{"id":26539,"date":"2025-11-05T17:25:46","date_gmt":"2025-11-05T10:25:46","guid":{"rendered":"https:\/\/nhathuocngocanh.com\/bp\/?p=26539"},"modified":"2025-11-06T17:23:19","modified_gmt":"2025-11-06T10:23:19","slug":"omeprazole-magnesium","status":"publish","type":"post","link":"https:\/\/nhathuocngocanh.com\/bp\/omeprazole-magnesium\/","title":{"rendered":"Omeprazole Magnesium"},"content":{"rendered":"

Edition: BP 2025 (Ph. Eur. 11.6 update)<\/p>\n

Action and use<\/p>\n

Proton pump inhibitor; treatment of peptic ulcer disease. Ph Eur<\/p>\n

DEFINITION<\/h2>\n

Magnesium bis[5-methoxy-2-[(RS)-[(4-methoxy-3,5-dimethylpyridin-2-yl)methyl]sulfinyl]-1H-benzimidazol-1- ide]. It contains a variable quantity of water.<\/p>\n

Content<\/strong><\/p>\n

97.5 per cent to 102.0 per cent (anhydrous substance).<\/p>\n

CHARACTERS<\/h2>\n

Appearance<\/h3>\n

White or almost white, hygroscopic powder.<\/p>\n

Solubility<\/h3>\n

Very slightly soluble in water, sparingly soluble in methanol, practically insoluble in heptane.<\/p>\n

IDENTIFICATION<\/h2>\n

Carry out either tests A, B, C or tests A, B, D.<\/p>\n

A. Optical rotation (2.2.7): -0.10\u00b0 to + 0.10\u00b0.<\/p>\n

Dissolve 0.250 g in methanol R and dilute to 25.0 mL with the same solvent.<\/p>\n

B. Infrared absorption spectrophotometry (2.2.24).<\/p>\n

Comparison\u00a0 omeprazole magnesium CRS.<\/p>\n

C. Atomic absorption spectrometry (2.2.23) as described in the test for magnesium. The test solution shows the absorption maximum at 285.2 nm.<\/p>\n

D. Ignite about 0.5 g of the substance to be examined according to the procedure for the sulfated ash test (2.4.14). Dissolve the residue in 10 mL of water R. 2 mL of this solution gives the reaction of magnesium (2.3.1).<\/p>\n

TESTS<\/h2>\n

Absorbance (2.2.25)<\/p>\n

Maximum 0.10 at 440 nm.<\/p>\n

Dissolve 0.500 g in methanol R and dilute to 25.0 mL with the same solvent. Filter the solution through a membrane filter (nominal pore size 0.45 \u00b5m).<\/p>\n

Related substances<\/h3>\n

Liquid chromatography (2.2.29): use the normalisation procedure. Prepare the solutions immediately before use.<\/p>\n

Test solution\u00a0 Dissolve 3.5 mg of the substance to be examined in the mobile phase and dilute to 25.0 mL with the mobile phase.<\/p>\n

Reference solution (a)\u00a0 Dissolve 1 mg of omeprazole CRS and 1 mg of omeprazole impurity D CRS in the mobile phase and dilute to 10.0 mL with the mobile phase.<\/p>\n

Reference solution (b)\u00a0 Dissolve 3 mg of omeprazole for peak identification CRS (containing impurity E) in the mobile phase and dilute to 20.0 mL with the mobile phase.<\/p>\n

Reference solution (c)\u00a0 Dilute 1.0 mL of the test solution to 100.0 mL with the mobile phase. Dilute 1.0 mL of this solution to 10.0 mL with the mobile phase.<\/p>\n

Column:<\/p>\n

\u2014 size: l = 0.125 m, \u00d8 = 4.6 mm;<\/p>\n

\u2014 stationary phase: octylsilyl silica gel for chromatography R (5 \u00b5m).<\/p>\n

Mobile phase\u00a0 Mix 27 volumes of acetonitrile R and 73 volumes of a 1.4 g\/L solution of disodium hydrogen phosphate dodecahydrate R previously adjusted to pH 7.6 with phosphoric acid R.<\/p>\n

Flow rate\u00a0 1 mL\/min.<\/p>\n

Detection\u00a0 Spectrophotometer at 280 nm.<\/p>\n

Injection\u00a0 40 \u00b5L.<\/p>\n

Run time\u00a0 5 times the retention time of omeprazole.<\/p>\n

Identification of impurities:<\/p>\n

\u2014 use the chromatogram supplied with omeprazole for peak identification CRS and the chromatogram obtained with reference solution (b) to identify the peak due to impurity E;<\/p>\n

\u2014 use the chromatogram obtained with reference solution (a) to identify the peak due to impurity D.<\/p>\n

Relative retention\u00a0 With reference to omeprazole (retention time = about 9 min): impurity E = about 0.6, impurity D = about 0.8.<\/p>\n

System suitability\u00a0 Reference solution (a):<\/p>\n

\u2014 resolution: minimum 3.0 between the peaks due to impurity D and omeprazole; if necessary, adjust the pH of the aqueous part of the mobile phase or its proportion of acetonitrile; an increase in the pH will improve the resolution.<\/p>\n

Limits:<\/p>\n

\u2014 impurities D, E: for each impurity, maximum 0.1 per cent;<\/p>\n

\u2014 unspecified impurities: for each impurity, maximum 0.10 per cent;<\/p>\n

\u2014 total: maximum 0.5 per cent;<\/p>\n

\u2014 disregard limit: half the area of the principal peak in the chromatogram obtained with reference solution (c) (0.05 per cent).<\/p>\n

Magnesium<\/h3>\n

3.30 per cent to 3.55 per cent (anhydrous substance).<\/p>\n

Atomic absorption spectrometry (2.2.23, Method I).<\/p>\n

Test solution\u00a0 Dissolve 0.250 g in 20.0 mL of a 103 g\/L solution of hydrochloric acid R by slow addition of the acid and dilute to 100.0 mL with water R. Dilute 10.0 mL of the solution to 200.0 mL with water R. To 10.0 mL of this solution add 4 mL of lanthanum chloride solution R and dilute to 100.0 mL with water R.<\/p>\n

Reference solutions\u00a0 Prepare the reference solutions using magnesium standard solution (1000 ppm Mg) R, diluting with a mixture of 1 mL of a 103 g\/L solution of hydrochloric acid R and 1000.0 mL of water R. Wavelength 285.2 nm.<\/p>\n

Water (2.5.12)<\/strong><\/p>\n

7.0 per cent to 10.0 per cent, determined on 0.200 g.<\/p>\n

ASSAY<\/h2>\n

Liquid chromatography (2.2.29).<\/p>\n

Buffer pH 11.0\u00a0 Mix 11 mL of a 95.0 g\/L solution of trisodium phosphate dodecahydrate R and 22 mL of a 179.1 g\/L solution of disodium hydrogen phosphate dodecahydrate R. Dilute to 100.0 mL with water R.<\/p>\n

Test solution\u00a0 Dissolve 10.0 mg of the substance to be examined in about 10 mL of methanol R. Add 10 mL of buffer pH 11.0 and dilute to 200.0 mL with water R.<\/p>\n

Reference solution\u00a0 Dissolve 10.0 mg of omeprazole CRS in about 10 mL of methanol R. Add 10 mL of buffer pH 11.0 and dilute to 200.0 mL with water R.<\/p>\n

Column:<\/p>\n

\u2014 size: l = 0.125 m, \u00d8 = 4 mm;<\/p>\n

\u2014 stationary phase: octylsilyl silica gel for chromatography R (5 \u00b5m).<\/p>\n

Mobile phase\u00a0 Mix 35 volumes of acetonitrile R and 65 volumes of a 1.4 g\/L solution of disodium hydrogen phosphate dodecahydrate R previously adjusted to pH 7.6 with phosphoric acid R.<\/p>\n

Flow rate\u00a0 1 mL\/min.<\/p>\n

Detection\u00a0 Spectrophotometer at 280 nm.<\/p>\n

Injection\u00a0 20 \u00b5L.<\/p>\n

Run time\u00a0 1.5 times the retention time of omeprazole.<\/p>\n

Retention time\u00a0 Omeprazole = about 4 min.<\/p>\n

Calculate the percentage content of C34<\/sub>H36<\/sub>MgN6<\/sub>O6<\/sub>S2<\/sub> from the declared content of omeprazole CRS. 1 g of omeprazole is equivalent to 1.032 g of omeprazole magnesium.<\/p>\n

STORAGE<\/h2>\n

In an airtight container, protected from light.<\/p>\n

IMPURITIES<\/h2>\n

Specified impurities\u00a0 D, E.<\/em><\/p>\n

Other detectable impurities (the following substances would, if present at a sufficient level, be detected by one or other of the tests in the monograph. They are limited by the general acceptance criterion for other\/unspecified impurities and\/or by the general monograph Substances for pharmaceutical use (2034). It is therefore not necessary to identify these impurities for demonstration of compliance. See also 5.10.<\/em>
\nC<\/em>ontrol of impurities in substances for pharmaceutical use)\u00a0 A, B, C.<\/em><\/p>\n

\"Omeprazole<\/p>\n

A. 5-methoxy-1H-benzimidazole-2-thiol,<\/p>\n

\"Omeprazole<\/p>\n

B. 2-[(RS)-[(3,5-dimethylpyridin-2-yl)methyl]sulfinyl]-5-methoxy-1H-benzimidazole,<\/p>\n

\"Omeprazole<\/p>\n

C. 5-methoxy-2-[[(4-methoxy-3,5-dimethylpyridin-2-yl)methyl]sulfanyl]-1H-benzimidazole,<\/p>\n

\"Omeprazole<\/p>\n

D. 5-methoxy-2-[[(4-methoxy-3,5-dimethylpyridin-2-yl)methyl]sulfonyl]-1H-benzimidazole,<\/p>\n

\"Omeprazole<\/p>\n

E. 4-methoxy-2-[[(RS)-(5-methoxy-1H-benzimidazol-2-yl)sulfinyl]methyl]-3,5-dimethylpyridine\u00a0 1-oxide.<\/p>\n

\n

Ph Eur<\/p>\n","protected":false},"excerpt":{"rendered":"

Edition: BP 2025 (Ph. Eur. 11.6 update) Action and use Proton pump inhibitor; treatment of peptic ulcer disease. Ph Eur DEFINITION Magnesium bis[5-methoxy-2-[(RS)-[(4-methoxy-3,5-dimethylpyridin-2-yl)methyl]sulfinyl]-1H-benzimidazol-1- ide]. It contains a variable quantity of water. Content 97.5 per cent to 102.0 per cent (anhydrous substance). CHARACTERS Appearance White or almost white, hygroscopic powder. Solubility Very slightly soluble in water,…<\/p>\n","protected":false},"author":5,"featured_media":26540,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-26539","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-medicinal-substances"],"acf":[],"_links":{"self":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/26539","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/comments?post=26539"}],"version-history":[{"count":3,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/26539\/revisions"}],"predecessor-version":[{"id":27316,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/26539\/revisions\/27316"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/26540"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=26539"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=26539"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=26539"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}