{"id":9272,"date":"2025-10-06T08:59:47","date_gmt":"2025-10-06T01:59:47","guid":{"rendered":"https:\/\/nhathuocngocanh.com\/bp\/?p=9272"},"modified":"2025-11-15T15:07:01","modified_gmt":"2025-11-15T08:07:01","slug":"dexamethasone-sodium-phosphate","status":"publish","type":"post","link":"https:\/\/nhathuocngocanh.com\/bp\/dexamethasone-sodium-phosphate\/","title":{"rendered":"Dexamethasone Sodium Phosphate"},"content":{"rendered":"

(Ph. Eur. monograph 0549)<\/p>\n

C_{22<\/sub>H_{28<\/sub>FNa_{2<\/sub>O_{8<\/sub>P\u00a0 \u00a0 516.4\u00a0 \u00a0 2392-39-4<\/p>\n}}}}

Action and use<\/strong><\/p>\n

Glucocorticoid.<\/p>\n

Preparations<\/strong><\/p>\n

Dexamethasone Sodium Phosphate Eye Drops<\/p>\n

Dexamethasone Sodium Phosphate Injection<\/p>\n

Dexamethasone Sodium Phosphate Oral Solution<\/p>\n

DEFINITION<\/h2>\n
Disodium 9-fluoro-11\u03b2,17-dihydroxy-16\u03b1-methyl-3,20-dioxopregna-1,4-dien-21-yl phosphate.<\/p>\n
Content<\/h3>\n
97.0 per cent to 102.0 per cent (anhydrous substance).<\/p>\n
CHARACTERS<\/h2>\n
Appearance<\/h3>\n
White or almost white, very hygroscopic powder.<\/p>\n
Solubility<\/h3>\n
Freely soluble in water, slightly soluble in ethanol (96 per cent), practically insoluble in methylene chloride.<\/p>\n
It shows polymorphism (5.9).<\/p>\n
IDENTIFICATION<\/h2>\n
First identification: A, D.<\/p>\n
Second identification: B, C.<\/p>\n
A. Infrared absorption spectrophotometry (2.2.24).<\/p>\n
Comparison dexamethasone sodium phosphate CRS.<\/p>\n
If the spectra obtained in the solid state show differences, dissolve the substance to be examined and the reference substance separately in the minimum volume of ethanol (96 per cent) R, evaporate to dryness on a water-bath and record new spectra using the residues.<\/p>\n
B. Thin-layer chromatography (2.2.27).<\/p>\n
Test solution: Dissolve 10 mg of the substance to be examined in methanol R and dilute to 10.0 mL with the same solvent.<\/p>\n
Reference solution: Dissolve 10 mg of dexamethasone sodium phosphate CRS in methanol R and dilute to 10.0 mL with the same solvent.<\/p>\n
Plate TLC silica gel F254 plate R.<\/p>\n
Mobile phase glacial acetic acid R, water R, butanol R (20:20:60 V\/V\/V).<\/p>\n
Application 5 \u03bcL.<\/p>\n
Development: Over 3\/4 of the plate.<\/p>\n
Drying In air.<\/p>\n
Detection: Spray with a solution prepared as follows: dissolve 0.25 g of 2,4-dihydroxybenzaldehyde R in glacial acetic acid R, dilute to 50 mL with the same solvent and add a mixture of 12.5 mL of sulfuric acid R and 37.5 mL of glacial acetic acid R; heat the plate at 90 \u00b0C for 35 min or until the spots appear and allow to cool; examine in daylight and in ultraviolet light at 365 nm.<\/p>\n
Results: The principal spot in the chromatogram obtained with the test solution is similar in position, colour and size to the principal spot in the chromatogram obtained with the reference solution.<\/p>\n
C. Add about 2 mg to 2 mL of sulfuric acid R and shake to dissolve. Within 5 min, a faint yellowish-brown colour
\ndevelops. Add the solution to 10 mL of water R and mix. The colour disappears and a clear solution remains.<\/p>\n
D. Examine the chromatograms obtained in the assay.<\/p>\n
Results: The principal peak in the chromatogram obtained with the test solution is similar in retention time and size to the principal peak in the chromatogram obtained with reference solution (b).<\/p>\n
TESTS<\/h2>\n
Solution S<\/h3>\n
Dissolve 1.0 g in carbon dioxide-free water R and dilute to 20 mL with the same solvent.<\/p>\n
Appearance of solution<\/h3>\n
Solution S is clear (2.2.1) and not more intensely coloured than reference solution B7 (2.2.2, Method II).<\/p>\n
pH (2.2.3)<\/h4>\n
7.5 to 9.5.<\/p>\n
Dilute 1 mL of solution S to 5 mL with carbon dioxide-free water R.<\/p>\n
Specific optical rotation (2.2.7)<\/h4>\n
+ 75 to + 83 (anhydrous substance).<\/p>\n
Dissolve 0.250 g in water R and dilute to 25.0 mL with the same solvent.<\/p>\n
Related substances<\/h3>\n
Liquid chromatography (2.2.29).<\/p>\n
Solution A Dissolve 7.0 g of ammonium acetate R in 1000 mL of water R.<\/p>\n
Test solution Dissolve 10 mg of the substance to be examined in mobile phase A and dilute to 10.0 mL with mobile
\nphase A.<\/p>\n
Reference solution (a) Dissolve 2 mg of betamethasone sodium phosphate CRS (impurity B) and 2 mg of
\ndexamethasone sodium phosphate CRS in mobile phase A, then dilute to 100 mL with mobile phase A.<\/p>\n
Reference solution (b) Dissolve 2 mg of dexamethasone sodium phosphate for peak identification CRS (containing
\nimpurities A, C, D, E, F and G) in mobile phase A and dilute to 2 mL with mobile phase A.<\/p>\n
Reference solution (c) Dilute 1.0 mL of the test solution to 100.0 mL with mobile phase A. Dilute 1.0 mL of this solution to 10.0 mL with mobile phase A.<\/p>\n
Column:<\/p>\n
\u2014 size: l = 0.125 m, \u00d8 = 4.6 mm;<\/p>\n
\u2014 stationary phase: end-capped octylsilyl silica gel for chromatography R (5 \u03bcm);<\/p>\n
\u2014 temperature: 30 \u00b0C.<\/p>\n
Mobile phase:<\/p>\n
\u2014 mobile phase A: mix 300 mL of solution A and 350 mL of water for chromatography R, adjust to pH 3.8 with acetic acid R, then add 350 mL of methanol R;<\/p>\n
\u2014 mobile phase B: adjust 300 mL of solution A to pH 4.0 with acetic acid R, then add 700 mL of methanol R;<\/p>\n\n\n\n\n\n\n\n
Time
\n(min)<\/td>\n Mobile phase A
\n(per cent V\/V)<\/td>\n Mobile phase B
\n(per cent V\/V)<\/td>\n<\/tr>\n
0 – 3.5<\/td>\n 90<\/td>\n 10<\/td>\n<\/tr>\n
3.5 – 23.5<\/td>\n \u00a090 \u2192 60<\/td>\n \u00a010 \u2192 40<\/td>\n<\/tr>\n
23.5 – 34.5<\/td>\n \u00a060 \u2192 5<\/td>\n \u00a040 \u2192 95<\/td>\n<\/tr>\n
34.5 – 50<\/td>\n 5<\/td>\n 95<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
Flow rate 1.0 mL\/min.<\/p>\n
Detection Spectrophotometer at 254 nm.<\/p>\n
Injection 20 \u03bcL.<\/p>\n
Identification of impurities Use the chromatogram supplied with dexamethasone sodium phosphate for peak
\nidentification CRS and the chromatogram obtained with reference solution (b) to identify the peaks due to impurities A, C, D, E, F and G; use the chromatogram obtained with reference solution (a) to identify the peak due to impurity B.<\/p>\n
Relative retention With reference to dexamethasone sodium phosphate (retention time = about 22 min):
\nimpurity C = about 0.5; impurity D = about 0.6; impurity E = about 0.8; impurity F = about 0.92; impurity B = about 0.95; impurity A = about 1.37; impurity G = about 1.41.<\/p>\n
System suitability Reference solution (a):<\/p>\n
\u2014 resolution: minimum 2.0 between the peaks due to impurity B and dexamethasone sodium phosphate.<\/p>\n
Limits:<\/p>\n
\u2014 correction factor: for the calculation of content, multiply the peak area of impurity A by 0.75;<\/p>\n
\u2014 impurity A: not more than 5 times the area of the principal peak in the chromatogram obtained with reference
\nsolution (c) (0.5 per cent);<\/p>\n
\u2014 impurity G: not more than 3 times the area of the principal peak in the chromatogram obtained with reference
\nsolution (c) (0.3 per cent);<\/p>\n
\u2014 impurities B, C, D, E, F: for each impurity, not more than twice the area of the principal peak in the chromatogram obtained with reference solution (c) (0.2 per cent);<\/p>\n
\u2014 unspecified impurities: for each impurity, not more than the area of the principal peak in the chromatogram obtained with reference solution (c) (0.10 per cent);<\/p>\n
\u2014 total: not more than 10 times the area of the principal peak in the chromatogram obtained with reference
\nsolution (c) (1.0 per cent);<\/p>\n
\u2014 disregard limit: 0.5 times the area of the principal peak in the chromatogram obtained with reference solution (c)
\n(0.05 per cent).<\/p>\n
Inorganic phosphates<\/h3>\n
Maximum 1 per cent.<\/p>\n
Dissolve 50 mg in water R and dilute to 100 mL with the same solvent. To 10 mL of the solution add 5 mL of
\nmolybdovanadic reagent R, mix and allow to stand for 5 min. Any yellow colour in the solution is not more intense than that in a standard prepared at the same time in the same manner using 10 mL of phosphate standard solution (5 ppm PO4) R.<\/p>\n
Ethanol (2.4.24, System A)<\/h3>\n
Maximum 1.5 per cent.<\/p>\n
Water (2.5.12)<\/h4>\n
Maximum 10.0 per cent, determined on 0.200 g.<\/p>\n
ASSAY<\/h2>\n
Liquid chromatography (2.2.29).<\/p>\n
Test solution: Dissolve 30.0 mg of the substance to be examined in the mobile phase and dilute to 50.0 mL with the
\nmobile phase. Dilute 5.0 mL of the solution to 50.0 mL with the mobile phase.<\/p>\n
Reference solution (a): Dissolve 2 mg of dexamethasone CRS (impurity A) and 2 mg of dexamethasone sodium
\nphosphate CRS in 2 mL of tetrahydrofuran R, then dilute to 100 mL with the mobile phase. Dilute 5 mL of this solution to 50 mL with the mobile phase.<\/p>\n
Reference solution (b): Dissolve 30.0 mg of dexamethasone sodium phosphate CRS in the mobile phase and dilute to 50.0 mL with the mobile phase. Dilute 5.0 mL of the solution to 50.0 mL with the mobile phase.<\/p>\n
Column:<\/p>\n
\u2014 size: l = 0.15 m, \u00d8 = 4.6 mm;<\/p>\n
\u2014 stationary phase: end-capped octadecylsilyl silica gel for chromatography R (7 \u03bcm).<\/p>\n
Mobile phase: Mix 520 mL of water for chromatography R with 2 mL of phosphoric acid R. Adjust the temperature to 20 \u00b0C, then adjust to pH 2.6 with sodium hydroxide R. Mix this solution with 36 mL of tetrahydrofuran R and 364 mL of methanol R.<\/p>\n
Flow rate 1.5 mL\/min.<\/p>\n
Detection Spectrophotometer at 254 nm.<\/p>\n
Injection 20 \u03bcL.<\/p>\n
Run time 3 times the retention time of dexamethasone sodium phosphate.<\/p>\n
Identification of impurities Use the chromatogram obtained with reference solution (a) to identify the peak due to
\nimpurity A.<\/p>\n
Relative retention With reference to dexamethasone sodium phosphate (retention time = about 8 min):
\nimpurity A = about 2.0.<\/p>\n
System suitability Reference solution (a):<\/p>\n
\u2014 resolution: minimum 6.0 between the peaks due to dexamethasone sodium phosphate and impurity A.<\/p>\n
Calculate the percentage content of C_{22<\/sub>H_{28<\/sub>FNa_{2<\/sub>O_{8<\/sub>P\u00a0using the chromatogram obtained with reference solution (b) and taking into account the assigned content of dexamethasone sodium phosphate CRS.<\/p>\n}}}}
STORAGE<\/h2>\n
In an airtight container, protected from light.<\/p>\n
IMPURITIES<\/h2>\n
Specified impurities A, B, C, D, E, F, G.<\/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. Control of impurities in substances for pharmaceutical use) H.<\/p>\n
$\"Dexamethasone$ <\/p>\n
A. 9-fluoro-11\u03b2,17,21-trihydroxy-16\u03b1-methylpregna-1,4-diene-3,20-dione (dexamethasone),<\/p>\n
$\"Dexamethasone$ <\/p>\n
B. 9-fluoro-11\u03b2,17-dihydroxy-16\u03b2-methyl-3,20-dioxopregna-1,4-dien-21-yl dihydrogen phosphate (betamethasone
\nphosphate),<\/p>\n
$\"Dexamethasone$ <\/p>\n
C, D, E, F. for each impurity: one or more diastereoisomer(s) of (9-fluoro-11\u03b2,17a\u03be-dihydroxy-16\u03be-methyl-3,17-dioxo-17a\u03be-homoandrosta-1,4-dien-17a\u03be-yl)methyl dihydrogen phosphate (undefined stereochemistry at C-16 and C-17a), or (9-fluoro-11\u03b2,17\u03be-dihydroxy-16\u03b1-methyl-3,17a-dioxo-17a-homoandrosta-1,4-dien-17\u03be-yl)methyl dihydrogen phosphate (undefined stereochemistry at C-17),<\/p>\n
$\"Dexamethasone$ <\/p>\n
G. 9-fluoro-11\u03b2,17\u03b1-dihydroxy-16\u03b1-methyl-3-oxoandrosta-1,4-diene-17\u03b2-carboxylic acid.<\/p>\n
$\"Dexamethasone$ <\/p>\n
H. 9-fluoro-11\u03b2,17-dihydroxy-16\u03b1-methyl-3,20-dioxopregn-4-en-21-yl dihydrogen phosphate.<\/p>\n","protected":false},"excerpt":{"rendered":"
(Ph. Eur. monograph 0549) C22H28FNa2O8P\u00a0 \u00a0 516.4\u00a0 \u00a0 2392-39-4 Action and use Glucocorticoid. Preparations Dexamethasone Sodium Phosphate Eye Drops Dexamethasone Sodium Phosphate Injection Dexamethasone Sodium Phosphate Oral Solution DEFINITION Disodium 9-fluoro-11\u03b2,17-dihydroxy-16\u03b1-methyl-3,20-dioxopregna-1,4-dien-21-yl phosphate. Content 97.0 per cent to 102.0 per cent (anhydrous substance). CHARACTERS Appearance White or almost white, very hygroscopic powder. Solubility Freely soluble in…<\/p>\n","protected":false},"author":3,"featured_media":9288,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-9272","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\/9272","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\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/comments?post=9272"}],"version-history":[{"count":2,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/9272\/revisions"}],"predecessor-version":[{"id":9291,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/9272\/revisions\/9291"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/9288"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=9272"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=9272"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=9272"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}

Time \n(min)<\/td>\n	Mobile phase A \n(per cent V\/V)<\/td>\n	Mobile phase B \n(per cent V\/V)<\/td>\n<\/tr>\n
0 – 3.5<\/td>\n	90<\/td>\n	10<\/td>\n<\/tr>\n
3.5 – 23.5<\/td>\n	\u00a090 \u2192 60<\/td>\n	\u00a010 \u2192 40<\/td>\n<\/tr>\n
23.5 – 34.5<\/td>\n	\u00a060 \u2192 5<\/td>\n	\u00a040 \u2192 95<\/td>\n<\/tr>\n
34.5 – 50<\/td>\n	5<\/td>\n	95<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Flow rate 1.0 mL\/min.<\/p>\n Detection Spectrophotometer at 254 nm.<\/p>\n Injection 20 \u03bcL.<\/p>\n Identification of impurities Use the chromatogram supplied with dexamethasone sodium phosphate for peak \nidentification CRS and the chromatogram obtained with reference solution (b) to identify the peaks due to impurities A, C, D, E, F and G; use the chromatogram obtained with reference solution (a) to identify the peak due to impurity B.<\/p>\n Relative retention With reference to dexamethasone sodium phosphate (retention time = about 22 min): \nimpurity C = about 0.5; impurity D = about 0.6; impurity E = about 0.8; impurity F = about 0.92; impurity B = about 0.95; impurity A = about 1.37; impurity G = about 1.41.<\/p>\n System suitability Reference solution (a):<\/p>\n \u2014 resolution: minimum 2.0 between the peaks due to impurity B and dexamethasone sodium phosphate.<\/p>\n Limits:<\/p>\n \u2014 correction factor: for the calculation of content, multiply the peak area of impurity A by 0.75;<\/p>\n \u2014 impurity A: not more than 5 times the area of the principal peak in the chromatogram obtained with reference \nsolution (c) (0.5 per cent);<\/p>\n \u2014 impurity G: not more than 3 times the area of the principal peak in the chromatogram obtained with reference \nsolution (c) (0.3 per cent);<\/p>\n \u2014 impurities B, C, D, E, F: for each impurity, not more than twice the area of the principal peak in the chromatogram obtained with reference solution (c) (0.2 per cent);<\/p>\n \u2014 unspecified impurities: for each impurity, not more than the area of the principal peak in the chromatogram obtained with reference solution (c) (0.10 per cent);<\/p>\n \u2014 total: not more than 10 times the area of the principal peak in the chromatogram obtained with reference \nsolution (c) (1.0 per cent);<\/p>\n \u2014 disregard limit: 0.5 times the area of the principal peak in the chromatogram obtained with reference solution (c) \n(0.05 per cent).<\/p>\n Inorganic phosphates<\/h3>\n Maximum 1 per cent.<\/p>\n Dissolve 50 mg in water R and dilute to 100 mL with the same solvent. To 10 mL of the solution add 5 mL of \nmolybdovanadic reagent R, mix and allow to stand for 5 min. Any yellow colour in the solution is not more intense than that in a standard prepared at the same time in the same manner using 10 mL of phosphate standard solution (5 ppm PO4) R.<\/p>\n Ethanol (2.4.24, System A)<\/h3>\n Maximum 1.5 per cent.<\/p>\n Water (2.5.12)<\/h4>\n Maximum 10.0 per cent, determined on 0.200 g.<\/p>\n ASSAY<\/h2>\n Liquid chromatography (2.2.29).<\/p>\n Test solution: Dissolve 30.0 mg of the substance to be examined in the mobile phase and dilute to 50.0 mL with the \nmobile phase. Dilute 5.0 mL of the solution to 50.0 mL with the mobile phase.<\/p>\n Reference solution (a): Dissolve 2 mg of dexamethasone CRS (impurity A) and 2 mg of dexamethasone sodium \nphosphate CRS in 2 mL of tetrahydrofuran R, then dilute to 100 mL with the mobile phase. Dilute 5 mL of this solution to 50 mL with the mobile phase.<\/p>\n Reference solution (b): Dissolve 30.0 mg of dexamethasone sodium phosphate CRS in the mobile phase and dilute to 50.0 mL with the mobile phase. Dilute 5.0 mL of the solution to 50.0 mL with the mobile phase.<\/p>\n Column:<\/p>\n \u2014 size: l = 0.15 m, \u00d8 = 4.6 mm;<\/p>\n \u2014 stationary phase: end-capped octadecylsilyl silica gel for chromatography R (7 \u03bcm).<\/p>\n Mobile phase: Mix 520 mL of water for chromatography R with 2 mL of phosphoric acid R. Adjust the temperature to 20 \u00b0C, then adjust to pH 2.6 with sodium hydroxide R. Mix this solution with 36 mL of tetrahydrofuran R and 364 mL of methanol R.<\/p>\n Flow rate 1.5 mL\/min.<\/p>\n Detection Spectrophotometer at 254 nm.<\/p>\n Injection 20 \u03bcL.<\/p>\n Run time 3 times the retention time of dexamethasone sodium phosphate.<\/p>\n Identification of impurities Use the chromatogram obtained with reference solution (a) to identify the peak due to \nimpurity A.<\/p>\n Relative retention With reference to dexamethasone sodium phosphate (retention time = about 8 min): \nimpurity A = about 2.0.<\/p>\n System suitability Reference solution (a):<\/p>\n \u2014 resolution: minimum 6.0 between the peaks due to dexamethasone sodium phosphate and impurity A.<\/p>\n Calculate the percentage content of C_{22<\/sub>H_{28<\/sub>FNa_{2<\/sub>O_{8<\/sub>P\u00a0using the chromatogram obtained with reference solution (b) and taking into account the assigned content of dexamethasone sodium phosphate CRS.<\/p>\n}}}} STORAGE<\/h2>\n In an airtight container, protected from light.<\/p>\n IMPURITIES<\/h2>\n Specified impurities A, B, C, D, E, F, G.<\/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. Control of impurities in substances for pharmaceutical use) H.<\/p>\n $\"Dexamethasone$ <\/p>\n A. 9-fluoro-11\u03b2,17,21-trihydroxy-16\u03b1-methylpregna-1,4-diene-3,20-dione (dexamethasone),<\/p>\n $\"Dexamethasone$ <\/p>\n B. 9-fluoro-11\u03b2,17-dihydroxy-16\u03b2-methyl-3,20-dioxopregna-1,4-dien-21-yl dihydrogen phosphate (betamethasone \nphosphate),<\/p>\n $\"Dexamethasone$ <\/p>\n C, D, E, F. for each impurity: one or more diastereoisomer(s) of (9-fluoro-11\u03b2,17a\u03be-dihydroxy-16\u03be-methyl-3,17-dioxo-17a\u03be-homoandrosta-1,4-dien-17a\u03be-yl)methyl dihydrogen phosphate (undefined stereochemistry at C-16 and C-17a), or (9-fluoro-11\u03b2,17\u03be-dihydroxy-16\u03b1-methyl-3,17a-dioxo-17a-homoandrosta-1,4-dien-17\u03be-yl)methyl dihydrogen phosphate (undefined stereochemistry at C-17),<\/p>\n $\"Dexamethasone$ <\/p>\n G. 9-fluoro-11\u03b2,17\u03b1-dihydroxy-16\u03b1-methyl-3-oxoandrosta-1,4-diene-17\u03b2-carboxylic acid.<\/p>\n $\"Dexamethasone$ <\/p>\n H. 9-fluoro-11\u03b2,17-dihydroxy-16\u03b1-methyl-3,20-dioxopregn-4-en-21-yl dihydrogen phosphate.<\/p>\n","protected":false},"excerpt":{"rendered":" (Ph. Eur. monograph 0549) C22H28FNa2O8P\u00a0 \u00a0 516.4\u00a0 \u00a0 2392-39-4 Action and use Glucocorticoid. Preparations Dexamethasone Sodium Phosphate Eye Drops Dexamethasone Sodium Phosphate Injection Dexamethasone Sodium Phosphate Oral Solution DEFINITION Disodium 9-fluoro-11\u03b2,17-dihydroxy-16\u03b1-methyl-3,20-dioxopregna-1,4-dien-21-yl phosphate. Content 97.0 per cent to 102.0 per cent (anhydrous substance). CHARACTERS Appearance White or almost white, very hygroscopic powder. Solubility Freely soluble in…<\/p>\n","protected":false},"author":3,"featured_media":9288,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-9272","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\/9272","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\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/comments?post=9272"}],"version-history":[{"count":2,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/9272\/revisions"}],"predecessor-version":[{"id":9291,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/9272\/revisions\/9291"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/9288"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=9272"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=9272"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=9272"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}

Content<\/h3>\n97.0 per cent to 102.0 per cent (anhydrous substance).<\/p>\n

CHARACTERS<\/h2>\n

Appearance<\/h3>\nWhite or almost white, very hygroscopic powder.<\/p>\n

Solubility<\/h3>\nFreely soluble in water, slightly soluble in ethanol (96 per cent), practically insoluble in methylene chloride.<\/p>\nIt shows polymorphism (5.9).<\/p>\n

TESTS<\/h2>\n

Solution S<\/h3>\nDissolve 1.0 g in carbon dioxide-free water R and dilute to 20 mL with the same solvent.<\/p>\n

Appearance of solution<\/h3>\nSolution S is clear (2.2.1) and not more intensely coloured than reference solution B7 (2.2.2, Method II).<\/p>\n

pH (2.2.3)<\/h4>\n7.5 to 9.5.<\/p>\nDilute 1 mL of solution S to 5 mL with carbon dioxide-free water R.<\/p>\n

Specific optical rotation (2.2.7)<\/h4>\n+ 75 to + 83 (anhydrous substance).<\/p>\nDissolve 0.250 g in water R and dilute to 25.0 mL with the same solvent.<\/p>\n

Ethanol (2.4.24, System A)<\/h3>\nMaximum 1.5 per cent.<\/p>\n

Water (2.5.12)<\/h4>\nMaximum 10.0 per cent, determined on 0.200 g.<\/p>\n

STORAGE<\/h2>\nIn an airtight container, protected from light.<\/p>\n

Content<\/h3>\n
97.0 per cent to 102.0 per cent (anhydrous substance).<\/p>\n

Appearance<\/h3>\n
White or almost white, very hygroscopic powder.<\/p>\n

Solubility<\/h3>\n
Freely soluble in water, slightly soluble in ethanol (96 per cent), practically insoluble in methylene chloride.<\/p>\n
It shows polymorphism (5.9).<\/p>\n

Solution S<\/h3>\n
Dissolve 1.0 g in carbon dioxide-free water R and dilute to 20 mL with the same solvent.<\/p>\n

Appearance of solution<\/h3>\n
Solution S is clear (2.2.1) and not more intensely coloured than reference solution B7 (2.2.2, Method II).<\/p>\n

pH (2.2.3)<\/h4>\n
7.5 to 9.5.<\/p>\n
Dilute 1 mL of solution S to 5 mL with carbon dioxide-free water R.<\/p>\n

Specific optical rotation (2.2.7)<\/h4>\n
+ 75 to + 83 (anhydrous substance).<\/p>\n
Dissolve 0.250 g in water R and dilute to 25.0 mL with the same solvent.<\/p>\n

Ethanol (2.4.24, System A)<\/h3>\n
Maximum 1.5 per cent.<\/p>\n

Water (2.5.12)<\/h4>\n
Maximum 10.0 per cent, determined on 0.200 g.<\/p>\n

STORAGE<\/h2>\n
In an airtight container, protected from light.<\/p>\n