Name: Polyoxylglycerides
CAS No: See Table II.
BP: Caprylocaproyl Macrogolglycerides Lauroyl Macrogolglycerides Linoleoyl Macrogolglycerides Oleoyl Macrogolglycerides Stearoyl Macrogolglycerides PhEur: Caprylocaproyl Macrogolglycerides Lauroyl Macrogolglycerides Linoleoyl Macrogolglycerides Oleoyl Macrogolglycerides Stearoyl Macrogolglycerides USP-NF: Caprylocaproyl Polyoxylglycerides Lauroyl Polyoxylglycerides Linoleoyl Polyoxylglycerides Oleoyl Polyoxylglycerides Stearoyl Polyoxylglycerides
Polyoxylglycerides are referred to as macrogolglycerides in Europe; see Table I.
See Table II.
Polyoxylglycerides are mixtures of monoesters, diesters, and triesters of glycerol, and monoesters and diesters of polyethylene glycols (PEG). Caprylocaproyl polyoxylglycerides Mixtures of monoesters, diesters, and triesters of glycerol and monoesters and diesters of polyethylene glycols with mean relative molecular mass between 200 and 400. They are obtained by partial alcoholysis of medium-chain triglycerides using polyethylene glycol or by esterification of glycerin and polyethylene glycol with caprylic (octanoic) acid and capric (decanoic) acid or a mixture of glycerin esters and condensates of ethylene oxide with caprylic acid and capric acid. They may contain free polyethylene glycols. Lauroyl polyoxylglycerides Mixtures of monoesters, diesters, and triesters of glycerol and monoesters and diesters of polyethylene glycols with mean relative molecular mass between 300 and 1500. They are obtained by partial alcoholysis of saturated oils mainly containing triglycerides of lauric (dodecanoic) acid, using polyethylene glycol, or by esterification of glycerol and polyethylene glycol with saturated fatty acids, or by mixing glycerol esters and condensates of ethylene oxide with the fatty acids of these hydrogenated oils. Linoleoyl polyoxylglycerides Mixtures of monoesters, diesters, and triesters of glycerol and monoesters and diesters of polyethylene glycols. They are obtained by partial alcoholysis of an unsaturated oil mainly containing triglycerides of linoleic (cis,cis-9,12-octadecadienoic) acid, using polyethylene glycol with mean relative molecular mass between 300 and 400, or by esterification of glycerol and polyethylene glycol with unsaturated fatty acids, or by mixing glycerol esters and condensates of ethylene oxide with the fatty acids of this unsaturated oil. Oleoyl polyoxylglycerides Mixtures of monoesters, diesters, and triesters of glycerol and monoesters and diesters of polyethylene glycols. They are obtained by partial alcoholysis of an unsaturated oil mainly containing triglycerides of oleic (cis-9- octadecenoic) acid, using polyethylene glycol with mean relative molecular mass between 300 and 400, or by esterification of glycerol and polyethylene glycol with unsaturated fatty acids, or by mixing glycerol esters and condensates of ethylene oxide with the fatty acids of this unsaturated oil. Stearoyl polyoxylglycerides Mixtures of monoesters, diesters, and triesters of glycerol and monoesters and diesters of polyethylene glycols with mean relative molecular mass between 300 and 4000. They are obtained by partial alcoholysis of saturated oils containing mainly triglycerides of stearic (octadecanoic) acid, using polyethylene glycol, or by esterification of glycerol and polyethylene glycol with saturated fatty acids, or by mixture of glycerol esters and condensates of ethylene oxide with the fatty acids of these hydrogenated oils.
Polyoxylglycerides are used as self-emulsifying and solubilizing agents in oral and topical pharmaceutical formulations. They are also used in cosmetic and food products. See also Tables III, IV, V, VI, and VII.
Polyoxylglycerides are inert liquid or semi-solid waxy materials and are amphiphilic in character. Caprylocaproyl polyoxylglycerides are pale-yellow oily liquids. Lauroyl polyoxylglycerides and stearoyl polyoxylglycerides occur as pale-yellow waxy solids. Oleoyl polyoxylglycerides and linoleoyl polyoxylglycerides occur as amber oily liquids, which may give rise to a deposit after prolonged periods at 208C.
See Tables VIII and IX.
Solubility Caprylocaproyl and lauroyl polyoxylglycerides: dispersible in hot water; freely soluble in methylene chloride. Linoleoyl and oleoyl polyoxylglycerides: practically insoluble but dispersible in water; freely soluble in methylene chloride. Stearoyl polyoxylglycerides: dispersible in warm water and warm liquid paraffin; soluble in warm ethanol; freely soluble in methylene chloride. Viscosity Linoleoyl polyoxylglycerides: 70–90 mPa s at 208C, 35 mPa s at 408C for PEG 300. Oleoyl polyoxylglycerides: 75–95 mPa s at 208C, 35 mPa s at 408C for PEG 300
Polyoxylglycerides are very stable and inert. However, preventive measures against the risk of oxidation or hydrolysis may be taken to ensure stability during handling. See Section 15. Polyoxylglycerides should be preserved in their original containers, and exposure to air, light, heat, and moisture should be prevented.
Polyoxylglycerides are obtained by partial alcoholysis of vegetable oils using macrogols, by esterification of glycerol and macrogols with unsaturated fatty acids, or by mixing glycerol esters and condensates of ethylene oxide with the fatty acids of the vegetable oil
Polyoxylglycerides are used in oral and topical pharmaceutical formulations, and also in cosmetics and food products. They are generally regarded as relatively nonirritant and nontoxic materials. Caprylocaproyl polyoxylglycerides: LD50 (rat, oral): >22 ml/(kg day).(59) Lauroyl polyoxylglycerides: LD50 (rat, oral): >2004 mg/(kg day).(60)
Observe normal precautions appropriate to the circumstances and quantities of the material handled (refer to manufacturers’ safety information). Polyoxylglycerides are heterogeneous. Owing to their composition and physical characteristics, semisolid polyoxylglycerides can segregate by molecular weight over time during storage in containers, resulting in a nonhomogenous distribution. In addition, semisolid polyoxylglycerides must be heated to at least 208C above melting point in order to ensure that all crystallization clusters are fully melted. Therefore, it is essential that the entire contents of each container are melted to facilitate sample withdrawal or transfer, ensuring sample homogeneity. For liquid polyoxylglycerides, owing to their composition and physical characteristics, partial crystallization of saturated glycer-ides may be observed after long-term storage. In case of crystallization, heat to 60–708C before use. Polyoxylglycerides are hygroscopic. Only heat in a water bath if the materials are contained in a sealed glass container or are for immediate use. Otherwise, heat in a microwave or convention oven. Avoid exposure to excessive and repeated high temperatures (i.e. above 1008C) and cooling cycles. To ensure stability during handling, and avoid the risk of oxidation or hydrolysis, the following measures should be taken: Risk of oxidation: . minimize aeration of the mixture (avoid use of high-speed homogenizers); . minimize and control the degree of exposure to heat and light; . use a nitrogen blanket. Risk of hydrolysis: . minimize and control relative humidity; . do not heat near a source of humidity (e.g. water bath).
Lauroyl polyoxylglycerides and stearoyl polyoxylglycerides are approved as food additives in the USA. Included in the FDA Inactive Ingredients Database (oral route: capsules, tablets, solutions; topical route: emulsions, creams, lotions; vaginal route: emulsions, creams). Oleyl polyoxylglycerides are included in a topical cream formulation licensed in the UK
See Table XI for EINECS numbers for polyoxylglycerides.