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zhy52019鐵蟲 (小有名氣)
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[求助]
USP33-NF28中鹽酸二甲雙胍緩釋片的標(biāo)準(zhǔn) 已有2人參與
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zhy52019
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sky3d
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zhy52019: 金幣+1, ★有幫助, 謝謝啦 2014-11-15 13:22:03
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zhy52019: 金幣+1, ★有幫助, 謝謝啦 2014-11-15 13:22:03
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USP32 Metformin Hydrochloride Extended-Release Tablets » Metformin Hydrochloride Extended-Release Tablets contain not less than 90.0 percent and not more than 110.0 percent of the labeled amount of metformin hydrochloride (C4H11N5·HCl). Packaging and storage— Preserve in well-closed, light-resistant containers, and store at controlled room temperature. Labeling— When more than one Dissolution Test is given, the labeling states the Dissolution Test used only if Test 1 is not used. USP Reference standards 11— USP Metformin Hydrochloride RS . USP Metformin Related Compound B RS . USP Metformin Related Compound C RS . Identification— The retention time of the major peak in the chromatogram of the Assay preparation corresponds to that in the chromatogram of the Standard preparation, as obtained in the Assay. Change to read: Dissolution 711— test 1— Medium: pH 6.8 phosphate buffer prepared by dissolving 6.8 g of monobasic potassium phosphate in 1000 mL of water and adjusting with 0.2 N sodium hydroxide to a pH of 6.8 ± 0.1; 1000 mL. Apparatus 2: 100 rpm, for Tablets labeled to contain 500 mg. Apparatus 1: 100 rpm, for Tablets labeled to contain 750 mg. Times: 1, 3, and 10 hours. Procedure— Determine the amount of C4H11N5·HCl dissolved by UV absorption at the wavelength of maximum absorbance at about 232 nm on portions of the solution under test passed through a 0.45-µm hydrophilic polyethylene filter, suitably diluted with Medium, if necessary, in comparison with a Standard solution having a known concentration of USP Metformin Hydrochloride RS in the same Medium. Calculate the amount of metformin hydrochloride (C4H11N5·HCl), in percentage, released at each time point by the formula: in which C is the concentration, in mg per mL, of the Standard solution; AU and AS are the absorbances of the solution under test and the Standard solution, respectively; V is the initial volume, in mL, of Medium in the vessel; VS is the volume, in mL, withdrawn from the vessel for previous samplings; C60 is the concentration, in mg per mL, of metformin hydrochloride in the Medium determined at 1 hour; C180 is the concentration, in mg per mL, of metformin hydrochloride in the Medium determined at 3 hours; 100 is the conversion factor to percentage; and L is the Tablet label claim, in mg. Tolerances— The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. Time (hours) 500-mg Tablet, Amount dissolved 750-mg Tablet, Amount dissolved 1 between 20% and 40% between 22% and 42% 3 between 45% and 65% between 49% and 69% 10 not less than 85% not less than 85% test 2— If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 2. Medium: Prepare as directed for Medium in Test 1; 1000 mL. Apparatus 2: 100 rpm. Times: 1, 2, 6, and 10 hours. Procedure— Determine the amount of C4H11N5·HCl dissolved by UV absorption at the wavelength of maximum absorbance at about 232 nm on portions of the solution under test passed through a 0.45-µm polyethylene filter, suitably diluted with Medium, if necessary, in comparison with a Standard solution having a known concentration of USP Metformin Hydrochloride RS in the same Medium. Calculate the content of metformin hydrochloride (C4H11N5·HCl), Ct, in mg per mL, in the Medium at each time point, t, by the formula: in which AU and AS are the absorbances of the solution under test and the Standard solution, respectively; CS is the concentration of metformin hydrochloride, in mg per mL, in the Standard solution; and DU is the dilution factor of the solution under test. Calculate the percentage of metformin hydrochloride (C4H11N5·HCl) dissolved at each time point by the following formulas: Percentage dissolved at the first time point (1 hour): in which C1 is the content of metformin hydrochloride, in mg per mL, in the Medium at the first time interval; 1000 is the volume, in mL, of Medium; 100 is the conversion factor to percentage; and L is the Tablet label claim, in mg. Percentage dissolved at the second time point (2 hours): in which C2 is the content of metformin hydrochloride, in mg per mL, in the Medium at the second time interval; 1000 is the volume, in mL, of Medium; SV1 is the volume, in mL, of the sample withdrawn at 1 hour; C1 is the content of metformin hydrochloride, in mg per mL, in the Medium at 1 hour; 100 is the conversion factor to percentage; and L is the Tablet label claim, in mg. Percentage dissolved at the nth time point: in which Cn is the content of metformin hydrochloride, in mg per mL, in the Medium at the nth time interval; n is the time interval of interest; SV is the volume, in mL, of sample withdrawn at each time interval; C1, C2, C3, ... Cn–1 is the content of metformin hydrochloride, in mg per mL, in the Medium at each time interval; 100 is the conversion factor to percentage; and L is the Tablet label claim, in mg. Tolerances— The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. Time (hours) Amount dissolved 1 between 20% and 40% 2 between 35% and 55% 6 between 65% and 85% 10 not less than 85% test 3— If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 3. Medium, Apparatus, and Procedure— Proceed as directed for Test 1. Times: 1, 2, 5, and 12 hours for Tablets labeled to contain 500 mg; and 1, 3, and 10 hours for Tablets labeled to contain 750 mg. Procedure— Determine the amount of C4H11N5·HCl dissolved by UV absorption at the wavelength of maximum absorbance at about 232 nm on portions of the solution under test passed through a 0.45-µm hydrophilic polyethylene filter, suitably diluted with Medium, if necessary, in comparison with a Standard solution having a known concentration of USP Metformin Hydrochloride RS in the same Medium. Calculate the amount of metformin hydrochloride (C4H11N5·HCl), in percentage, released at each time point by the formula: in which C is the concentration, in mg per mL, of the Standard solution; AU and AS are the absorbances of the solution under test and the Standard solution, respectively; V is the initial volume, in mL, of Medium in the vessel; VS is the volume, in mL, withdrawn from the vessel for previous samplings; C60 is the concentration, in mg per mL, of metformin hydrochloride in the Medium determined at 1 hour; C120 is the concentration, in mg per mL, of metformin hydrochloride in the Medium determined at 2 hours; C300 is the concentration, in mg per mL, of metformin hydrochloride in the Medium determined at 5 hours; 100 is the conversion factor to percentage; and L is the Tablet label claim, in mg. Tolerances— The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. for tablets labeled to contain 500 mg: Time (hours) Amount dissolved 1 between 20% and 40% 2 between 35% and 55% 5 between 60% and 80% 12 not less than 85% for tablets labeled to contain 750 mg: Time (hours) Amount dissolved 1 between 22% and 42% 3 between 49% and 69% 10 not less than 85% test 4— If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 4. Medium: Prepare as directed for Medium in Test 1; 1000 mL. Apparatus 2: 100 rpm. Times: 1, 3, 6, and 10 hours. Procedure— Determine the amount of C4H11N5·HCl dissolved by UV absorption at the wavelength of maximum absorbance at about 250 nm (shoulder) on portions of the solution under test passed through a 0.45-µm polyethylene filter, suitably diluted with Medium, if necessary, in comparison with a Standard solution having a known concentration of USP Metformin Hydrochloride RS in the same Medium. Calculate the content of metformin hydrochloride (C4H11N5·HCl), Ct, in mg per mL, in the Medium at each time point, t, by the formulas specified in Test 2. Tolerances— The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. Time (hours) Amount dissolved 1 between 20% and 40% 3 between 45% and 65% 6 between 65% and 85% 10 not less than 85% test 5— If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 5. Medium: pH 6.8 phosphate buffer prepared by dissolving 6.8 g of monobasic potassium phosphate in 1000 mL of water and adjusting with 0.2 N sodium hydroxide to a pH of 6.8 ± 0.1; 900 mL, deaerated. Apparatus 1: 100 rpm, with the vertical holder described below. Times: 2, 8, and 16 hours. Procedure— Place a vertical sample holder into each basket (see Figures 1 and 2). Place one Tablet inside the sample holder, making sure that the Tablets are vertical at the bottom of the baskets. Determine the amount of C4H11N5·HCl dissolved by UV absorption at the wavelength of maximum absorbance at about 250 nm on portions of the solution under test passed through a 0.45-µm polyethylene filter, suitably diluted with Medium, if necessary, in comparison with a Standard solution having a known concentration of USP Metformin Hydrochloride RS in the same Medium. Calculate the content of metformin hydrochloride (C4H11N5·HCl), Ct, in mg per mL, in the Medium at each time point, t, by the formulas specified in Test 2. Figure 1 Figure 2 Tolerances— The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. Time (hours) 500-mg Tablet, Amount dissolved 1000-mg Tablet, Amount dissolved 2 not more than 30% not more than 30% 8 between 60% and 85% between 65% and 90% 16 not less than 90% not less than 90% test 6— If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 6. Medium: pH 6.8 phosphate buffer prepared by dissolving 6.8 g of monobasic potassium phosphate in 1000 mL of water and adjusting with 0.2 N sodium hydroxide to a pH of 6.8 ± 0.05; 1000 mL, deaerated. Apparatus 2: 100 rpm, with USP sinker, if necessary. Procedure— Determine the amount of C4H11N5·HCl dissolved by UV absorption at the wavelength of maximum absorbance at about 233 nm on portions of the solution under test passed through a 0.45-µm hydrophilic polyethylene filter, suitably diluted with Medium, if necessary, in comparison with a Standard solution having a known concentration of USP Metformin Hydrochloride RS in the same Medium. Calculate the amount of metformin hydrochloride (C4H11N5·HCl), in percentage, released at each time point by the formula: in which C is the concentration, in mg per mL, of the Standard solution; AU and AS are the absorbances of the solution under test and the Standard solution, respectively; V is the initial volume, in mL, of Medium in the vessel; VS is the volume, in mL, withdrawn from the vessel for previous samplings; C60 is the concentration, in mg per mL, of metformin hydrochloride in the Medium determined at 1 hour; C180 is the concentration, in mg per mL, of metformin hydrochloride in the Medium determined at 3 hours; C600 is the concentration, in mg per mL, of metformin hydrochloride in the Medium determined at 10 hours; 100 is the conversion factor to percentage; and L is the Tablet label claim, in mg. Tolerances— The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. Time (hours) 500-mg Tablet, Amount dissolved 750-mg Tablet, Amount dissolved 1 between 20% and 40% between 20% and 40% 3 between 45% and 65% between 45% and 65% 10 not less than 85% not less than 85% test 7— If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 7. Medium —Prepare as directed for Medium in Test 1; 1000 mL. Apparatus 2: 50 rpm, with USP sinker, for Tablets labeled to contain 500 mg. Apparatus 1: 100 rpm, for Tablets labeled to contain 750 mg. Times: 1, 3, and 10 hours. Procedure— Determine the amount of C4H11N5·HCl dissolved by UV absorption at the wavelength of maximum absorbance at about 232 nm on portions of the solution under test passed through a suitable 0.45-µm filter, suitably diluted with Medium, if necessary, in comparison with a Standard solution having a known concentration of USP Metformin Hydrochloride RS in the same Medium. Calculate the amount of metformin hydrochloride (C4H11N5·HCl), in percentage, released at each time point by the formula: in which C is the concentration, in mg per mL, of the Standard solution; AU and AS are the absorbances of the solution under test and the Standard solution, respectively; V is the initial volume, in mL, of Medium in the vessel; VS is the volume, in mL, withdrawn from the vessel for previous samplings; C60 is the concentration, in mg per mL, of metformin hydrochloride in the Medium determined at 1 hour; C180 is the concentration, in mg per mL, of metformin hydrochloride in the Medium determined at 3 hours; C600 is the concentration, in mg per mL, of metformin hydrochloride in the Medium determined at 10 hours; 100 is the conversion factor to percentage; and L is the Tablet label claim, in mg. Tolerances— The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. Time (hours) 500-mg Tablet, Amount dissolved 750-mg Tablet, Amount dissolved 1 between 20% and 40% between 20% and 40% 3 between 45% and 65% between 40% and 60% 10 not less than 85% not less than 80% test 8 —If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 8. Medium —Prepare as directed for Medium in Test 1; 1000 mL. Apparatus 2: 100 rpm, with sinker, for Tablets labeled to contain 500 mg. Apparatus 1: 100 rpm, for Tablets labeled to contain 750 mg. Times: 1, 2, 6, and 10 hours. Procedure— Determine the amount of C4H11N5·HCl dissolved by UV absorption at the wavelength of maximum absorbance at about 232 nm on portions of the solution under test passed through a suitable 0.45-µm filter, suitably diluted with Medium, if necessary, in comparison with a Standard solution having a known concentration of USP Metformin Hydrochloride RS in the same Medium. Calculate the amount of metformin hydrochloride (C4H11N5·HCl), in percentage, released at each time point by the formula (1): in which C is the concentration, in mg per mL, of the Standard solution; AU and AS are the absorbances of the solution under test and the Standard solution, respectively; V is the initial volume, in mL, of Medium in the vessel; VS is the volume, in mL, withdrawn from the vessel for previous samplings; C60 is the concentration, in mg per mL, of metformin hydrochloride in the Medium determined at 1 hour; C120 is the concentration, in mg per mL, of metformin hydrochloride in the Medium determined at 2 hours; C360 is the concentration, in mg per mL, of metformin hydrochloride in the Medium determined at 6 hours; C600 is the concentration, in mg per mL, of metformin hydrochloride in the Medium determined at 10 hours; 100 is the conversion factor to percentage; and L is the tablet label claim, in mg. Tolerances— The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. Time (hours) 500-mg Tablet, Amount dissolved 750-mg Tablet, Amount dissolved 1 between 20% and 40% between 20% and 40% 2 between 30% and 50% between 35% and 55% 6 between 65% and 85% between 75% and 95% 10 not less than 85% not less than 85% Test 9— If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 9. Medium: 0.05 M phosphate buffer, pH 6.8; 1000 mL. Apparatus 2: 100 rpm. Times: 1, 5, 12, and 20 hours for Tablets labeled to contain 500 mg; and 1, 4, 10, and 24 hours for Tablets labeled to contain 750 mg. Standard solution— Transfer about 50 mg, accurately weighed, of USP Metformin Hydrochloride RS to a 100-mL volumetric flask, and dissolve in and dilute with Medium to volume. Test solution— Pass a portion of the solution under test through a filter having a porosity of 0.45 µm. Procedure— Determine the amount of C4H11N5·HCl dissolved by UV absorption at the wavelength of maximum absorbance at about 232 nm on portions of the Test solution in comparison with the Standard solution, using a 0.01-cm flow cell and Medium as the blank. Calculate the amount of metformin hydrochloride (C4H11N5·HCl), in percentage, released at each time point by the formula (2), in which C is the concentration, in mg per mL, of the Standard solution; AU and AS are the absorbances of the Test solution and the Standard solution, respectively; V is the initial volume, in mL, of Medium in the vessel; VS is the volume, in mL, withdrawn from the vessel for previous samplings; C1 is the concentration, in mg per mL, of metformin hydrochloride in Medium determined at the first timepoint; C2 is the concentration, in mg per mL, of metformin hydrochloride in Medium determined at the second timepoint; C3 is the concentration, in mg per mL, of metformin hydrochloride in Medium determined at the third timepoint; C4 is the concentration, in mg per mL, of metformin hydrochloride in Medium determined at the fourth timepoint; 100 is the conversion factor to percentage; and L is the Tablet label claim, in mg. Tolerances— The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. For tablets labeled to contain 500 mg: Time (hours) Amount dissolved 1 between 20% and 40% 5 between 45% and 65% 12 between 70% and 90% 20 not less than 85% For tablets labeled to contain 750 mg: Time (hours) Amount dissolved 1 between 20% and 45% 4 between 45% and 70% 10 between 70% and 95% 24 not less than 85% 6 Uniformity of dosage units 905: meet the requirements. Chromatographic purity— Mobile phase and Chromatographic system— Prepare as directed in the Assay. Test solution— Use the Assay preparation, prepared as directed in the Assay. Procedure— Inject a volume (about 10 µL) of the Test solution into the chromatograph, record the chromatogram, and measure all of the peak responses. Calculate the percentage of each impurity in the portion of Tablets taken by the formula: 100(ri / rs) in which ri is the peak response for each impurity, and rs is the sum of the responses of all the peaks: not more than 0.1% of any individual impurity is found, and not more than 0.6% of total impurities is found. Disregard any peak less than 0.05%, and disregard any peak observed in the blank. Assay— Buffer solution— Transfer 1.0 g each of sodium heptanesulfonate and sodium chloride to a 2000-mL volumetric flask, add 1800 mL of water, and mix. Adjust with 0.06 M phosphoric acid to a pH of 3.85, and dilute with water to volume. Mobile phase— Prepare a filtered and degassed mixture of Buffer solution and acetonitrile (90:10). Make adjustments if necessary (see System Suitability under Chromatography 621). [note—To improve the separation, the composition may be changed to 95:5, if necessary.] Diluent— Use a 1.25% solution of acetonitrile in water. Standard preparation— Dissolve an accurately weighed quantity of USP Metformin Hydrochloride RS in Diluent, and dilute quantitatively, and stepwise if necessary, with Diluent to obtain a solution having a known concentration of about (L/4000) mg per mL, where L is the labeled quantity, in mg, of metformin hydrochloride in each Tablet. System suitability preparation— Dissolve suitable quantities of USP Metformin Related Compound B RS and USP Metformin Related Compound C RS in Diluent to obtain a solution containing about 12.5 µg of each per mL. Pipet 0.5 mL of this solution into a 50-mL volumetric flask, and dilute with the Standard preparation to volume. Assay stock preparation— Weigh and finely powder not fewer than 10 Tablets. Transfer an accurately weighed portion of the powder, equivalent to the average Tablet weight, to a homogenization vessel, and accurately add 500 mL of 10% acetonitrile solution. Alternately, homogenize and allow to soak until the sample is fully homogenized. [note—A suggested homogenization sequence is as follows: Homogenize the sample using 5 pulses, each of 5 second, at about 20,000 rpm; allow to soak for 2 minutes. Repeat these steps a further two times.] Assay preparation— Pass a portion of the Assay stock preparation through a filter having a 0.45-µm porosity, discarding the first 3 mL of filtrate. Transfer 25 mL of the filtrate to a 200-mL volumetric flask, and dilute with water to volume. Chromatographic system (see Chromatography 621)— The liquid chromatograph is equipped with a 218-nm detector and a 3.9-mm × 30-cm column that contains 10-µm packing L1. The flow rate is about 1.0 mL per minute. The column temperature is maintained at 30. Chromatograph the System suitability preparation, and record the peak responses as directed for Procedure: the relative retention times are about 0.86 for metformin related compound B, 1.0 for metformin, and about 2.1 to 2.3 for metformin related compound C [note—This impurity can have a variable retention time; the composition of the Mobile phase may be changed to 95:5, if metformin related compound C elutes at a relative retention time of less than 2.1.]; the resolution, R, between peaks due to metformin related compound B and metformin is not less than 1.5; the tailing factor for the metformin peak is not less than 0.8 and not more than 2.0; and the relative standard deviation for replicate injections is not more than 1.5% for the metformin peak and not more than 10% for each of the peaks due to metformin related compound B and metformin related compound C. Procedure— Separately inject equal volumes (about 10 µL) of the Standard preparation and the Assay preparation into the chromatograph, carrying out the run until after the elution locus of metformin related compound C; record the chromatograms; and measure the responses for the major peaks. Calculate the quantity, in mg per Tablet, of metformin hydrochloride (C4H11N5·HCl) by the formula: C(V/W)TD(rU / rS) in which C is the concentration, in mg per mL, of USP Metformin Hydrochloride RS in the Standard preparation; V is the volume, in mL, of the Assay stock preparation; W is the weight, in mg, of sample used to prepare the Assay stock preparation; T is the average Tablet weight, in mg; D is the dilution factor of the Assay preparation; and rU and rS are the peak responses obtained from the Assay preparation and the Standard preparation, respectively. Auxiliary Information— Please check for your question in the FAQs before contacting USP. Topic/Question Contact Expert Committee Monograph Elena Gonikberg, Ph.D. Senior Scientist 1-301-816-8251 (MDGRE05) Monograph Development-Gastrointestinal Renal and Endocrine Reference Standards Lili Wang, Technical Services Scientist 1-301-816-8129 RSTech@usp.org 711 Margareth R.C. Marques, Ph.D. Senior Scientist 1-301-816-8106 (BPC05) Biopharmaceutics05 USP32–NF27 Page 2907 USP32–NF27 Supplement : No. 1 Page 4073 Pharmacopeial Forum: Volume No. 35(1) Page 76 |
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sky3d
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【答案】應(yīng)助回帖
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zhy52019: 金幣+1, ★有幫助, 謝謝親的應(yīng)助，嘿嘿 2014-11-15 13:23:07
zhy52019: 金幣+1, ★有幫助, 謝謝親的應(yīng)助，嘿嘿 2014-11-15 13:23:07
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USP34 沒有找到33 Metformin Hydrochloride Extended-Release Tablets DEFINITION Metformin Hydrochloride Extended-Release Tablets contain NLT 90.0% and NMT 110.0% of the labeled amount of metformin hydrochloride (C4H11N5·HCl). IDENTIFICATION • The retention time of the major peak from the Sample solution corresponds to that from the Standard solution, as obtained in the Assay. ASSAY • Procedure Buffer solution: 0.5 g/L of sodium heptanesulfonate and 0.5 g/L of sodium chloride in water. Prior to final dilution, adjust with 0.06 M phosphoric acid to a pH of 3.85. Mobile phase: Acetonitrile and Buffer solution (1:9). [Note—To improve the separation, the composition of acetonitrile and Buffer solution may be changed to 1:19, if necessary. ] Diluent: 1.25% solution of acetonitrile in water Standard solution: (L/4000) mg/mL of USP Metformin Hydrochloride RS in Diluent, where L is the labeled quantity, in mg, of metformin hydrochloride in each Tablet System suitability stock solution: 12.5 µg/mL of each of USP Metformin Related Compound B RS and USP Metformin Related Compound C RS in Diluent System suitability solution: Dilute 0.5 mL of the System suitability stock solution with the Standard solution to 50 mL. Sample stock solution: Finely powder NLT 10 Tablets. Transfer powder, equivalent to the average Tablet weight, to a homogenization vessel, and accurately add 500 mL of 10% acetonitrile solution. Alternately, homogenize and allow to soak until the sample is fully homogenized. [Note—A suggested homogenization sequence is as follows. Homogenize the sample using five pulses, each of 5 s, at about 20,000 rpm, and allow to soak for 2 min. Repeat these steps two additional times. ] Sample solution: Pass a portion of the Sample stock solution through a suitable filter of 0.45-µm pore size, discarding the first 3 mL of filtrate. Transfer 25 mL of the filtrate to a 200-mL volumetric flask, and dilute with water to volume. Chromatographic system (See Chromatography 621, System Suitability.) Mode: LC Detector: UV 218 nm Column: 3.9-mm × 30-cm; 10-µm packing L1 Column temperature: 30 Flow rate: 1 mL/min Injection size: 10 µL Run time: Until after the elution locus of metformin related compound C System suitability Sample: System suitability solution [Note—The relative retention times for metformin related compound B, metformin, and metformin related compound C are 0.86, 1.0, and 2.1–2.3, respectively. Metformin related compound C can have a variable retention time. The composition of the Mobile phase may be changed to 1:19, if it elutes at a relative retention time of less than 2.1. ] Suitability requirements Resolution: NLT 1.5 between peaks due to metformin related compound B and metformin Tailing factor: NLT 0.8 and NMT 2.0 for the metformin peak Relative standard deviation: NMT 1.5% for the metformin peak and NMT 10% for each of the peaks due to metformin related compound B and metformin related compound C Analysis Samples: Standard solution and Sample solution Calculate the percentage of C4H11N5·HCl in the portion of Tablets taken: Result = (rU/rS) × (CS/CU) × 100 rU = = peak response from the Sample solution rS = = peak response from the Standard solution CS = = concentration of USP Metformin Hydrochloride RS in the Standard solution (mg/mL) CU = = nominal concentration of metformin hydrochloride in the Sample solution Acceptance criteria: 90.0%–110.0% PERFORMANCE TESTS • Dissolution 711 Test 1 Medium: pH 6.8 phosphate buffer (6.8 g of monobasic potassium phosphate in 1000 mL of water; adjust with 0.2 N sodium hydroxide to a pH of 6.8 ± 0.1); 1000 mL Apparatus 1: 100 rpm for Tablets labeled to contain 750 mg Apparatus 2: 100 rpm for Tablets labeled to contain 500 mg Times: 1, 3, and 10 h Detector: UV 232 nm Standard solution: USP Metformin Hydrochloride RS in Medium Sample solution: Pass a portion of the solution under test through a suitable hydrophilic polyethylene filter of 0.45-µm pore size. Dilute, if necessary, with Medium to a concentration similar to the Standard solution. Analysis: Calculate the percentage of C4H11N5·HCl released at each time point: Result = [(AU/AS) × CS × (V VS) + (C60 × VS) + (C180 × VS) × 100]/L AU = = absorbance of the Sample solution AS = = absorbance of the Standard solution CS = = concentration of the Standard solution (mg/mL) V = = initial volume of Medium in the vessel (mL) VS = = volume withdrawn from the vessel for previous samplings (mL) C60 = = concentration of metformin hydrochloride in Medium determined at 1 h (mg/mL) C180 = = concentration of metformin hydrochloride in Medium determined at 3 h (mg/mL) L = = label claim (mg/Tablet) Tolerances: The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. Time (h) Amount Dissolved, 500-mg Tablet Amount Dissolved, 750-mg Tablet 1 20%–40% 22%–42% 3 45%–65% 49%–69% 10 NLT 85% NLT 85% Test 2: If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 2. Medium: Prepare as directed for Test 1; 1000 mL Apparatus 2: 100 rpm Times: 1, 2, 6, and 10 h Detector: UV 232 nm Standard solution: USP Metformin Hydrochloride RS in Medium Sample solution: Pass a portion of the solution under test through a suitable polyethylene filter of 0.45-µm pore size. Dilute, if necessary, with Medium to a concentration that is similar to the Standard solution. Analysis: Calculate, in mg/mL, the content of C4H11N5·HCl, Ct, in Medium at each time point, t: Result = [AU × CS × DU]/AS AU = = absorbance of the Sample solution CS = = concentration of metformin hydrochloride in the Standard solution (mg/mL) DU = = dilution factor of the solution under test AS = = absorbance of the Standard solution Calculate the percentage of C4H11N5·HCl dissolved at each time point by the following formulas. Percentage dissolved at the first time point (1 h): Result = [C1 × V × 100]/L C1 = = content of metformin hydrochloride in Medium at the first time interval (mg/mL) V = = volume of Medium, 1000 mL L = = label claim (mg/Tablet) Percentage dissolved at the second time point (2 h): Result = [C2 × (V SV1) + C1 × SV1 × 100]/L C2 = = content of metformin hydrochloride in Medium at the second time interval (mg/mL) V = = volume of Medium, 1000 mL SV1 = = volume of the sample withdrawn at 1 h (mL) C1 = = content of metformin hydrochloride in Medium at 1 h (mg/mL) L = = label claim (mg/Tablet) Percentage dissolved at the nth time point: Result = {Cn × [V (n 1)VS] + (C1 + C2 + … + Cn1) × VS × 100}/L Cn = = content of metformin hydrochloride in Medium at the nth time interval (mg/mL) V = = volume of Medium, 1000 mL n = = time interval of interest VS = = volume of sample withdrawn at each time interval (mL) C = = as C1, C2, C3, … Cn–1, the content of metformin hydrochloride in Medium at each time interval (mg/mL) L = = label claim (mg/Tablet) Tolerances: The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. Time (h) Amount Dissolved 1 20%–40% 2 35%–55% 6 65%–85% 10 NLT 85% Test 3: If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 3. Medium, Apparatus 1, Apparatus 2, and Analysis: Proceed as directed in Test 1. Times: 1, 2, 5, and 12 h for Tablets labeled to contain 500 mg; and 1, 3, and 10 h for Tablets labeled to contain 750 mg Detector: UV 232 nm Standard solution: USP Metformin Hydrochloride RS in Medium Sample solution: Pass a portion of the solution under test through a suitable hydrophilic polyethylene filter of 0.45-µm pore size. Dilute, if necessary, with Medium to a concentration similar to the Standard solution. Analysis: Calculate the percentage of C4H11N5·HCl released at each time point: Result = {[(AU/AS) × CS × (V VS) + (C60 × VS) + (C120 × VS) + (C300 × VS) + (C720 × VS)] × 100}/L AU = = absorbance of the Sample solution AS = = absorbance of the Standard solution CS = = concentration of the Standard solution (mg/mL) V = = initial volume of Medium in the vessel (mL) VS = = volume withdrawn from the vessel for previous samplings (mL) C60 = = concentration of metformin hydrochloride in Medium determined at 1 h (mg/mL) C120 = = concentration of metformin hydrochloride in Medium determined at 2 h (mg/mL) C300 = = concentration of metformin hydrochloride in Medium determined at 5 h (mg/mL) C720 = = concentration of metformin hydrochloride in Medium determined at 12 h (mg/mL) L = = label claim (mg/Tablet) Tolerances: The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. For Tablets Labeled to Contain 500 mg Time (h) Amount Dissolved 1 20%–40% 2 35%–55% 5 60%–80% 12 NLT 85% For Tablets Labeled to Contain 750 mg Time (h) Amount Dissolved 1 22%–42% 3 49%–69% 10 NLT 85% Test 4: If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 4. Medium: Prepare as directed for Test 1; 1000 mL Apparatus 2: 100 rpm Times: 1, 3, 6, and 10 h Detector: UV 250 nm (shoulder) Standard solution: USP Metformin Hydrochloride RS in Medium Sample solution: Pass a portion of the solution under test through a suitable filter of 0.45-µm pore size. Dilute, if necessary, with Medium to a concentration similar to the Standard solution. Analysis: Calculate, in mg/mL, the content of C4H11N5·HCl, Ct, in Medium at each time point, t, by the formulas specified in Test 2. Tolerances: The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. Time (h) Amount Dissolved 1 20%–40% 3 45%–65% 6 65%–85% 10 NLT 85% Test 5: If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 5. Medium: pH 6.8 phosphate buffer (6.8 g of monobasic potassium phosphate in 1000 mL of water; adjust with 0.2 N sodium hydroxide to a pH of 6.8 ± 0.1); 900 mL, deaerated Apparatus 1: 100 rpm, with the vertical holder described in Figure 1 and Figure 2 Figure 1 Figure 2 Times: 2, 8, and 16 h Detector: UV 250 nm Standard solution: USP Metformin Hydrochloride RS in Medium Sample solution: Pass a portion of the solution under test through a suitable filter of 0.45-µm pore size. Dilute, if necessary, with Medium to a concentration similar to the Standard solution. Analysis: Place a vertical sample holder into each basket (see Figures 1 and 2). Place 1 Tablet inside the sample holder, making sure that the Tablets are vertical at the bottom of the baskets. Calculate, in mg/mL, the content of C4H11N5·HCl, Ct, in Medium at each time point, t, by the formulas specified in Test 2. Tolerances: The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. Time (h) Amount Dissolved, 500-mg Tablet Amount Dissolved, 1000-mg Tablet 2 NMT 30% NMT 30% 8 60%–85% 65%–90% 16 NLT 90% NLT 90% Test 6: If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 6. Medium: pH 6.8 phosphate buffer (6.8 g of monobasic potassium phosphate in 1000 mL of water; adjust with 0.2 N sodium hydroxide to a pH of 6.8 ± 0.05); 1000 mL, deaerated Apparatus 2: 100 rpm, with USP sinker, if necessary Detector: UV 233 nm Standard solution: USP Metformin Hydrochloride RS in Medium Sample solution: Pass a portion of the solution under test through a suitable hydrophilic polyethylene filter of 0.45-µm pore size. Dilute, if necessary, with Medium to a concentration similar to the Standard solution. Analysis: Calculate the percentage of C4H11N5·HCl released at each time point: Result = {[(AU/AS) × CS × (V VS) + (C60 × VS) + (C180 × VS) + (C600 × VS)] × 100}/L AU = = absorbance of the Sample solution AS = = absorbance of the Standard solution CS = = concentration of the Standard solution (mg/mL) V = = initial volume of Medium in the vessel (mL) VS = = volume withdrawn from the vessel for previous samplings (mL) C60 = = concentration of metformin hydrochloride in Medium determined at 1 h (mg/mL) C180 = = concentration of metformin hydrochloride in Medium determined at 3 h (mg/mL) C600 = = concentration of metformin hydrochloride in Medium determined at 10 h (mg/mL) L = = label claim (mg/Tablet) Tolerances: The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. Time (h) Amount Dissolved, 500-mg Tablet Amount Dissolved, 750-mg Tablet 1 20%–40% 20%–40% 3 45%–65% 45%–65% 10 NLT 85% NLT 85% Test 7: If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 7. Medium: Prepare as directed in Test 1; 1000 mL Apparatus 1: 100 rpm for Tablets labeled to contain 750 mg Apparatus 2: 50 rpm, with USP sinker, for Tablets labeled to contain 500 mg Times: 1, 3, and 10 h Detector: UV 232 nm Standard solution: USP Metformin Hydrochloride RS in Medium Sample solution: Pass a portion of the solution under test through a suitable filter of 0.45-µm pore size. Dilute, if necessary, with Medium to a concentration similar to the Standard solution. Analysis: Calculate the percentage of C4H11N5·HCl released at each time point: Result = {[(AU/AS) × CS × (V VS) + (C60 × VS) + (C180 × VS) + (C600 × VS)] × 100}/L AU = = absorbance of the Sample solution AS = = absorbance of the Standard solution CS = = concentration of the Standard solution (mg/mL) V = = initial volume of Medium in the vessel (mL) VS = = volume withdrawn from the vessel for previous samplings (mL) C60 = = concentration of metformin hydrochloride in Medium determined at 1 h (mg/mL) C180 = = concentration of metformin hydrochloride in Medium determined at 3 h (mg/mL) C600 = = concentration of metformin hydrochloride in Medium determined at 10 h (mg/mL) L = = label claim (mg/Tablet) Tolerances: The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. Time (h) Amount Dissolved, 500-mg Tablet Amount Dissolved, 750-mg Tablet 1 20%–40% 20%–40% 3 45%–65% 40%–60% 10 NLT 85% NLT 80% Test 8: If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 8. Medium: Prepare as directed in Test 1; 1000 mL Apparatus 1: 100 rpm for Tablets labeled to contain 750 mg Apparatus 2: 100 rpm, with sinker, for Tablets labeled to contain 500 mg Times: 1, 2, 6, and 10 h Detector: UV 232 nm Standard solution: USP Metformin Hydrochloride RS in Medium Sample solution: Pass a portion of the solution under test through a suitable filter of 0.45-µm pore size. Dilute, if necessary, with Medium to a concentration similar to the Standard solution. Analysis: Calculate the percentage of C4H11N5·HCl released at each time point: Result = {[(AU/AS) × CS × (V VS) + (C60 × VS) + (C120 × VS) + (C360 × VS) + (C600 × VS)] × 100}/L AU = = absorbance of the Sample solution AS = = absorbance of the Standard solution CS = = concentration of the Standard solution (mg/mL) V = = initial volume of Medium in the vessel (mL) VS = = volume withdrawn from the vessel for previous samplings (mL) C60 = = concentration of metformin hydrochloride in Medium determined at 1 h (mg/mL) C120 = = concentration of metformin hydrochloride in Medium determined at 2 h (mg/mL) C360 = = concentration of metformin hydrochloride in Medium determined at 6 h (mg/mL) C600 = = concentration of metformin hydrochloride in Medium determined at 10 h (mg/mL) L = = label claim (mg/Tablet) Tolerances: The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. Time (h) Amount Dissolved, 500-mg Tablet Amount Dissolved, 750-mg Tablet 1 20%–40% 20%–40% 2 30%–50% 35%–55% 6 65%–85% 75%–95% 10 NLT 85% NLT 85% Test 9: If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 9. Medium: 0.05 M phosphate buffer, pH 6.8; 1000 mL Apparatus 1: 100 rpm, for Tablets labeled to contain 750 mg Apparatus 2: 100 rpm, for Tablets labeled to contain 500 mg Times: 1, 5, 12, and 20 h for Tablets labeled to contain 500 mg; and 1, 4, 10, and 24 h for Tablets labeled to contain 750 mg Standard solution: 0.5 mg/mL of USP Metformin Hydrochloride RS in Medium Sample solution: Pass a portion of the solution under test through a suitable filter of 0.45-µm pore size. Detector: UV 232 nm Path length: 0.01 cm, flow cell Blank: Medium Analysis: Calculate the percentage of C4H11N5·HCl released at each time point: Result = [(AU/AS) × CS × (V VS) + (C1 × VS) + (C2 × VS) + (C3 × VS) + (C4 × VS)] × 100/L AU = = absorbance of the Sample solution AS = = absorbance of the Standard solution CS = = concentration of the Standard solution (mg/mL) V = = initial volume of Medium in the vessel (mL) VS = = volume withdrawn from the vessel for previous samplings (mL) C1 = = concentration of metformin hydrochloride in Medium determined at the first time point (mg/mL) C2 = = concentration of metformin hydrochloride in Medium determined at the second time point (mg/mL) C3 = = concentration of metformin hydrochloride in Medium determined at the third time point (mg/mL) C4 = = concentration of metformin hydrochloride in Medium determined at fourth time point (mg/mL) L = = label claim (mg/Tablet) Tolerances: The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. For Tablets Labeled to Contain 500 mg Time (h) Amount Dissolved 1 20%–40% 5 45%–65% 12 70%–90% 20 NLT 85% For Tablets Labeled to Contain 750 mg Time (h) Amount Dissolved 1 20%–45% 4 45%–70% 10 70%–95% 24 NLT 85% Test 10: If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 10. Medium: 0.05 M phosphate buffer (prepared by dissolving 6.8 g of potassium dihydrogen phosphate in 250 mL of water, adding 77 mL of 0.2 N sodium hydroxide and 500 mL of water, adjusting with 2 N sodium hydroxide or 2 N hydrochloric acid to a pH 6.8, and diluting with water to 1000 mL), pH 6.8; 1000 mL Apparatus 1: 100 rpm for Tablets labeled to contain 750 mg Apparatus 2: 100 rpm for Tablets labeled to contain 500 mg Times: 1, 3, and 10 h Standard solution: L/100,000 mg/mL of USP Metformin Hydrochloride RS in Medium, where L is the Tablet label claim in mg. This solution is stable for 72 h at room temperature. Sample solution: At the times specified, withdraw 10 mL of the solution under test and replace with 10 mL of Medium previously equilibrated at 37.0 ± 0.5. Centrifuge at 2500 rpm for 10 min. Dilute a portion of the supernatant with Medium to obtain a theoretical concentration of L/100,000 mg/mL, where L is the Tablet label claim in mg. Detector: UV 233 nm Path length: 1 cm Blank: Medium Analysis: Calculate the concentration (mg/mL) of metformin hydrochloride (Ci) at each time point: Ci = (AU/AS) × CS AU = = absorbance of the Sample solution AS = = absorbance of the Standard solution CS = = concentration of the Standard solution (mg/mL) Calculate the cumulative percentage of metformin hydrochloride dissolved (Qi) at each time point (i): At i = 1: Q1 = (C1 × V/L) × 100 At i = 3: Q3 = [C3(V VS) + (C1 × VS)] × 100/L At i = 10: Q10 = [C10(V 2VS) + (C1 + C3)VS] × 100/L V = = initial volume of Medium, 1000 mL VS = = sampling volume, 10 mL L = = label claim (mg/Tablet) Tolerances: The percentages of the labeled amount of C4H11N5·HCl dissolved at the times specified conform to Acceptance Table 2. Time (h) Amount Dissolved 1 25%–45% 3 50%–70% 10 NLT 85% • Uniformity of Dosage Units 905: Meet the requirements IMPURITIES Organic Impurities • Procedure Mobile phase, Sample solution, and Chromatographic system: Prepare as directed in Assay. Analysis: From the chromatogram of the Sample solution obtained in Assay, calculate the percentage of each impurity in portion of Tablets taken: Result = (rU/rT) × 100 rU = = peak response for each impurity rT = = sum of all the peak responses Acceptance criteria Individual impurities: NMT 0.1% Total impurities: NMT 0.6% [Note—Disregard any peak less than 0.05%, and disregard any peak observed in blank. ] ADDITIONAL REQUIREMENTS • Packaging and Storage: Preserve in well-closed, light-resistant containers, and store at controlled room temperature. • Labeling: When more than one dissolution test is given, the labeling states the Dissolution Test used only if Test 1 is not used. • USP Reference Standards 11 USP Metformin Hydrochloride RS USP Metformin Related Compound B RS 1-Methylbiguanide. C3H9N5 115.14 USP Metformin Related Compound C RS Dimethylmelamine, or N,N-dimethyl-[1,3,5]triazine-2,4,6-triamine. C5H10N6 154.17 Auxiliary Information— Please check for your question in the FAQs before contacting USP. Topic/Question Contact Expert Committee Monograph Elena Gonikberg, Ph.D. Principal Scientific Liaison 1-301-816-8251 (SM32010) Monographs - Small Molecules 3 711 Margareth R.C. Marques, Ph.D. Senior Scientific Liaison 1-301-816-8106 (GCDF2010) General Chapters - Dosage Forms Reference Standards RS Technical Services 1-301-816-8129 rstech@usp.org USP34–NF29 Page 3443 Pharmacopeial Forum: Volume No. 35(1) Page 76 |
5樓2014-11-15 09:44:05
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