Name: Tricaprylin
CAS No: 1,3-Di(octanoyloxy)propan-2-yl octanoate [538-23-8]
None adopted.
Caprylic acid, 1,2,3-propanetriyl ester; caprylic acid triglyceride; Captex 8000; glycerin tricaprylate; glycerol tricaprylate; glycerol trioctanoate; glyceryl tricaprylate; glyceryl trioctanoate; Hest TC; MCT; Miglyol 808; n-octanoic acid glycerol triester; octanoic acid, 1,2,3-propanetriyl ester; Panasate 800; Rofetan GTC; tricaprilin; tricapryloglycerol; tricaprylylglycerin; trioctanoin; trioctonolglycerol.
1,3-Di(octanoyloxy)propan-2-yl octanoate [538-23-8]
C27H50O6 470.70
Tricaprylin is used in pharmaceutical preparations as a neutral carrier, absorption promoter, and solubilizer for active drugs. It has been used as an oily phase to prepare water-in-oil-in-water multiple emulsions for incorporating water-soluble drugs such as cefadroxil, cephradine, 4-aminoantipyrine, and antipyrine,(1) and also for obtaining stable microcapsules.(2) Tricaprylin acts as a vehicle for topical creams and lotions, and cosmetic preparations. It is used as a penetration-enhancing lipid base with excellent emollient and skin-smoothing properties. Owing to its non-greasy components and low viscosity, it has very good spreadability. In spite of being skin-permeable, tricaprylin does not obstruct natural skin respiration, and hence it is used in baby oils, massage oils, and face masks. It is an excellent dispersant, and acts as a solubilizer, wetting agent and binder in color cosmetics. Being readily miscible with natural oils and surfactants, tricaprylin is used as the fat component in two-phase foam baths. It is used in sunscreen creams and oils because of its compatibility with organic and inorganic filter agents. It is also used as a fixative for perfumes/fragrances.
Tricaprylin occurs as a clear, colorless to pale-yellow liquid. It forms crystals from acetone/ethanol (95%). Tricaprylin is odorless. See also Table I.
Acid value 40.1 for Captex 8000; 40.1 for Miglyol 808; 40.1 for Rofetan GTC. Ash 0.1% for Rofetan GTC Boiling point 2338C at 133.3 Pa (1 mmHg) Cloud point 5.08C for Rofetan GTC Color 4150.0 (Hazen color index) for Captex 8000; 450.0 (Hazen color index) for Miglyol 808; 450.0 (Hazen color index) for Rofetan GTC. Density 0.94–0.96 g/cm3 for Rofetan GTC at 208C Fatty acid distribution see Table II. Flash point 2468C (open cup) for Captex 8000 Heavy metals 10 mg/kg for Rofetan GTC HLB value 7.0 for Hest TC Hydroxyl value 40.5 for Miglyol 808; 40.5 for Rofetan GTC. Iodine number 40.3 for Miglyol 808; 40.3 for Rofetan GTC. Melting point 9–108C Moisture content 40.1% w/w for Captex 8000; 40.1% w/w for Miglyol 808; 40.1% w/w for Rofetan GTC. Partition coefficient log Pow (octanol : water) = 9.20(3) Peroxide value 40.1 for Miglyol 808; 40.1 for Rofetan GTC. Refractive index 1.447 for Rofetan GTC at 208C Saponification value 345–360 for Captex 8000; 340–370 for Miglyol 808; 340–370 for Rofetan GTC. Solubility Miscible with most organic solvents including ethanol (95%). Captex 8000 is insoluble in water. Specific gravity 0.94 for Captex 8000 at 258C Vapor pressure <133.3 Pa (<1mmHg) for Captex 8000 at 258C Viscosity (dynamic) 23–29 mPa s (23–29 cP) for Miglyol 808 at 208C; 23–29 mPa s (23–29 cP) for Rofetan GTC at 208C. Viscosity (kinematic) 20.9mm2/ s (20.9 cSt) for Captex 8000 at 258C
Tricaprylin is classified as a stable compound. It has high stability against oxidation and is not heat sensitive. Even in hot climates cooling is not necessary. However, exposure to high temperatures near the flash point (2468C) should be avoided. Owing to its very low water content, it is not sensitive to hydrolytic and microbial splitting. Although polymerization of tricaprylin will not occur, it is reported to decompose into carbon monoxide and carbon dioxide. Tricaprylin should be stored in well-closed containers, protected from light, in a dry place at ambient temperature. High-density polyethylene, polypropylene, metal (aluminum), and glass are suitable for packaging. Some plastics, especially those containing plasticizers, can become brittle or expand in the presence of tricaprylin. Polystyrene and polyvinyl chloride are not suitable for its storage. Tricaprylin has a high tendency to migrate, and therefore care should be taken when selecting seal-closure elastomer material.
Tricaprylin is incompatible with strong oxidizing agents.
Tricaprylin is a triglyceride manufactured by esterification of caprylic acid and glycerin.
Tricaprylin is used in pharmaceutical and cosmetic formulations. The Cosmetic Ingredient Review (CIR) Expert Panel found that dermal application of tricaprylin has not been associated with significant irritation in rabbit skin.(2) However, as a penetration enhancer, tricaprylin may allow other chemicals to penetrate deeper into the skin, increasing their concentration so that they may reach the bloodstream. Ocular exposures of tricaprylin were found to be only mildly irritating to rabbit eyes.(4) Little or no acute, subchronic, or chronic oral toxicity was observed in animal studies unless levels approached a significant percentage of caloric intake.(4) Subcutaneous injections of tricaprylin in rats over a period of 5 weeks caused a granulomatous reaction.(4) Tricaprylin has not been found to be teratogenic in rats, mice, or hamsters, but some reproductive effects have been seen in rabbits.(4) Dose-related central nervous system toxicity in dogs has also been observed.(5) LD50 (mouse, IP): >27.8 g/kg(6) LD50 (mouse, IV): 3.7 g/kg(7) LD50 (mouse, oral): 29.6 g/kg(7) LD50 (mouse, SC): >27.8 g/kg(6) LD50 (rat, IP): 0.05 g/kg(7) LD50 (rat, IV): 4 g/kg(6) LD50 (rat, oral): 33.3 g/kg(7)
Observe normal precautions appropriate to the circumstances and quantity of the material handled. Use of a mask and/or respirator is recommended. When heated to decomposition, tricaprylin emits acrid smoke and irritating fumes. Ventilation is recommended to control dust or fumes from the heated material. Chemical splash goggles are recommended for eye protection, and neoprene-type gloves are also recommended.
Included in the FDA Inactive Ingredients Database (epidural injections).
Glyceryl triisooctanoate; medium-chain triglycerides. Glyceryl triisooctanoate Empirical formula C27H50O6 Molecular weight 470.68 CAS number [7360-38-5] Synonyms Glyceryl tris-2-ethylhexanoate Residue on ignition 40.5% Specific gravity 0.945–0.950 Comments A clear, colorless to pale yellow, oily liquid; odorless. Miscible with ethanol, 2-propanol, and diethyl ether; practically insoluble in water. Listed in JPE 2004.(8)
Although it is not currently included in the pharmacopeias, a specification for tricaprylin is included in the Japanese Pharmaceutical Excipients Directory (JPED); see Table III. It is included in the Cosmetics Ingredient Review (CIR) Category 1 and Category 37 as safe for use in cosmetics.(9) Tricaprylin has been used as a skin permeation enhancer in studies of transdermal drug delivery systems. Studies have shown improved skin permeability of various drugs with different lipophilicity with tricaprylin/ethanol (60/40) lipophilic binary vehicle.(10–16) Tricaprylin has also been used as the oily phase to fabricate ‘hairy’ colloidosomes(17) and colloidosome microcapsules( 18) for drug delivery applications. Tricaprylin/glycerol monostearate/water systems are increasingly being used as mesophases existing in biological systems for study of drug behavior across membranes as they have structural resemblance to human membranes.(19,20) Reverse hexagonal liquidcrystalline structures composed of monoolein/tricaprylin/water have been demonstrated to solubilize large quantities of ciclosporin A and penetration enhancers.(21) Tricaprylin is also used as an oily phase in various model emulsions which are used as substrates in food and agricultural research(22) or for studying the stability and rheology of oil-in-water emulsions.(23) Tricaprylin has been reported as a microemulsion for oral delivery of low-molecularweight heparin conjugates,(24) and an intramuscular injection of triolein/tricaprylin multivesicular liposome formulation for the sustained delivery of breviscapine has been reported.(25) The EINECS number of tricaprylin is 208-686-5. The PubChem Compound ID for tricaprylin is 10850.
