Packaging and storage— Preserve in well-closed containers.

Melting range,Class IIá741ñ: between 62and 65.

Saponification cloud test— Place 3.00g in a round-bottom,100-mLboiling flask fitted with a ground-glass joint.Add 30mLof a solution prepared by dissolving 40g of potassium hydroxide in about 900mLof aldehyde-free alcohol maintained at a temperature not exceeding 15,and then when solution is complete,warming to room temperature and adding aldehyde-free alcohol to make 1000mL.Reflux the mixture gently for 2hours.At the end of this period,open the flask,insert a thermometer into the solution,and place the flask in a container of water at a temperature of 80.Rotate the flask in the bath while both the bath and the solution cool:the solution shows no cloudiness or globule formation before the temperature reaches 65.

Fats or fatty acids,Japan wax,rosin,and soap— Boil 1g for 30minutes with 35mLof 3.5Nsodium hydroxide contained in a 100-mLbeaker,maintaining the volume by the occasional addition of water,and allow the mixture to cool at room temperature for about 2hours:the wax separates,leaving the liquid clear,turbid,or translucent,but not opaque.Filter the cool mixture,and acidify the clear filtrate with hydrochloric acid:the liquid remains clear or shows not more than a slight amount of turbidity or precipitate.

Acid value á401ñ— Warm about 3g,accurately weighed,in a 200-mLflask with 25mLof neutralized dehydrated alcohol until melted,shake the mixture,add 1mLof phenolphthalein TS,and titrate the warm liquid with 0.5Nalcoholic potassium hydroxide VSto produce a permanent,faint pink color:the acid value so obtained is between 17and 24.

Ester value á401ñ— To the solution resulting from the determination of Acid valueadd 25.0mLof 0.5Nalcoholic potassium hydroxide VSand 50mLof aldehyde-free alcohol,reflux the mixture for 4hours,and titrate the excess alkali with 0.5Nhydrochloric acid VS.Perform a blank determination (see Residual Titrationsunder Titrimetry á541ñ).The ester value so obtained is between 72and 79.

Expert Committee:(EMC)Excipients:Monograph Content

USP28–NF23Page 3107

Phone Number:1-301-816-8330