Lanolin hydrous

Simone and Popino have considered the stability of neomycin in both hydrophobic and hydrophilic ointment bases. No loss of potency over a period of 1 year at 20°C was reported for formulations containing carboxymethylcellulose, polyethylene glycol(P.E.G.) or white-soft paraffin. However, formulations containing hydrous lanolin were reported to be unstable. All materials used in the formulations were obtained from U.S. sources. Coates et al3°l investigated the use of P.E.G. from British sources and described neomycin as being incompatible with the materials tested. 

The unsaponifiables of woolwax, known as woolwax alcohols, are in considerable demand by cosmetic and pharmaceutical industries. Woolwax has a great affinity for water, of which it will absorb 25 to 30%. Refined woolwax is kneaded with water to produce a water-white, colorless oiiilmenL, known as hydrous lanolin or lanolin USP. Anhydrous lanolin is widely used in cosmetic creams, since it is readily absorbed by the skin. It is also used m leather dressings and shoe pastes, as a superfatting agent for toilet soap, as a protective coating for metals, etc. United States consumption of wool wax is about 1.5 million lb/year. 

Hydrous lanolin Hydrous wool fat, Lipolan BP, JP, PhEur Melting range 38-44 °C acid value <0.8 saponification value 67-79 nonvolatile matter 72.5-77.5% iodine value 18-36 ... 

Cholesterol hydrogenated lanolin lanolin, hydrous lanolin alcohols modified lanolin. 

Lanolin (the anhydrous material) may be confused in some instances with hydrous lanolin since the USP formerly contained monographs for lanolin and anhydrous lanolin in which the name lanolin referred to the material containing 25-30% w/w of purified water. However, in the USP 28 the former lanolin monograph (hydrous lanolin) is deleted and the monograph for anhydrous lanolin is renamed lanolin . 

The JP 2001 describes hydrous lanolin as a mixture of lanolin and 25-30% w/w purified water. The PhEur 2005 describes hydrous lanolin as a mixture of lanolin and 25% w/w purified water see also Section 18. The PhEur 2005 additionally permits the inclusion of up to 150 ppm of butylated hydroxy-toluene as an antioxidant. 

Hydrous lanolin is widely used in topical pharmaceutical formulations and cosmetics in applications similar to those for lanolin. 

Hydrous lanolin is commonly used in the preparation of water-in-oil creams and ointments. More water may be incorporated into hydrous lanolin than into lanolin. 

Hydrous lanolin is a pale yellow-colored, unctuous substance with a faint characteristic odor. When melted by heating on a water bath, hydrous lanolin separates into a clear oily layer and a clear water layer. 

Solubility practically insoluble in chloroform, ether, and water. Only the fat component of hydrous lanolin is soluble in organic solvents. 

Hydrous lanolin should be stored in a well-filled, well-closed container protected from light, in a cool, dry place. Normal storage life is 2 years. 

Hydrous lanolin is used in cosmetics and a number of topical pharmaceutical formulations and is generally regarded as a nontoxic and nonirritant material, although it has been associated with hypersensitivity reactions. See Lanolin for further information. 

Cholesterol lanolin lanolin, hydrous petrolatum and lanolin alcohols mineral oils. 

Hydrous Wool Fat (Lanolin). This is wool fat with 30 per cent of water. The moisture may be determined by direct drying of a thin layer in an oven at 100°, or preferably, by distillation with an immiscible solvent (p. 803). 

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