Acetylcysteine Solution
»Acetylcysteine Solution is a sterile solution of Acetylcysteine in water,prepared with the aid of Sodium Hydroxide.It contains not less than 90.0percent and not more than 110.0percent of the labeled amount of acetylcysteine (C5H9NO3S).
Packaging and storage— Preserve in single-unit or multiple-unit tight containers that effectively exclude oxygen,and store at controlled room temperature.
Identification— Place about 10mLin a suitable beaker,and adjust to a pHof about 2(pHindicator paper)using 3Nhydrochloric acid.Add up to 2g of finely powdered sodium chloride,in two portions of about 200mg each initially,and then in smaller portions (about 25mg),stirring after each addition until the sodium chloride dissolves and a precipitate is formed.[NOTE—The precipitate appears as a very fine powder,and the solution turns cloudy.If no precipitate forms,add an additional drop of 3Nhydrochloric acid,and stir until the precipitate forms.]Allow to stand at room temperature for 15minutes,and collect the residue by suction filtration:the acetylcysteine so obtained,after being dried as directed in the test for Loss on dryingunder Acetylcysteine,responds to the Identificationtest under Acetylcysteine.
Sterility á71ñ: meets the requirements.
pHá791ñ: between 6.0and 7.5.
Assay—
Mobile phase,Internal standard solution,Standard preparation,and Chromatographic system— Proceed as directed in the Assayunder Acetylcysteine.
Assay preparation— Pipet a volume of Solution,equivalent to about 1000mg of acetylcysteine,into a 100-mLvolumetric flask,dilute with sodium bisulfite solution (1in 2000)to volume,and mix.Pipet 10.0mLof this solution and 10.0mLof Internal standard solutioninto a 200-mLvolumetric flask,dilute with sodium metabisulfite solution (1in 2000)to volume,and mix.
Procedure— Proceed as directed for Procedurein the Assayunder Acetylcysteine.Calculate the quantity,in mg,of C5H9NO3Sin each mLof the Solution taken by the formula:
2000(C/V)(RU/RS),
in which Cis the concentration,in mg per mL,of USP Acetylcysteine RSin the Standard preparation;Vis the volume,in mL,of Solution taken;and RUand RSare the ratios of the peak response of acetylcysteine to that of DL-phenylalanine obtained from the Assay preparationand the Standard preparation,respectively.
Auxiliary Information— Staff Liaison:Clydewyn M.Anthony,Ph.D.,Scientist
Expert Committee:(PA2)Pharmaceutical Analysis 2
USP28–NF23Page 47
Pharmacopeial Forum:Volume No.27(3)Page 2503
Phone Number:1-301-816-8139