(C9H7NO)2·H2SO4 388.40

8-Quinolinol sulfate (2:1)(salt).
8-Quinolinol sulfate (2:1)(salt) [134-31-6].

Packaging and storage— Preserve in well-closed containers.

USP Reference standards á11ñ— USP Oxyquinoline Sulfate RS.

Identification—

Water,Method Iá921ñ: between 4.0%and 6.0%.

Residue on ignition á281ñ: not more than 0.3%.

Heavy metals,Method IIá231ñ: 20µg per g.

Organic volatile impurities,Method Iá467ñ: meets the requirements.

Assay— Transfer about 100mg of Oxyquinoline Sulfate,accurately weighed,to an iodine flask,add 30mLof glacial acetic acid,25.0mLof 0.1Nbromine VS,10mLof potassium bromide solution (3in 20),and 10mLof hydrochloric acid,immediately insert the stopper,mix,and allow to stand for 15minutes,protected from light.Quickly add 10mLof potassium iodide solution (1in 10)and 100mLof water,taking precautions against the escape of bromine vapor,at once insert the stopper,and shake the mixture thoroughly.Remove the stopper,and rinse it and the neck of the flask with a small quantity of water so that the washing flows into the flask.Shake the mixture thoroughly,and titrate the liberated iodine with 0.1Nsodium thiosulfate VS,adding 3mLof starch TSas the endpoint is approached.Perform a blank determination (see Residual Titrationsunder Titrimetry á541ñ).Each mLof 0.1Nbromine is equivalent to 4.855mg of (C9H7NO)2·H2SO4.

Expert Committee:(EMC)Excipients:Monograph Content

USP28–NF23Page 3045

Phone Number:1-301-816-8262