﻿{"id":28781,"date":"2025-11-08T17:39:37","date_gmt":"2025-11-08T10:39:37","guid":{"rendered":"https:\/\/nhathuocngocanh.com\/bp\/?p=28781"},"modified":"2025-11-08T17:39:37","modified_gmt":"2025-11-08T10:39:37","slug":"quinine-dihydrochloride","status":"publish","type":"post","link":"https:\/\/nhathuocngocanh.com\/bp\/quinine-dihydrochloride\/","title":{"rendered":"Quinine Dihydrochloride"},"content":{"rendered":"<p>Edition: BP 2025 (Ph. Eur. 11.6 update)<\/p>\n<p><strong>Action and use<\/strong><\/p>\n<p>Antiprotozoal (malaria).<\/p>\n<p><strong>Preparation<\/strong><\/p>\n<p>Quinine Dihydrochloride Infusion<\/p>\n<h2>DEFINITION<\/h2>\n<p>Quinine Dihydrochloride is (8S,9R)-6\u2032-methoxycinchonan-9-ol dihydrochloride. It contains not less than 99.0% and not more than 101.0% of alkaloid dihydrochlorides, calculated as C<sub>20<\/sub>H<sub>24<\/sub>N<sub>2<\/sub>O<sub>2<\/sub>,2HCl, with reference to the dried substance.<\/p>\n<h2>CHARACTERISTICS<\/h2>\n<p>A white or almost white powder.<\/p>\n<p>Very soluble in water; soluble in ethanol (96%).<\/p>\n<h2>IDENTIFICATION<\/h2>\n<p>A. Carry out the method for thin-layer chromatography (2.2.27), Appendix III A, using the following solutions in methanol.<\/p>\n<p>(1) 1.0% w\/v of the substance being examined.<\/p>\n<p>(2) 1.0% w\/v of quinine sulfate BPCRS.<\/p>\n<p>(3) 1.0% w\/v each of quinidine sulfate BPCRS and quinine sulfate BPCRS.<\/p>\n<h3>CHROMATOGRAPHIC CONDITIONS<\/h3>\n<p>(a) Use as the coating silica gel G.<\/p>\n<p>(b) Use the mobile phase as described below.<\/p>\n<p>(c) Apply 4 \u00b5L of each solution.<\/p>\n<p>(d) Develop the plate to 15 cm.<\/p>\n<p>(e) After removal of the plate, dry it in a current of air for 15 minutes and repeat the development. Dry the plate at 105\u00b0 for 30 minutes, allow to cool and spray with iodoplatinate reagent.<\/p>\n<h3>MOBILE PHASE<\/h3>\n<p>15 volumes of diethylamine, 36 volumes of ether and 60 volumes of toluene.<\/p>\n<h3>SYSTEM SUITABILITY<\/h3>\n<p>The test is not valid unless the chromatogram obtained with solution (3) shows two clearly separated spots.<\/p>\n<h3>CONFIRMATION<\/h3>\n<p>The principal spot in the chromatogram obtained with solution (1) corresponds in position, colour and size to that in the chromatogram obtained with solution (2).<\/p>\n<p>B. Complies with the test for Acidity.<\/p>\n<p>C. Yields reaction A characteristic of chlorides, (2.3.1) Appendix VI.<\/p>\n<h2>TESTS<\/h2>\n<h3>Acidity<\/h3>\n<p>pH of a 3% w\/v solution, 2.0 to 3.0, Appendix V L.<\/p>\n<p><strong>Specific optical rotation (2.2.7)<\/strong><\/p>\n<p>In a 3% w\/v solution in 0.1M hydrochloric acid, -223 to -229 calculated with reference to the dried substance, Appendix V F.<\/p>\n<h3>Barium<\/h3>\n<p>To 15 mL of a 2.0% w\/v solution add 1 mL of 1M sulfuric acid. The solution remains clear for at least 15 minutes.<\/p>\n<p><strong>Sulfate (2.4.13)<\/strong><\/p>\n<p>0.125 g complies with the limit test for sulfates, Appendix VII (0.12%).<\/p>\n<h3>Other cinchona alkaloids<\/h3>\n<p>Carry out the method for liquid chromatography (2.2.29) Appendix III D, using the normalisation procedure and the following solutions in the mobile phase.<\/p>\n<p>(1) Dissolve 20 mg of the substance being examined, with gentle heating if necessary, in 5 mL and dilute to 10 mL.<\/p>\n<p>(2) Prepare as for solution (1) but using quinine sulfate BPCRS in place of the substance being examined.<\/p>\n<p>(3) Prepare as for solution (1) but using quinidine sulfate BPCRS in place of the substance being examined.<\/p>\n<p>(4) Mix equal volumes of solutions (2) and (3).<\/p>\n<p>(5) Dilute 1 volume of solution (2) to 10 volumes and dilute 1 volume of the resulting solution to 50 volumes.<\/p>\n<p>(6) 0.10% w\/v of thiourea.<\/p>\n<h4>CHROMATOGRAPHIC CONDITIONS<\/h4>\n<p>(a) Use a stainless steel column (25 cm \u00d7 4.6 mm) packed with octadecylsilyl silica gel for chromatography (5 \u00b5m) (Hypersil ODS 5 \u00b5m is suitable).<\/p>\n<p>(b) Use isocratic elution and the mobile phase described below.<\/p>\n<p>(c) Use a flow rate of 1.5 mL per minute.<\/p>\n<p>(d) Use an ambient column temperature.<\/p>\n<p>(e) Use a detection wavelength of 250 nm for recording the chromatogram obtained with solution (6) and a detection wavelength of 316 nm for the other solutions.<\/p>\n<p>(f) Inject 10 \u00b5L of each solution. Inject separately 10 \u00b5L of each of solutions (3) and (6).<\/p>\n<p>(g) For solution (1) allow the chromatography to proceed for 2.5 times the retention time of the principal peak.<\/p>\n<h4>MOBILE PHASE<\/h4>\n<p>Dissolve 6.8 g of potassium dihydrogen orthophosphate and 3.0 g of hexylamine in 700 mL of water, adjust to pH 2.8 with 1M orthophosphoric acid, add 60 mL of acetonitrile and dilute to 1000 mL with water. If necessary adjust the concentration of acetonitrile in the mobile phase so that in the chromatogram obtained with solution (3) the capacity factor of the peak due to quinidine is 3.5 to 4.5, VO being calculated from the peak due to thiourea in the chromatogram obtained with<br \/>\nsolution (6).<\/p>\n<h4>SYSTEM SUITABILITY<\/h4>\n<p>The test is not valid unless (a) in the chromatogram obtained with solution (4) the resolution between the peaks due to quinine and quinidine is at least 1.5 and the resolution between the peaks due to dihydroquinidine and quinine is at least 1.0 and (b) the signal-to-noise ratio of the principal peak in the chromatogram obtained with solution (5) is at least 5.<\/p>\n<p>The chromatogram obtained with solution (2) shows a principal peak due to quinidine and a peak due to dihydroquinine with a retention time relative to quinine of about 1.4. The chromatogram obtained with solution (3) shows a principal peak due to quinidine and a peak due to dihydroquinidine, with a retention time relative to quinidine of about 1.2. The chromatogram obtained with solution (4) shows four peaks due to quinine, dihydroquinine, quinidine and dihydroquinidine which are identified by comparison of their retention times with those of the corresponding peaks in the chromatograms obtained with solutions (2) and (3).<\/p>\n<h4>LIMITS<\/h4>\n<p>In the chromatogram obtained with solution (1):<\/p>\n<p>the content of dihydroquinine is not greater than 10%;<\/p>\n<p>the content of any related substance eluting before quinine is not more than 5%; the content of any other related substance is not more than 2.5%.<\/p>\n<p>Disregard any peak with an area less than that of the peak in the chromatogram obtained with solution (5).<\/p>\n<p><strong>Loss on drying (2.2.32)<\/strong><\/p>\n<p>When dried to constant weight at 105\u00b0, loses not more than 3.0% of its weight. Use 1 g.<\/p>\n<p><strong>Sulfated ash (2.4.14)<\/strong><\/p>\n<p>Not more than 0.1%, Appendix IX A.<\/p>\n<h2>ASSAY<\/h2>\n<p>Dissolve 0.150 g in a mixture of 10 mL of water and 50 mL of ethanol. Titrate with 0.1M sodium hydroxide, determining the end-point potentiometrically, Appendix VIII B.<\/p>\n<p>Each mL of 0.1M sodium hydroxide is equivalent to 39.73 mg of C<sub>20<\/sub>H<sub>24<\/sub>N<sub>2<\/sub>O<sub>2<\/sub>,2HCl.<\/p>\n<h2>STORAGE<\/h2>\n<p>Quinine Dihydrochloride should be protected from light.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Edition: BP 2025 (Ph. Eur. 11.6 update) Action and use Antiprotozoal (malaria). Preparation Quinine Dihydrochloride Infusion DEFINITION Quinine Dihydrochloride is (8S,9R)-6\u2032-methoxycinchonan-9-ol dihydrochloride. It contains not less than 99.0% and not more than 101.0% of alkaloid dihydrochlorides, calculated as C20H24N2O2,2HCl, with reference to the dried substance. CHARACTERISTICS A white or almost white powder. Very soluble in&#8230;<\/p>\n","protected":false},"author":5,"featured_media":28782,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-28781","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\/28781","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=28781"}],"version-history":[{"count":2,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/28781\/revisions"}],"predecessor-version":[{"id":28786,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/28781\/revisions\/28786"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/28782"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=28781"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=28781"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=28781"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}