Myristic Acid

Basic Information

Name: Myristic Acid

CAS No: Tetradecanoic acid [544-63-8]

Functional Categories

Emulsifying agent Skin penetrant Tablet and capsule lubricant

1. Nonproprietary Names

None adopted.

2. Synonyms

Edenor C14 98-100; n-tetradecanoic acid; 1-tridecanecarboxylic acid.

3. Chemical Name & CAS Registry

Tetradecanoic acid [544-63-8]

4. Empirical Formula & Molecular Weight

C14H28O2 228.37

5. Structural Formula

6. Applications

Myristic acid is used in oral and topical pharmaceutical formulations. Myristic acid has been evaluated as a penetration enhancer in melatonin transdermal patches in rats(1) and bupropion formulations on human cadaver skin.(2) Further studies have assessed the suitability of myristic acid in oxymorphone formulations(3) and clobetasol 17-propionate topical applications.(4) Furthermore, polyvinyl alcohol substituted with myristic acid (as well as other fatty acids) at different substitution degrees has been used for the preparation of biodegradable microspheres containing progesterone or indomethacin.

7. Description

Myristic acid occurs as an oily white crystalline solid with a faint odor.

8. Pharmacopeial Specifications

See Section 18.

9. Typical Properties

Boiling point 326.28C Flash point >1108C Melting point 54.58C Solubility Soluble in acetone, benzene, chloroform, ethanol (95%), ether, and aromatic and chlorinated solvents; practically insoluble in water. Specific gravity 0.860–0.870

10. Stability & Storage

The bulk material should be stored in a well-closed container in a cool, dry, place.

11. Incompatibilities

Myristic acid is incompatible with strong oxidizing agents and bases.

12. Method of Manufacture

Myristic acid occurs naturally in nutmeg butter and in most animal and vegetables fats. Synthetically, it may be prepared by electrolysis of methyl hydrogen adipate and decanoic acid or by Maurer oxidation of myristyl alcohol.

13. Safety

Myristic acid is used in oral and topical pharmaceutical formulations and is generally regarded as nontoxic and nonirritant at the levels employed as an excipient. However, myristic acid is reported to be an eye and skin irritant at high levels and is poisonous by intravenous administration. Mutation data have also been reported.(6) LD50 (mouse, IV): 0.043 g/kg(6) LD50 (rat, oral): >10 g/kg

14. Handling Precautions

Observe normal precautions appropriate to the circumstances and quantity of the material handled. Acrid smoke and irritating fumes are emitted when myristic acid is heated to decomposition.

15. Regulatory Status

GRAS listed. Included in the FDA Inactive Ingredients Database (oral capsules). Included in nonparenteral medicines licensed in the UK

16. Related Substances

Lauric acid; myristyl alcohol; palmitic acid; potassium myristate; sodium myristate; stearic acid.Potassium myristate Empirical formula C14H28O2K Molecular weight 267.52 CAS number [13429-27-1] Comments Potassium myristate is used as a surfactant and emulsifying agent in pharmaceutical formulations. The EINECS number for potassium myristate is 236-550-5. Sodium myristate Empirical formula C14H28O2Na Molecular weight 251.41 CAS number [822-12-8] Comments Sodium myristate is used as an emulsifying agent in pharmaceutical formulations. The EINECS number for sodium myristate is 212-487-9.

17. Comments

Although not included in any pharmacopeias, a specification for myristic acid is contained in the Food Chemicals Codex (FCC) and in the Japanese Pharmaceutical Excipients (JPE); see Table I. The EINECS number for myristic acid is 208-875-2. The PubChem Compound ID (CID) for myristic acid is 11005.