﻿{"id":31099,"date":"2025-11-12T17:18:07","date_gmt":"2025-11-12T10:18:07","guid":{"rendered":"https:\/\/nhathuocngocanh.com\/bp\/?p=31099"},"modified":"2025-11-12T17:57:20","modified_gmt":"2025-11-12T10:57:20","slug":"vigabatrin","status":"publish","type":"post","link":"https:\/\/nhathuocngocanh.com\/bp\/vigabatrin\/","title":{"rendered":"Vigabatrin"},"content":{"rendered":"<p>Edition: BP 2025 (Ph. Eur. 11.6 update)<\/p>\n<p><strong>Action and use<\/strong><\/p>\n<p>Antiepileptic.<\/p>\n<p><strong>Preparations <\/strong><\/p>\n<p>Vigabatrin Oral Powder<\/p>\n<p>Vigabatrin Tablets<\/p>\n<h2>DEFINITION<\/h2>\n<p>(4RS)-4-Aminohex-5-enoic acid.<\/p>\n<p><strong>Content<\/strong><\/p>\n<p>98.5 per cent to 101.5 per cent (anhydrous substance).<\/p>\n<h2>CHARACTERS<\/h2>\n<h3>Appearance<\/h3>\n<p>White or almost white powder.<\/p>\n<h3>Solubility<\/h3>\n<p>Freely soluble in water, slightly soluble in methanol, practically insoluble in methylene chloride.<\/p>\n<h2>IDENTIFICATION<\/h2>\n<p>Infrared absorption spectrophotometry (2.2.24).<\/p>\n<p>Comparison\u00a0 vigabatrin CRS.<\/p>\n<h2>TESTS<\/h2>\n<h3>Related substances<\/h3>\n<p>Liquid chromatography (2.2.29).<\/p>\n<p>Test solution\u00a0 Dissolve 50.0 mg of the substance to be examined in water R, using sonication if necessary, and dilute to 5.0 mL with the same solvent.<\/p>\n<p>Reference solution (a)\u00a0 Dilute 1.0 mL of the test solution to 100.0 mL with water R.<\/p>\n<p>Reference solution (b)\u00a0 Dissolve 7.5 mg of vigabatrin impurity A CRS and 7.5 mg of vigabatrin impurity B CRS in water R and dilute to 50.0 mL with the same solvent.<\/p>\n<p>Dilute 2.0 mL of the solution to 20.0 mL with water R.<\/p>\n<p>Reference solution (c)\u00a0 Dissolve 5.0 mg of vigabatrin impurity E CRS and 10.0 mg of vigabatrin impurity D CRS in water R and dilute to 50.0 mL with the same solvent. To 2.0 mL of the solution add 1.0 mL of reference solution (a) and dilute to 20.0 mL with water R.<\/p>\n<p>Reference solution (d) Dilute 2 mL of reference solution (b) to 10 mL with water R. Column:<\/p>\n<p>\u2014 size: l = 0.10 m, \u00d8 = 4.6 mm;<\/p>\n<p>\u2014 stationary phase: end-capped solid core phenylhexylsilyl silica gel for chromatography R (2.7 \u00b5m);<\/p>\n<p>\u2014 temperature: 45 \u00b0C.<\/p>\n<p>Mobile phase Dissolve 2.1 g of perfluoroheptanoic acid R in a mixture of 195 mL of methanol R2 and 805 mL of water for chromatography R.<\/p>\n<p>Flow rate\u00a0 1.0 mL\/min.<\/p>\n<p>Post-column solution methanol R2. Post-column flow rate 0.8 mL\/min.<\/p>\n<p>Detection Charged aerosol detector (gas source: nitrogen at 35 psi) and, for impurities A and B, spectrophotometer at 210 nm.<\/p>\n<p>Autosampler\u00a0 Set at 15 \u00b0C.<\/p>\n<p>Injection\u00a0 30 \u00b5L of the test solution and reference solutions (b), (c) and (d).<\/p>\n<p>Run time\u00a0 3 times the retention time of vigabatrin.<\/p>\n<p>Identification of impurities Use the chromatogram obtained with the spectrophotometer and with reference solution (b) to identify the peaks due to impurities A and B; use the chromatogram obtained with the charged aerosol detector and with reference solution (c) to identify the peaks due to impurities D and E.<\/p>\n<p>Relative retention With reference to vigabatrin (retention time = about 11 min): impurity A = about 0.3; impurity E = about 0.5; impurity D = about 0.6; impurity B = about 2.3.<\/p>\n<p>System suitability:<\/p>\n<p>\u2014 resolution: minimum 1.5 between the peaks due to impurities E and D in the chromatogram obtained with reference solution (c);<\/p>\n<p>\u2014 signal-to-noise ratio: minimum 15 for the peak due to vigabatrin in the chromatogram obtained with reference solution (c); minimum 10 for the peak due to impurity B in the chromatogram obtained with reference solution (d);<\/p>\n<p>\u2014 symmetry factor: minimum 0.6 for the peaks due to impurity D and vigabatrin in the chromatogram obtained with reference solution (c); minimum 0.6 for the peaks due to impurities A and B in the chromatogram obtained with reference solution (b).<\/p>\n<p>Calculation of percentage contents:<\/p>\n<p>\u2014 for impurities A and B, use the concentration of each impurity in reference solution (b);<\/p>\n<p>\u2014 for impurity D, use the concentration of impurity D in reference solution (c);<\/p>\n<p>\u2014 for impurities other than A, B and D, use the concentration of vigabatrin in reference solution (c).<\/p>\n<p>Limits:<\/p>\n<p>\u2014 impurity D: maximum 0.2 per cent;<\/p>\n<p>\u2014 impurities A, B (spectrophotometer at 210 nm): for each impurity, maximum 0.15 per cent;<\/p>\n<p>\u2014 unspecified impurities: for each impurity, maximum 0.05 per cent;<\/p>\n<p>\u2014 total: maximum 0.5 per cent;<\/p>\n<p>\u2014 reporting threshold: 0.03 per cent.<\/p>\n<h4>Water (2.5.12)<\/h4>\n<p>Maximum 0.5 per cent, determined on 0.300 g.<\/p>\n<h4>Sulfated ash (2.4.14)<\/h4>\n<p>Maximum 0.1 per cent, determined on 1.0 g.<\/p>\n<h2>ASSAY<\/h2>\n<p>Dissolve 90 mg in 50 mL of glacial acetic acid R. Titrate with 0.1 M perchloric acid, determining the end-point potentiometrically (2.2.20).<\/p>\n<p>1 mL of 0.1 M perchloric acid is equivalent to 12.92 mg of C<sub>6<\/sub>H<sub>11<\/sub>NO<sub>2<\/sub>.<\/p>\n<h2>IMPURITIES<\/h2>\n<p><em>Specified impurities\u00a0 A, B, D.<\/em><\/p>\n<p><em>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. It is therefore not necessary to identify these impurities for demonstration of compliance. See also 5.10. Control of impurities in substances for pharmaceutical use) E.<\/em><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-31180\" src=\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-1.jpg\" alt=\"Vigabatrin\" width=\"1200\" height=\"650\" srcset=\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-1.jpg 1200w, https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-1-300x163.jpg 300w, https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-1-1024x555.jpg 1024w, https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-1-768x416.jpg 768w\" sizes=\"auto, (max-width: 1200px) 100vw, 1200px\" \/><\/p>\n<p>A. (5RS)-5-ethenylpyrrolidin-2-one,<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-31181\" src=\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-2.jpg\" alt=\"Vigabatrin\" width=\"1200\" height=\"650\" srcset=\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-2.jpg 1200w, https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-2-300x163.jpg 300w, https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-2-1024x555.jpg 1024w, https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-2-768x416.jpg 768w\" sizes=\"auto, (max-width: 1200px) 100vw, 1200px\" \/><\/p>\n<p>B. (2E)-2-(2-aminoethyl)but-2-enoic acid,<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-31182\" src=\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-3.jpg\" alt=\"Vigabatrin\" width=\"1200\" height=\"650\" srcset=\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-3.jpg 1200w, https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-3-300x163.jpg 300w, https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-3-1024x555.jpg 1024w, https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-3-768x416.jpg 768w\" sizes=\"auto, (max-width: 1200px) 100vw, 1200px\" \/><\/p>\n<p>D. 4-aminobutanoic acid (GABA),<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-31183\" src=\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-4.jpg\" alt=\"Vigabatrin\" width=\"1200\" height=\"650\" srcset=\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-4.jpg 1200w, https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-4-300x163.jpg 300w, https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-4-1024x555.jpg 1024w, https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Vigabatrin-British-Pharmacopoeia-2025-4-768x416.jpg 768w\" sizes=\"auto, (max-width: 1200px) 100vw, 1200px\" \/><\/p>\n<p>E. 2-[(2RS)-2-aminobut-3-en-1-yl]propanedioic acid.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Edition: BP 2025 (Ph. Eur. 11.6 update) Action and use Antiepileptic. Preparations Vigabatrin Oral Powder Vigabatrin Tablets DEFINITION (4RS)-4-Aminohex-5-enoic acid. Content 98.5 per cent to 101.5 per cent (anhydrous substance). CHARACTERS Appearance White or almost white powder. Solubility Freely soluble in water, slightly soluble in methanol, practically insoluble in methylene chloride. IDENTIFICATION Infrared absorption spectrophotometry&#8230;<\/p>\n","protected":false},"author":5,"featured_media":31101,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-31099","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\/31099","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=31099"}],"version-history":[{"count":4,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/31099\/revisions"}],"predecessor-version":[{"id":31184,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/31099\/revisions\/31184"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/31101"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=31099"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=31099"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=31099"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}