{"id":29187,"date":"2025-11-10T15:19:26","date_gmt":"2025-11-10T08:19:26","guid":{"rendered":"https:\/\/nhathuocngocanh.com\/bp\/?p=29187"},"modified":"2025-11-10T15:19:26","modified_gmt":"2025-11-10T08:19:26","slug":"tetracaine-hydrochloride","status":"publish","type":"post","link":"https:\/\/nhathuocngocanh.com\/bp\/tetracaine-hydrochloride\/","title":{"rendered":"Tetracaine Hydrochloride"},"content":{"rendered":"

(Ph. Eur. 11.6 update)<\/p>\n

(Ph. Eur. monograph 0057)<\/p>\n

$\"C15H25ClN2O2\"$ C_{15<\/sub>H_{25<\/sub>ClN_{2<\/sub>O_{2<\/sub>\u00a0 \u00a0 \u00a0 \u00a0 \u00a0300.8\u00a0 \u00a0 \u00a0 \u00a0 136-47-0<\/p>\n}}}}

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

Local anaesthetic.<\/p>\n

Preparation<\/strong><\/p>\n

Tetracaine Eye Drops<\/p>\n

Ph Eur<\/p>\n

DEFINITION<\/h2>\n
2-(Dimethylamino)ethyl 4-(butylamino)benzoate hydrochloride.<\/p>\n
Content<\/strong><\/p>\n
99.0 per cent to 101.0 per cent (dried substance).<\/p>\n
CHARACTERS<\/h2>\n
Appearance<\/strong><\/p>\n
White or almost white, slightly hygroscopic, crystalline powder.<\/p>\n
Solubility<\/strong><\/p>\n
Freely soluble in water, soluble in ethanol (96 per cent), practically insoluble in heptane.<\/p>\n
It shows polymorphism (5.9).<\/p>\n
mp<\/strong><\/p>\n
134\u00b0C to 150\u00b0C.<\/p>\n
IDENTIFICATION<\/h2>\n
First identification: A, D.<\/p>\n
Second identification: B, C, D.<\/p>\n
A. Infrared absorption spectrophotometry (2.2.24), without recrystallisation.<\/p>\n
Comparison tetracaine hydrochloride CRS.<\/p>\n
B. To 10 mL of solution S (see Tests) add 1 mL of ammonium thiocyanate solution R. A white, crystalline precipitate is formed, which, after recrystallisation from water R and drying at 80 \u00b0C for 2 h, melts (2.2.14) at about 131 \u00b0C.<\/p>\n
C. To about 5 mg add 0.5 mL of fuming nitric acid R. Evaporate to dryness on a water-bath, allow to cool and dissolve the residue in 5 mL of acetone R. Add 1 mL of 0.1 M alcoholic potassium hydroxide. A violet colour develops.<\/p>\n
D. Solution S gives reaction (a) of chlorides (2.3.1).<\/p>\n
TESTS<\/h2>\n
Solution S<\/strong><\/p>\n
Dissolve 5.0 g in carbon dioxide-free water R and dilute to 50 mL with the same solvent.<\/p>\n
Appearance of solution<\/strong><\/p>\n
The solution is clear (2.2.1) and colourless (2.2.2, Method II).<\/p>\n
Dilute 2 mL of solution S to 10 mL with water R.<\/p>\n
pH (2.2.3)<\/p>\n
4.5 to 6.5.<\/p>\n
Dilute 1 mL of solution S to 10 mL with carbon dioxide-free water R.<\/p>\n
Related substances<\/strong><\/p>\n
Liquid chromatography (2.2.29). Prepare the solutions immediately before use.<\/p>\n
Solvent mixture acetonitrile R, water R (20:80 V\/V).<\/p>\n
Test solution Dissolve 20.0 mg of the substance to be examined in the solvent mixture and dilute to 20.0 mL with the solvent mixture.<\/p>\n
Reference solution (a) Dilute 1.0 mL of the test solution to 100.0 mL with the solvent mixture. Dilute 1.0 mL of this solution to 10.0 mL with the solvent mixture.<\/p>\n
Reference solution (b) Dissolve the contents of a vial of tetracaine for system suitability CRS (containing impurities A, B and C) in 2 mL of the solvent mixture.<\/p>\n
Column:<\/p>\n
\u2014 size: l = 0.15 m, \u00d8 = 4.6 mm;<\/p>\n
\u2014 stationary phase: silica gel for chromatography, alkyl-bonded for use with highly aqueous mobile phases R (5 \u03bcm);<\/p>\n
\u2014 temperature: 30\u00b0C.<\/p>\n
Mobile phase:<\/p>\n
\u2014 mobile phase A: dissolve 1.36 g of potassium dihydrogen phosphate R in water for chromatography R, add 0.5 mL of phosphoric acid R and dilute to 1000 mL with water for chromatography R;<\/p>\n
\u2014 mobile phase B: acetonitrile R;<\/p>\n\n\n\n\n\n\n
Time (min) <\/strong><\/td>\n Mobile phase A (per cent V\/V)<\/strong><\/td>\n Mobile phase B (per cent V\/V)<\/strong><\/td>\n<\/tr>\n
0 – 3<\/td>\n 80<\/td>\n 20<\/td>\n<\/tr>\n
3 – 18<\/td>\n \u00a080 \u2192 4<\/td>\n 20 \u2192 60<\/td>\n<\/tr>\n
18 – 23<\/td>\n 40<\/td>\n 60<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
Flow rate 1.5 mL\/min.<\/p>\n
Detection Spectrophotometer at 300 nm.<\/p>\n
Injection 10 \u03bcL.<\/p>\n
Identification of impurities Use the chromatogram supplied with tetracaine for system suitability CRS and the chromatogram obtained with reference solution (b) to identify the peaks due to impurities A, B and C.<\/p>\n
Relative retention With reference to tetracaine (retention time = about 7 min): impurity A = about 0.3; impurity B = about 1.6; impurity C = about 2.2.<\/p>\n
System suitability Reference solution (b):<\/p>\n
\u2014 resolution: minimum 5.0 between the peaks due to tetracaine and impurity B.<\/p>\n
Calculation of percentage contents:<\/p>\n
\u2014 correction factors: multiply the peak areas of the following impurities by the corresponding correction factor: impurity B = 0.7; impurity C = 0.7;<\/p>\n
\u2014 for each impurity, use the concentration of tetracaine hydrochloride in reference solution (a).<\/p>\n
Limits:<\/p>\n
\u2014 impurities B, C: for each impurity, maximum 0.15 per cent;<\/p>\n
\u2014 impurity A: maximum 0.05 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 reporting threshold: 0.05 per cent, except for impurity A.<\/p>\n
Loss on drying (2.2.32)<\/p>\n
Maximum 1.0 per cent, determined on 1.000 g by drying in an oven at 105 \u00b0C.<\/p>\n
Sulfated ash (2.4.14)<\/p>\n
Maximum 0.1 per cent, determined on 1.0 g.<\/p>\n
ASSAY<\/h2>\n
Dissolve 0.250 g in 50 mL of ethanol (96 per cent) R and add 5.0 mL of a 1.03 g\/L solution of hydrochloric acid R.<\/p>\n
Carry out a potentiometric titration (2.2.20), using 0.1 M sodium hydroxide.<\/p>\n
Read the volume added between the 2 points of inflexion.<\/p>\n
1 mL of 0.1 M sodium hydroxide is equivalent to 30.08 mg of C_{15<\/sub>H_{25<\/sub>ClN_{2<\/sub>O_{2<\/sub><\/p>\n}}}}
STORAGE<\/h2>\n
In an airtight container, protected from light.<\/p>\n
IMPURITIES<\/h2>\n
Specified impurities A, B, C.<\/p>\n
$\"A.$ <\/p>\n
A. 4-aminobenzoic acid,<\/p>\n
$\"B.$ <\/p>\n
B. 4-(butylamino)benzoic acid,<\/p>\n
$\"C.$ <\/p>\n
C. methyl 4-(butylamino)benzoate<\/p>\n","protected":false},"excerpt":{"rendered":"
(Ph. Eur. 11.6 update) (Ph. Eur. monograph 0057) C15H25ClN2O2\u00a0 \u00a0 \u00a0 \u00a0 \u00a0300.8\u00a0 \u00a0 \u00a0 \u00a0 136-47-0 Action and use Local anaesthetic. Preparation Tetracaine Eye Drops Ph Eur DEFINITION 2-(Dimethylamino)ethyl 4-(butylamino)benzoate hydrochloride. Content 99.0 per cent to 101.0 per cent (dried substance). CHARACTERS Appearance White or almost white, slightly hygroscopic, crystalline powder. Solubility Freely soluble…<\/p>\n","protected":false},"author":4,"featured_media":29205,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-29187","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\/29187","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\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/comments?post=29187"}],"version-history":[{"count":2,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/29187\/revisions"}],"predecessor-version":[{"id":29242,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/29187\/revisions\/29242"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/29205"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=29187"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=29187"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=29187"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}

Time (min) <\/strong><\/td>\n	Mobile phase A (per cent V\/V)<\/strong><\/td>\n	Mobile phase B (per cent V\/V)<\/strong><\/td>\n<\/tr>\n
0 – 3<\/td>\n	80<\/td>\n	20<\/td>\n<\/tr>\n
3 – 18<\/td>\n	\u00a080 \u2192 4<\/td>\n	20 \u2192 60<\/td>\n<\/tr>\n
18 – 23<\/td>\n	40<\/td>\n	60<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Flow rate 1.5 mL\/min.<\/p>\n Detection Spectrophotometer at 300 nm.<\/p>\n Injection 10 \u03bcL.<\/p>\n Identification of impurities Use the chromatogram supplied with tetracaine for system suitability CRS and the chromatogram obtained with reference solution (b) to identify the peaks due to impurities A, B and C.<\/p>\n Relative retention With reference to tetracaine (retention time = about 7 min): impurity A = about 0.3; impurity B = about 1.6; impurity C = about 2.2.<\/p>\n System suitability Reference solution (b):<\/p>\n \u2014 resolution: minimum 5.0 between the peaks due to tetracaine and impurity B.<\/p>\n Calculation of percentage contents:<\/p>\n \u2014 correction factors: multiply the peak areas of the following impurities by the corresponding correction factor: impurity B = 0.7; impurity C = 0.7;<\/p>\n \u2014 for each impurity, use the concentration of tetracaine hydrochloride in reference solution (a).<\/p>\n Limits:<\/p>\n \u2014 impurities B, C: for each impurity, maximum 0.15 per cent;<\/p>\n \u2014 impurity A: maximum 0.05 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 reporting threshold: 0.05 per cent, except for impurity A.<\/p>\n Loss on drying (2.2.32)<\/p>\n Maximum 1.0 per cent, determined on 1.000 g by drying in an oven at 105 \u00b0C.<\/p>\n Sulfated ash (2.4.14)<\/p>\n Maximum 0.1 per cent, determined on 1.0 g.<\/p>\n ASSAY<\/h2>\n Dissolve 0.250 g in 50 mL of ethanol (96 per cent) R and add 5.0 mL of a 1.03 g\/L solution of hydrochloric acid R.<\/p>\n Carry out a potentiometric titration (2.2.20), using 0.1 M sodium hydroxide.<\/p>\n Read the volume added between the 2 points of inflexion.<\/p>\n 1 mL of 0.1 M sodium hydroxide is equivalent to 30.08 mg of C_{15<\/sub>H_{25<\/sub>ClN_{2<\/sub>O_{2<\/sub><\/p>\n}}}} STORAGE<\/h2>\n In an airtight container, protected from light.<\/p>\n IMPURITIES<\/h2>\n Specified impurities A, B, C.<\/p>\n $\"A.$ <\/p>\n A. 4-aminobenzoic acid,<\/p>\n $\"B.$ <\/p>\n B. 4-(butylamino)benzoic acid,<\/p>\n $\"C.$ <\/p>\n C. methyl 4-(butylamino)benzoate<\/p>\n","protected":false},"excerpt":{"rendered":" (Ph. Eur. 11.6 update) (Ph. Eur. monograph 0057) C15H25ClN2O2\u00a0 \u00a0 \u00a0 \u00a0 \u00a0300.8\u00a0 \u00a0 \u00a0 \u00a0 136-47-0 Action and use Local anaesthetic. Preparation Tetracaine Eye Drops Ph Eur DEFINITION 2-(Dimethylamino)ethyl 4-(butylamino)benzoate hydrochloride. Content 99.0 per cent to 101.0 per cent (dried substance). CHARACTERS Appearance White or almost white, slightly hygroscopic, crystalline powder. Solubility Freely soluble…<\/p>\n","protected":false},"author":4,"featured_media":29205,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-29187","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\/29187","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\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/comments?post=29187"}],"version-history":[{"count":2,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/29187\/revisions"}],"predecessor-version":[{"id":29242,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/29187\/revisions\/29242"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/29205"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=29187"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=29187"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=29187"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}

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

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