Name: Cetostearyl Alcohol
CAS No: Cetostearyl alcohol [67762-27-0] and [8005-44-5]
BP: Cetostearyl Alcohol PhEur: Cetostearyl Alcohol USP-NF: Cetostearyl Alcohol
Alcohol cetylicus et stearylicus; cetearyl alcohol; cetyl stearyl alcohol; Crodacol CS90; Lanette O; Speziol C16-18 Pharma; Tego Alkanol 1618; Tego Alkanol 6855.
Cetostearyl alcohol [67762-27-0] and [8005-44-5]
Cetostearyl alcohol is a mixture of solid aliphatic alcohols consisting mainly of stearyl (C18H38O) and cetyl (C16H34O) alcohols. The proportion of stearyl to cetyl alcohol varies considerably, but the material usually consists of about 50–70% stearyl alcohol and 20–35% cetyl alcohol, with limits specified in pharmacopeias. The combined stearyl alcohol and cetyl alcohol comprise at least 90% of the material. Small quantities of other alcohols, chiefly myristyl alcohol, make up the remainder of the material
See Section 4
Cetostearyl alcohol is used in cosmetics and topical pharmaceutical preparations. In topical pharmaceutical formulations, cetostearyl alcohol will increase the viscosity and act as an emulsifier in both water-in-oil and oil-in-water emulsions. Cetostearyl alcohol will stablize an emulsion and also act as a co-emulsifier, thus decreasing the total amount of surfactant required to form a stable emulsion. Cetostearyl alcohol is also used in the preparation of nonaqueous creams and sticks, and in nonlathering shaving creams.(1) Research articles have been published in which cetostearyl alcohol has been used to control or slow the dissolution rate of tablets or microspheres containing water-soluble drugs,(2–5) or poorly watersoluble drugs,(6–8) as well as to stabilize amorphous systems.(9) In combination with other surfactants, cetostearyl alcohol forms emulsions with very complex microstructures. These microstructures can include liquid crystals, lamellar structures, and gel phases.(10–21)
Cetostearyl alcohol occurs as white or cream-colored unctuous masses, flakes, pellets or granules. It has a faint, characteristic sweet odor. On heating, cetostearyl alcohol melts to a clear, colorless or pale yellow-colored liquid free of suspended matter.
See Table I
Boiling point 300-3608C (degradation temperature) Density (bulk) 0.8 g/cm3 at 208C. NIR spectra see Figure 1. Solubility Soluble in ethanol (95%), ether, and oil; practically insoluble in water
Cetostearyl alcohol is stable under normal storage conditions. Cetostearyl alcohol should be stored in a well-closed container in a cool, dry place.
Incompatible with strong oxidizing agents and metal salts.
Cetostearyl alcohol is prepared by the reduction of the appropriate fatty acids from vegetable and animal sources. Cetostearyl alcohol can also be prepared directly from hydrocarbon sources
Cetostearyl alcohol is mainly used in topical pharmaceutical formulations and topical cosmetic formulations. Cetostearyl alcohol is generally regarded as a nontoxic material.(22) Although it is essentially nonirritating, sensitization reactions to cetostearyl, cetyl, and stearyl alcohols(23–28) have been reported. Gamma radiation has been shown to be feasible for sterilization of petrolatum containing cetostearyl alcohol resulting in low levels of radiolysis products, which are of low toxicity.(29)
Observe normal precautions appropriate to the circumstances and quantity of material handled. Eye protection and gloves are recommended. Cetostearyl alcohol is flammable and on combustion may produce fumes containing carbon monoxide.
Accepted as an indirect food additive and as an adhesive and a component of packaging coatings in the USA. Included in the FDA Inactive Ingredients Database (oral tablets; topical emulsions, lotions, ointments; vaginal suppositories). Included in nonparenteral medicines licensed in the UK. Included in the Canadian List of Acceptable Non-medicinal Ingredients
Anionic emulsifying wax; cetyl alcohol; sodium lauryl sulfate; stearyl alcohol.
The composition of cetostearyl alcohol from different sources may vary considerably. The composition of the minor components, typically straight-chain and branched-chain alcohols, varies greatly depending upon the source, which may be animal, vegetable, or synthetic. This has been reported in the literature to impart differences in emulsification behavior, particularly with respect to emulsion consistency or stability.(19–21) The PhEur 6.2 contains specifications for cetostearyl alcohol, emulsifying Type A, and Type B, respectively. Each contains at least 7% surfactant, with Type A containing sodium cetostearyl sulfate and Type B containing sodium lauryl sulfate. See also Wax, Anionic Emulsifying. The EINECS number for cetostearyl alcohol is 267-008-6.