Glyceryl behenate

• BPGlycerol Dibehenate
• Ph. Eur.Glycerol Dibehenate
• USP–NFGlyceryl Behenate

Compritol 888 ATO; glycerol behenate; glycerol dibehenate; glyceryl dibehenate; docosanoic acid, glycerol ester

Mixture of mono-, di- and triglycerides of behenic (docosanoic) acid, with the diester predominating · [—]

C47H92O5 (glyceryl dibehenate) · 737.2 (glyceryl dibehenate)

Lubricant, Release-modifying polymer

Typical concentrations: 1–3% lubricant · Dosage forms: Solid

Used in oral solid dosage forms as a tablet and capsule lubricant, typically at 1–3% w/w, where it is less sensitive to over-blending than magnesium stearate. At higher levels (often 10% w/w or more) it forms inert lipid matrices for sustained release, and it is also used for hot-melt coating, melt granulation, taste masking and the preparation of solid lipid nanoparticles and microparticles. In cosmetics it acts as a thickener for oily phases.

A fine white powder or hard, waxy mass with a faint odour. Ph. Eur. specifies about 15–23% monoacylglycerols, 40–60% diacylglycerols and 21–35% triacylglycerols, with behenic acid as the main fatty acid.

Melting range

about 65–77 °C

HLB

≈ 2

Saponification value

145–165

Iodine value

≤ 3 (saturated)

Solubility

soluble in chloroform and dichloromethane when heated; practically insoluble in water, ethanol, hexane and mineral oil

Chemically stable. Store in a tightly closed container below about 35 °C, protected from heat; partial melting and resolidification can change its crystalline form and its release behaviour.

No significant chemical incompatibilities have been reported. Like other hydrophobic lubricants it can slow tablet disintegration and drug dissolution if used in excess.

Made by esterifying glycerol with behenic acid, obtained from hydrogenated rapeseed or similar oils, without a catalyst; the product is then atomised (spray-cooled) to give a fine powder.

Used in oral pharmaceutical products and in cosmetics, and regarded as essentially non-toxic and non-irritant.

Observe normal precautions for the quantity handled; eye protection and gloves are recommended, with a dust mask where dust is generated.

GRAS listed. Included in the FDA Inactive Ingredient Database (oral capsules and tablets) and in non-parenteral medicines licensed in Europe.

Glyceryl monostearate; glyceryl palmitostearate; hydrogenated vegetable oil; magnesium stearate.

As a lubricant it is a useful alternative where magnesium stearate causes incompatibility, softening of tablets or slow dissolution, although higher levels are usually needed. In matrix tablets the release rate can be adjusted by changing its proportion, adding hydrophilic fillers or channelling agents, and by thermal treatment.