»Clove Oil is the volatile oil distilled with steam from the dried flower buds of Syzygium aromaticum(L.)Merr.and L.M.Perry (Fam.Myrtaceae).It contains not less than 85.0percent (v/v)of total phenolic substances,chiefly eugenol (C10H12O2).
Packaging and storage Preserve in well-filled,tight containers,and avoid exposure to excessive heat.
Labeling The label states the Latin binomial name and,following the official name,the part of the plant source from which the article was derived.
Solubility in 70percent alcohol One volume dissolves in 2volumes of 70percent alcohol.
Specific gravity á841ñ: between 1.038and 1.060.
Angular rotation á781Añ It is optically inactive or slightly levorotatory;and the angular rotation is not greater than 1.5.
Refractive index á831ñ: between 1.527and 1.535at 20.
Heavy metals,Method IIá231ñ: 0.004%.
Limit of phenol Shake 1mLof Oil with 20mLof hot water:the water shows not more than a scarcely perceptible acid reaction with blue litmus paper.Cool the mixture,pass the water layer through a wetted filter,and treat the clear filtrate with 1drop of ferric chloride TS:the mixture exhibits only a transient,grayish green color,but not a blue or violet color.
Assay Pipet 10mLof Oil into a suitable cassia flask,the neck of which is graduated from 0mLto 6mLat intervals of 0.1mL.Add 75mLof 1Npotassium hydroxide,shake the mixture for 5minutes,and heat for 10minutes in boiling water,shaking the flask at least 3times during the heating.Remove the flask from the bath,and cool to room temperature.When the liquids have separated completely,add sufficient 1Npotassium hydroxide to raise the lower level of the oily layer within the graduated portion of the neck.After standing for 18hours,the volume of the oily layer does not exceed 1.5mL,indicating the presence in the Oil of not less than 85.0%,by volume,of total phenolic substances.
Auxiliary Information Staff Liaison:Claudia C.Okeke,Ph.D.,Associate Director
Expert Committee:(CRX)Compounding Pharmacy
USP28NF23Page 2989Pharmacopeial Forum:Volume No.27(4)Page 2796