{"id":17335,"date":"2025-10-22T10:16:21","date_gmt":"2025-10-22T03:16:21","guid":{"rendered":"https:\/\/nhathuocngocanh.com\/bp\/?p=17335"},"modified":"2025-10-22T10:16:21","modified_gmt":"2025-10-22T03:16:21","slug":"lactose","status":"publish","type":"post","link":"https:\/\/nhathuocngocanh.com\/bp\/lactose\/","title":{"rendered":"Lactose"},"content":{"rendered":"

Lactose^{1<\/sup><\/p>\n}

Anhydrous Lactose<\/p>\n

(Ph. Eur. monograph 1061)<\/em><\/p>\n

C_{12<\/sub>H_{22<\/sub>O_{11<\/sub> 342.3 63-42-3<\/p>\n}}}

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

Excipient.<\/p>\n

DEFINITION<\/h2>\n
O-\u03b2-D-Galactopyranosyl-(1\u21924)-\u03b2-D-glucopyranose or mixture of O-\u03b2-D-galactopyranosyl-(1\u21924)-\u03b1-D-glucopyranose and O-\u03b2-D-galactopyranosyl-(1\u21924)-\u03b2-D-glucopyranose.<\/p>\n
CHARACTERS<\/h2>\n
Appearance<\/h3>\n
White or almost white, crystalline powder.<\/p>\n
Solubility<\/h3>\n
Freely soluble in water, practically insoluble in ethanol (96 per cent).\u2666<\/p>\n
IDENTIFICATION<\/h2>\n
First identification: A, \u2662 D.<\/p>\n
Second identification: B, C, D.\u2662<\/p>\n
A. Infrared absorption spectrophotometry (2.2.24).<\/p>\n
Comparison: anhydrous lactose CRS.<\/p>\n
B. Thin-layer chromatography (2.2.27).<\/p>\n
Solvent mixture water R, methanol R (40:60 V\/V).<\/p>\n
Test solution: Dissolve 10 mg of the substance to be examined in the solvent mixture and dilute to 20 mL with the solvent mixture.<\/p>\n
Reference solution: Dissolve 10 mg of anhydrous lactose CRS in the solvent mixture and dilute to 20 mL with the solvent mixture.<\/p>\n
Plate: TLC silica gel plate R.<\/p>\n
Mobile phase: water R, methanol R, glacial acetic acid R, methylene chloride R (10:15:25:50 V\/V\/V\/V); measure the volumes accurately, as a slight excess of water produces cloudiness.<\/p>\n
Application: 2 \u03bcL; thoroughly dry the points of application.<\/p>\n
Development A: Over 3\/4 of the plate.<\/p>\n
Drying A: In a current of warm air.<\/p>\n
Development B: Immediately, over 3\/4 of the plate, after renewing the mobile phase.<\/p>\n
Drying B: In a current of warm air.<\/p>\n
Detection: Spray with a solution of 0.5 g of thymol R in a mixture of 5 mL of sulfuric acid R and 95 mL of ethanol (96 per cent) R; heat at 130 \u00b0C for 10 min.<\/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. Dissolve 0.25 g in 5 mL of water R. Add 5 mL of ammonia R and heat in a water-bath at 80 \u00b0C for 10 min. A red colour develops.<\/p>\n
D. Water (see Tests).\u2662<\/p>\n
TESTS<\/h2>\n
Solution S<\/h3>\n
Dissolve 1.0 g in boiling water R, allow to cool and dilute to 10.0 mL with water R.<\/p>\n
Appearance of solution<\/h3>\n
Solution S is clear (2.2.1) and not more intensely coloured than reference solution BY7 (2.2.2, Method II).<\/p>\n
Acidity or alkalinity<\/h3>\n
Dissolve 6.0 g by heating in 25 mL of carbon dioxide-free water R, cool and add 0.3 mL of phenolphthalein solution R1. The solution is colourless. Not more than 0.4 mL of 0.1 M sodium hydroxide is required to change the colour of the indicator to pink or red.<\/p>\n
Specific optical rotation (2.2.7)<\/h3>\n
+ 54.4 to + 55.9 (anhydrous substance).<\/p>\n
Dissolve 10.0 g in 80 mL of water R with heating at 50 \u00b0C. Allow to cool and add 0.2 mL of dilute ammonia R1. Allow to stand for 30 min and dilute to 100.0 mL with water R.<\/p>\n
Absorbance: proteins and light-absorbing impurities (2.2.25)<\/h3>\n
Test solution (a): Solution S.<\/p>\n
Test solution (b): Dilute 1.0 mL of test solution (a) to 10.0 mL with water R.<\/p>\n
Spectral range 400 nm for test solution (a) and 210-300 nm for test solution (b).<\/p>\n
Results:<\/p>\n
\u2014 at 400 nm: maximum 0.04 for test solution (a);<\/p>\n
\u2014 from 210 nm to 220 nm: maximum 0.25 for test solution (b);<\/p>\n
\u2014 from 270 nm to 300 nm: maximum 0.07 for test solution (b).<\/p>\n
Water (2.5.12)<\/h3>\n
Maximum 1.0 per cent, determined on 1.00 g, using a mixture of 1 volume of formamide R and 2 volumes of methanol R as solvent.<\/p>\n
Sulfated ash (2.4.14)<\/h3>\n
Maximum 0.1 per cent, determined on 1.0 g.<\/p>\n
Microbial contamination<\/h3>\n
TAMC: acceptance criterion 10 CFU\/g (2.6.12).<\/p>\n
Absence of: Escherichia coli (2.6.13).<\/p>\n
FUNCTIONALITY-RELATED CHARACTERISTICS<\/h2>\n
This section provides information on characteristics that are recognised as being relevant control parameters for one or more functions of the substance when used as an excipient (see chapter 5.15<\/p>\n
Some of the characteristics described in the Functionality-related characteristics section may also be present in the mandatory part of the monograph since they also represent mandatory quality criteria. In such cases, a cross-reference to the tests described in the mandatory part is included in the Functionality-related characteristics section. Control of the characteristics can contribute to the quality of a medicinal product by improving the consistency of the manufacturing process and the performance of the medicinal product during use. Where control methods are cited, they are recognised as being suitable for the purpose, but other methods can also be used. Wherever results for a particular characteristic are reported, the control method must be indicated.<\/p>\n
The following characteristics may be relevant for lactose used as filler\/diluent in solid dosage forms (compressed and powder).<\/p>\n
Particle-size distribution (2.9.31 or 2.9.38)<\/h3>\n
Bulk density of powders (2.9.34)<\/p>\n
\u03b1-Lactose and \u03b2-lactose<\/h3>\n
Gas chromatography (2.2.28).<\/p>\n
Silylation reagent dimethyl sulfoxide R, N-trimethylsilylimidazole R, pyridine R (19.5:22:58.5 V\/V\/V).<\/p>\n
Test solution: Introduce 10 mg of the substance to be examined into a vial with a screw cap and add 4 mL of the silylation reagent. Sonicate for 20 min at room temperature, allow to cool and transfer 400 \u03bcL to an injection vial. Add 1 mL of pyridine R, close the vial and mix well.<\/p>\n
Reference solution: Prepare a mixture of \u03b1-lactose monohydrate R and \u03b2-lactose R to obtain an anomeric ratio of about 1:1 based on the labelled anomeric contents of the \u03b1-lactose monohydrate and the \u03b2-lactose.<\/p>\n
Introduce 10 mg of the mixture into a vial with a screw cap and add 4 mL of the silylation reagent. Sonicate for 20 min at room temperature, allow to cool, and transfer 400 \u03bcL to an injection vial. Add 1 mL of pyridine R, close the vial and mix well.<\/p>\n
Precolumn:<\/p>\n
\u2014 material: intermediate-polarity deactivated fused silica;<\/p>\n
\u2014 size: l = 2 m, \u00d8 = 0.53 mm.<\/p>\n
Column:<\/p>\n
\u2014 material: fused silica;<\/p>\n
\u2014 size: l = 15 m, \u00d8 = 0.25 mm;<\/p>\n
\u2014 stationary phase: phenyl(5)methyl(95)polysiloxane R (film thickness 0.25 \u03bcm).<\/p>\n
Carrier: gas helium for chromatography R.<\/p>\n
Flow rate: 2.8 mL\/min.<\/p>\n
Temperature:<\/p>\n\n\n\n\n\n\n\n\n\n
<\/td>\n Time<\/strong><\/p>\n
(min)<\/strong><\/td>\n
Temperature<\/strong><\/p>\n
(\u00b0C)<\/strong><\/td>\n<\/tr>\n
Column<\/td>\n 0 – 1<\/td>\n 80<\/td>\n<\/tr>\n
<\/td>\n 1 – 3<\/td>\n 80 \u2192 150<\/td>\n<\/tr>\n
<\/td>\n 3 – 15.5<\/td>\n 150 \u2192 300<\/td>\n<\/tr>\n
<\/td>\n 15.5 – 17.5<\/td>\n 300<\/td>\n<\/tr>\n
Injection port<\/td>\n <\/td>\n 275 or use cold on-column injection<\/td>\n<\/tr>\n
Detector<\/td>\n <\/td>\n 325<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
Detection: Flame ionisation.<\/p>\n
Injection: 0.5 \u03bcL, splitless or by cold on-column injection.<\/p>\n
Relative retention: With reference to \u03b2-lactose (retention time = about 12 min): \u03b1-lactose = about 0.9.<\/p>\n
System suitability: Reference solution:<\/p>\n
\u2014 resolution: minimum 3.0 between the peaks due to \u03b1-lactose and \u03b2-lactose.<\/p>\n
Calculate the percentage content of \u03b1-lactose using the following expression:<\/p>\n
100 S_{a<\/sub>\/ (S_{a<\/sub> + S_{b<\/sub>)<\/p>\n}}}
Calculate the percentage content of \u03b2-lactose using the following expression:<\/p>\n
100 S_{b<\/sub>\/ (S_{a<\/sub> + S_{b<\/sub>)<\/p>\n}}}
S_{a<\/sub> = area of the peak due to \u03b1-lactose;<\/p>\n}
S_{b<\/sub> = area of the peak due to \u03b2-lactose.<\/p>\n}
Loss on drying (2.2.32)<\/h3>\n
Determine on 1.000 g by drying in an oven at 80 \u00b0C for 2 h.<\/p>\n
^{1<\/sup> This monograph has undergone pharmacopoeial harmonisation. See chapter 5.8. Pharmacopoeial harmonisation.<\/p>\n","protected":false},"excerpt":{"rendered":"}
Lactose1 Anhydrous Lactose (Ph. Eur. monograph 1061) C12H22O11 342.3 63-42-3 Action and use Excipient. DEFINITION O-\u03b2-D-Galactopyranosyl-(1\u21924)-\u03b2-D-glucopyranose or mixture of O-\u03b2-D-galactopyranosyl-(1\u21924)-\u03b1-D-glucopyranose and O-\u03b2-D-galactopyranosyl-(1\u21924)-\u03b2-D-glucopyranose. CHARACTERS Appearance White or almost white, crystalline powder. Solubility Freely soluble in water, practically insoluble in ethanol (96 per cent).\u2666 IDENTIFICATION First identification: A, \u2662 D. Second identification: B, C, D.\u2662 A. Infrared…<\/p>\n","protected":false},"author":4,"featured_media":17364,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-17335","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\/17335","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=17335"}],"version-history":[{"count":2,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/17335\/revisions"}],"predecessor-version":[{"id":17366,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/17335\/revisions\/17366"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/17364"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=17335"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=17335"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=17335"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}

<\/td>\n	Time<\/strong><\/p>\n (min)<\/strong><\/td>\n	Temperature<\/strong><\/p>\n (\u00b0C)<\/strong><\/td>\n<\/tr>\n
Column<\/td>\n	0 – 1<\/td>\n	80<\/td>\n<\/tr>\n
<\/td>\n	1 – 3<\/td>\n	80 \u2192 150<\/td>\n<\/tr>\n
<\/td>\n	3 – 15.5<\/td>\n	150 \u2192 300<\/td>\n<\/tr>\n
<\/td>\n	15.5 – 17.5<\/td>\n	300<\/td>\n<\/tr>\n
Injection port<\/td>\n	<\/td>\n	275 or use cold on-column injection<\/td>\n<\/tr>\n
Detector<\/td>\n	<\/td>\n	325<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Detection: Flame ionisation.<\/p>\n Injection: 0.5 \u03bcL, splitless or by cold on-column injection.<\/p>\n Relative retention: With reference to \u03b2-lactose (retention time = about 12 min): \u03b1-lactose = about 0.9.<\/p>\n System suitability: Reference solution:<\/p>\n \u2014 resolution: minimum 3.0 between the peaks due to \u03b1-lactose and \u03b2-lactose.<\/p>\n Calculate the percentage content of \u03b1-lactose using the following expression:<\/p>\n 100 S_{a<\/sub>\/ (S_{a<\/sub> + S_{b<\/sub>)<\/p>\n}}} Calculate the percentage content of \u03b2-lactose using the following expression:<\/p>\n 100 S_{b<\/sub>\/ (S_{a<\/sub> + S_{b<\/sub>)<\/p>\n}}} S_{a<\/sub> = area of the peak due to \u03b1-lactose;<\/p>\n} S_{b<\/sub> = area of the peak due to \u03b2-lactose.<\/p>\n} Loss on drying (2.2.32)<\/h3>\n Determine on 1.000 g by drying in an oven at 80 \u00b0C for 2 h.<\/p>\n ^{1<\/sup> This monograph has undergone pharmacopoeial harmonisation. See chapter 5.8. Pharmacopoeial harmonisation.<\/p>\n","protected":false},"excerpt":{"rendered":"} Lactose1 Anhydrous Lactose (Ph. Eur. monograph 1061) C12H22O11 342.3 63-42-3 Action and use Excipient. DEFINITION O-\u03b2-D-Galactopyranosyl-(1\u21924)-\u03b2-D-glucopyranose or mixture of O-\u03b2-D-galactopyranosyl-(1\u21924)-\u03b1-D-glucopyranose and O-\u03b2-D-galactopyranosyl-(1\u21924)-\u03b2-D-glucopyranose. CHARACTERS Appearance White or almost white, crystalline powder. Solubility Freely soluble in water, practically insoluble in ethanol (96 per cent).\u2666 IDENTIFICATION First identification: A, \u2662 D. Second identification: B, C, D.\u2662 A. Infrared…<\/p>\n","protected":false},"author":4,"featured_media":17364,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-17335","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\/17335","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=17335"}],"version-history":[{"count":2,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/17335\/revisions"}],"predecessor-version":[{"id":17366,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/17335\/revisions\/17366"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/17364"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=17335"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=17335"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=17335"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}

CHARACTERS<\/h2>\n

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

Solubility<\/h3>\nFreely soluble in water, practically insoluble in ethanol (96 per cent).\u2666<\/p>\n

TESTS<\/h2>\n

Solution S<\/h3>\nDissolve 1.0 g in boiling water R, allow to cool and dilute to 10.0 mL with water R.<\/p>\n

Appearance of solution<\/h3>\nSolution S is clear (2.2.1) and not more intensely coloured than reference solution BY7 (2.2.2, Method II).<\/p>\n

Acidity or alkalinity<\/h3>\nDissolve 6.0 g by heating in 25 mL of carbon dioxide-free water R, cool and add 0.3 mL of phenolphthalein solution R1. The solution is colourless. Not more than 0.4 mL of 0.1 M sodium hydroxide is required to change the colour of the indicator to pink or red.<\/p>\n

Specific optical rotation (2.2.7)<\/h3>\n+ 54.4 to + 55.9 (anhydrous substance).<\/p>\nDissolve 10.0 g in 80 mL of water R with heating at 50 \u00b0C. Allow to cool and add 0.2 mL of dilute ammonia R1. Allow to stand for 30 min and dilute to 100.0 mL with water R.<\/p>\n

Water (2.5.12)<\/h3>\nMaximum 1.0 per cent, determined on 1.00 g, using a mixture of 1 volume of formamide R and 2 volumes of methanol R as solvent.<\/p>\n

Sulfated ash (2.4.14)<\/h3>\nMaximum 0.1 per cent, determined on 1.0 g.<\/p>\n

Microbial contamination<\/h3>\nTAMC: acceptance criterion 10 CFU\/g (2.6.12).<\/p>\nAbsence of: Escherichia coli (2.6.13).<\/p>\n

Particle-size distribution (2.9.31 or 2.9.38)<\/h3>\nBulk density of powders (2.9.34)<\/p>\n

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

Solubility<\/h3>\n
Freely soluble in water, practically insoluble in ethanol (96 per cent).\u2666<\/p>\n

Solution S<\/h3>\n
Dissolve 1.0 g in boiling water R, allow to cool and dilute to 10.0 mL with water R.<\/p>\n

Appearance of solution<\/h3>\n
Solution S is clear (2.2.1) and not more intensely coloured than reference solution BY7 (2.2.2, Method II).<\/p>\n

Acidity or alkalinity<\/h3>\n
Dissolve 6.0 g by heating in 25 mL of carbon dioxide-free water R, cool and add 0.3 mL of phenolphthalein solution R1. The solution is colourless. Not more than 0.4 mL of 0.1 M sodium hydroxide is required to change the colour of the indicator to pink or red.<\/p>\n

Specific optical rotation (2.2.7)<\/h3>\n
+ 54.4 to + 55.9 (anhydrous substance).<\/p>\n
Dissolve 10.0 g in 80 mL of water R with heating at 50 \u00b0C. Allow to cool and add 0.2 mL of dilute ammonia R1. Allow to stand for 30 min and dilute to 100.0 mL with water R.<\/p>\n

Water (2.5.12)<\/h3>\n
Maximum 1.0 per cent, determined on 1.00 g, using a mixture of 1 volume of formamide R and 2 volumes of methanol R as solvent.<\/p>\n

Sulfated ash (2.4.14)<\/h3>\n
Maximum 0.1 per cent, determined on 1.0 g.<\/p>\n

Microbial contamination<\/h3>\n
TAMC: acceptance criterion 10 CFU\/g (2.6.12).<\/p>\n
Absence of: Escherichia coli (2.6.13).<\/p>\n

Particle-size distribution (2.9.31 or 2.9.38)<\/h3>\n
Bulk density of powders (2.9.34)<\/p>\n