Anticholinergic.<\/p>\n
Ph Eur<\/p>\n
\n
DEFINITION<\/h2>\n
(RS)-N,N-Dimethyl-2-[(2-methylphenyl)phenylmethoxy]ethanamine dihydrogen 2-hydroxypropane-1,2,3- tricarboxylate.<\/p>\n
Content<\/strong><\/p>\n 98.5 per cent to 101.0 per cent (dried substance).<\/p>\n White or almost white, crystalline powder.<\/p>\n Sparingly soluble in water, slightly soluble in ethanol (96 per cent).<\/p>\n About 137 \u00b0C.<\/p>\n Infrared absorption spectrophotometry (2.2.24).<\/p>\n Comparison\u00a0 orphenadrine citrate CRS.<\/p>\n The solution is clear (2.2.1) and its absorbance (2.2.25) at 436 nm has a maximum of 0.050.<\/p>\n Dissolve 1.0 g in a 3.6 per cent V\/V solution of hydrochloric acid R in ethanol (96 per cent) R and dilute to 10.0 mL with the same acid solution.<\/p>\n Gas chromatography (2.2.28): use the normalisation procedure.<\/p>\n Test solution\u00a0 Dissolve 0.500 g of the substance to be examined in water R and dilute to 50 mL with the same solvent. Add 2 mL of concentrated ammonia R and shake with 3 quantities, each of 10 mL, of toluene R. To the combined upper layers add anhydrous sodium sulfate R, shake, filter and evaporate the filtrate by suitable means, at a temperature not exceeding 50 \u00b0C. Take up the residue with toluene R and dilute to 20.0 mL with the same solvent.<\/p>\n Reference solution (a)\u00a0 Dissolve 30 mg of orphenadrine citrate CRS and 30 mg of orphenadrine impurity E CRS in 20 mL of water R. Add 1 mL of concentrated ammonia R and shake with 3 quantities, each of 5 mL, of toluene R. To the combined upper layers add anhydrous sodium sulfate R, shake, filter and evaporate the filtrate by suitable means, at a temperature not exceeding 50 \u00b0C. Take up the residue with toluene R and dilute to 20.0 mL with the same solvent.<\/p>\n Reference solution (b)\u00a0 Dissolve the contents of a vial of orphenadrine for peak identification CRS (containing impurities A, B, C, D and F) in 1.0 mL of toluene R.<\/p>\n Column:<\/p>\n \u2014 size: l = 60 m, \u00d8 = 0.32 mm;<\/p>\n \u2014 stationary phase: phenyl(5)methyl(95)polysiloxane R (film thickness 1.0 \u00b5m).<\/p>\n Carrier gas helium for chromatography R. Flow rate 1 mL\/min.<\/p>\n Split ratio\u00a0 1:25.<\/p>\n Temperature:<\/p>\n \u2014 column: 240 \u00b0C;<\/p>\n \u2014 injection port and detector: 290 \u00b0C.<\/p>\n Detection\u00a0 Flame ionisation.<\/p>\n Injection\u00a0 2 \u00b5L.<\/p>\n Run time\u00a0 1.3 times the retention time of orphenadrine.<\/p>\n Identification of impurities\u00a0 Use the chromatogram supplied with orphenadrine for peak identification CRS and the chromatogram obtained with reference solution (b) to identify the peaks due to impurities A, B, C, D and F. Use the chromatogram obtained with reference solution (a) to identify the peak due to impurity E.<\/p>\n Relative retention\u00a0 With reference to orphenadrine (retention time = about 13 min): impurity B = about 0.5; impurity A = about 0.6; impurity D = about 0.8; impurity C = about 0.9; impurity E = about 0.98; impurity F = about 1.1.<\/p>\n System suitability\u00a0 Reference solution (a):<\/p>\n \u2014 resolution: minimum of 1.5 between the peaks due to impurity E and orphenadrine.<\/p>\n Limits:<\/p>\n \u2014 impurities A, B, C, D, E, F: for each impurity, not more than 0.3 per cent;<\/p>\n \u2014 unspecified impurities: for each impurity, not more than 0.10 per cent;<\/p>\n \u2014 total: maximum 1.0 per cent;<\/p>\n \u2014 disregard limit: 0.05 per cent.<\/p>\n Loss on drying (2.2.32)<\/strong><\/p>\n Maximum 0.5 per cent, determined on 1.000 g by drying in an oven at 105 \u00b0C for 3 h.<\/p>\n Sulfated ash (2.4.14)<\/strong><\/p>\n Maximum 0.1 per cent, determined on 1.0 g.<\/p>\n Dissolve 0.350 g in 50 mL of anhydrous acetic acid R. Titrate with 0.1 M perchloric acid, determining the end-point potentiometrically (2.2.20).<\/p>\n 1 mL of 0.1 M perchloric acid is equivalent to 46.15 mg of C24H31NO8.<\/p>\n Protected from light. If the substance is sterile, store in a sterile, airtight, tamper-evident container, protected from light.<\/p>\n Specified impurities\u00a0 A, B, C, D, E, F.<\/p>\n A. (RS)-(2-methylphenyl)phenylmethanol (2-methylbenzhydrol),<\/p>\n B. (2-methylphenyl)phenylmethanone (2-methylbenzophenone),<\/p>\n C. (RS)-2-[(2-methylphenyl)phenylmethoxy]ethanamine,<\/p>\n D. 2-(diphenylmethoxy)-N,N-dimethylethanamine (diphenhydramine),<\/p>\n E. (RS)-N,N-dimethyl-2-[(3-methylphenyl)phenylmethoxy]ethanamine (meta-methylbenzyl isomer),<\/p>\n F. (RS)-N,N-dimethyl-2-[(4-methylphenyl)phenylmethoxy]ethanamine (para-methylbenzyl isomer).<\/p>\n Ph Eur<\/p>\n","protected":false},"excerpt":{"rendered":" Edition: BP 2025 (Ph. Eur. 11.6 update) Action and use Anticholinergic. Ph Eur DEFINITION (RS)-N,N-Dimethyl-2-[(2-methylphenyl)phenylmethoxy]ethanamine dihydrogen 2-hydroxypropane-1,2,3- tricarboxylate. Content 98.5 per cent to 101.0 per cent (dried substance). CHARACTERS Appearance White or almost white, crystalline powder. Solubility Sparingly soluble in water, slightly soluble in ethanol (96 per cent). mp About 137 \u00b0C. IDENTIFICATION Infrared absorption…<\/p>\n","protected":false},"author":5,"featured_media":26604,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-26603","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\/26603","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=26603"}],"version-history":[{"count":5,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/26603\/revisions"}],"predecessor-version":[{"id":32275,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/26603\/revisions\/32275"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/26604"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=26603"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=26603"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=26603"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}CHARACTERS<\/h2>\n
Appearance<\/h3>\n
Solubility<\/h3>\n
mp<\/h3>\n
IDENTIFICATION<\/h2>\n
TESTS<\/h2>\n
Appearance of solution<\/h3>\n
Related substances<\/h3>\n
ASSAY<\/h2>\n
STORAGE<\/h2>\n
IMPURITIES<\/h2>\n
![\"Orphenadrine](\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Orphenadrine-Citrate-British-Pharmacopoeia-2025-1.jpg\")
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