Aqueous compositions comprising of lipid and a lanolin-derived surfactant, and their use

摘要

An aqueous composition comprising, in addition to water: (a) one or more surfactant materials selected from polyoxyalkylene condensate derivatives of lanolin or a lanolin derivative; and (b) a lipid component comprising one or more lipid materials, especially lanolin or a lanolin derivative, present as particles emulsified by the said one or more lanolin-derived surfactant materials and having a median particle size of less than about 5 microns, especially from 0.01 to 1 microns. The compositions have very good physical stability and are particularly useful as carriers for transdermal delivery of pharmaceutical actives to the human skin. Wool wax or purified lanolin (lanolin purified to varying levels of removed impurities such as allergens and pesticides) may be used as a lanolin per se lipid component. Such lanolin may be hydrous or, more preferably, anhydrous. Physically or chemically obtained lanolin derivatives suitable for use as a lanolin-derived lipid component may include for example lanolin oil, lanolin alcohols and lanolin esters (e.g. isopropyl lanolate). Other lipid materials which may be suitable for use as or in the lipid component of the compositions include the following: (i) waxes, e.g. esters of monohydric alcohols of the higher homologues; (ii) long chain hydocarbons, e.g. C12 to C60 hydrocarbons; (iii) fat, in particular glycerides (e.g. mono-, di-, or triglycerides) of higher fatty acids; (iv) oils, suh as: (a) fatty oils derived from animal, vegetable or marine sources, e.g. mono-, di-, or triglycerides of fatty acids; (b) mineral oils, e.g. non-volatile hydrocarbons; (c) essential oils, e.g. plant-derived volatile or non-volatile oils; (v) neutal glycerolipids, e.g. mono-, di-, and tri acylglycerols and their neutral derivatives (e.g. alkoxy and polyalkoxy derivatives), acyl derivatives of glycerophospholipids and mono- and di galactoacylglycerols; (vi) polar lipids, e.g. glycerophospholipids, sphingomyelins, galactosylacylglycerols; (vi) phospholipids; (vii) terpenes; (viii) sterols;x) ceramides