Packaging and storage— Preserve in tight containers,and avoid freezing.

Identification— The addition of acetic acid to it produces effervescence,and the resulting solution,after being boiled,responds to the tests for Calcium á191ñ.

Microbial limits á61ñ— Its total aerobic microbial count does not exceed 100cfu per mL,and it meets the requirements of the test for absence of Escherichia coliand Pseudomonas aeruginosa.

pHá791ñ between 7.5and 8.7.

Other requirements— It meets the requirements of the tests for Limit of fluoride,Arsenic,Lead,and Heavy metalsunder Calcium Carbonate,portions of Oral Suspension adequate to provide quantities of calcium carbonate equivalent to the stated amounts of test specimen being used.

Assay— Transfer an accurately measured quantity of Oral Suspension,previously shaken in its original container,equivalent to about 1g of calcium carbonate,to a beaker with the aid of 25mLof water,and add 20mLof 1Nhydrochloric acid.Heat on a steam bath for 30minutes,allow to cool,transfer with the aid of water to a 100-mLvolumetric flask,dilute with water to volume,mix,and filter.Transfer 20.0mLof the filtrate to a suitable container,dilute with water to 100mL,add 15mLof 1Nsodium hydroxide,5mLof triethanolamine,and 100mg of hydroxy naphthol blue,and titrate with 0.05Medetate disodium VSuntil the solution is deep blue.Each mLof 0.05Medetate disodium is equivalent to 5.004mg of calcium carbonate (CaCO3).

Expert Committee:(DSN)Dietary Supplements:Non-Botanicals

USP28–NF23Page 320

Phone Number:1-301-816-8389