurately measure 0.5, 2.0, and 3.0 ml of the linear stock solution under the "Specificity" section, place them in 10 ml volumetric flasks, dilute to the mark with dissolution medium, and shake well.

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

[0072] 2. Chromatographic conditions:

[0073] Chromatographic column: Dionex IonPac CS12A cation exchange column (4×250mm); eluent: 20mmol / L methanesulfonic acid aqueous solution; flow rate: 1.0mL / min; detector: conductivity detector; column temperature: 30℃.

[0074] 3. Determination method: Under the determined chromatographic conditions, accurately measure 10 μl of the reference solution and the test solution, 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 six samples were 0.82% and 0.16%, respectively, both less than 2%, indicating good reproducibility of the method. The results are shown in Table 3.

[0076] Table 3 Results of Repeatability Tests

[0077]

[0078]

[0079] Example 7: Solution Stability Verification

[0080] 1. Solution preparation:

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

[0082] 2. Chromatographic conditions:

[0083] Chromatographic column: Dionex IonPac CS12A cation exchange column (4×250mm); eluent: 20mmol / L methanesulfonic acid aqueous solution; flow rate: 1.0mL / min; detector: conductivity detector; column temperature: 30℃.

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

[0085] 4. Results and Conclusions: The RSD of the 40% solution was 0.82%, and the RSD of the 100% solution was 0.36%, indicating that the solution remained stable within 10 hours 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. Solution preparation:

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

[0092] Preparation of test solution: Take 1 tablet of this product for dissolution test. Take samples from the dissolution vessel at 5 min and 60 min, filter, and collect the filtrate.

[0093] 2. Chromatographic conditions:

[0094] Chromatographic column: Dionex IonPac CS12A cation exchange column (4×250mm); eluent: 20mmol / L methanesulfonic acid aqueous solution; flow rate: 1.0mL / min; detector: conductivity detector; column temperature: 30℃.

[0095] 3. Determination method: Under the determined chromatographic conditions or with minor modifications, accurately measure 10 μl of the reference solution and the test solution, inject them into the ion chromatogram, record the chromatogram, and calculate the dissolution amount using a linear regression equation.

[0096] 4. Results and Conclusions: When the concentration of methanesulfonic acid and the flow rate of the eluent changed by ±10%, the RSD of dissolution was 1.05% and 0.75%, respectively, both less than 2.0%. Minor changes in chromatographic conditions had no significant effect on the determination, and the method showed good robustness. The results are shown in Table 5.

[0097] Table 5 Durability Test Results

[0098]

[0099]

Claims

1. A method for determining the dissolution curve of calcium gluconate tablets, characterized in that, The determination was performed using ion chromatography, with the following conditions: a conductivity detector as the detector, a Dionex IonPac CS12A cation exchange column as the chromatographic column, and a 18-22 mmol / L methanesulfonic acid solution as the eluent.

2. The determination method according to claim 1, characterized in that, The rinsing solution is a 20 mmol / L methanesulfonic acid solution.

3. The determination method according to claim 1, characterized in that, The flow rate of the rinsing solution is 0.9~1.1 mL / min.

4. The determination method according to claim 3, characterized in that, The flow rate of the rinsing solution is 1.0 mL / min.

5. The determination method according to claim 1, characterized in that, The column temperature of the chromatographic column is 25℃~35℃.

6. The determination method according to claim 5, characterized in that, The column temperature of the chromatographic column is 30℃.

7. A method for determining the dissolution curve of calcium gluconate tablets, characterized in that, Includes the following steps: (1) Preparation of reference solution: Take an appropriate amount of calcium gluconate reference standard, accurately weigh it, dissolve it in water and dilute it quantitatively to prepare a solution containing approximately 0.1 mg, 0.4 mg and 0.7 mg per 1 mL respectively; (2) Preparation of test solution: Take 6 calcium gluconate tablets, use 900 mL of water as the dissolution medium, use the paddle method, and rotate at 50 revolutions per minute. Take samples at 5 min, 10 min, 15 min, 30 min, 45 min and 60 min, filter, and take the filtrate as the test solution. (3) 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℃; (4) Determination method and result calculation: Accurately measure 10 µL each of the above reference solution and test solution, inject them into the ion chromatograph, and record the chromatograms; plot the peak area against the concentration of the reference solution, and perform linear regression, correlation coefficient R 2 Not less than 0.998; calculate the dissolution amount using a linear regression equation and plot the dissolution curve.

8. The method for determining the dissolution curve of calcium gluconate tablets according to any one of claims 1-7, characterized in that, This method is used to determine the dissolution curves of calcium gluconate tablet raw materials and related preparations.

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