Acetylcysteine Solution
» Acetylcysteine Solution is a sterile solution of Acetylcysteine in water, prepared with the aid of Sodium Hydroxide. It contains not less than 90.0 percent and not more than 110.0 percent 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 10 mL in a suitable beaker, and adjust to a pH of about 2 (pH indicator paper) using 3 N hydrochloric acid. Add up to 2 g of finely powdered sodium chloride, in two portions of about 200 mg each initially, and then in smaller portions (about 25 mg), 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 3 N hydrochloric acid, and stir until the precipitate forms.] Allow to stand at room temperature for 15 minutes, and collect the residue by suction filtration: the acetylcysteine so obtained, after being dried as directed in the test for Loss on drying under Acetylcysteine, responds to the Identification test under Acetylcysteine.
Sterility 71: meets the requirements.
pH 791: between 6.0 and 7.5.
Mobile phase, Internal standard solution, Standard preparation, and Chromatographic system— Proceed as directed in the Assay under Acetylcysteine.
Assay preparation— Pipet a volume of Solution, equivalent to about 1000 mg of acetylcysteine, into a 100-mL volumetric flask, dilute with sodium bisulfite solution (1 in 2000) to volume, and mix. Pipet 10.0 mL of this solution and 10.0 mL of Internal standard solution into a 200-mL volumetric flask, dilute with sodium metabisulfite solution (1 in 2000) to volume, and mix.
Procedure— Proceed as directed for Procedure in the Assay under Acetylcysteine. Calculate the quantity, in mg, of C5H9NO3S in each mL of the Solution taken by the formula:
2000(C/V)(RU / RS)
in which C is the concentration, in mg per mL, of USP Acetylcysteine RS in the Standard preparation; V is the volume, in mL, of Solution taken; and RU and RS are the ratios of the peak response of acetylcysteine to that of dl-phenylalanine obtained from the Assay preparation and the Standard preparation, respectively.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Clydewyn M. Anthony, Ph.D.
(MDCCA05) Monograph Development-Cough Cold and Analgesics
Reference Standards Lili Wang, Technical Services Scientist
71 Radhakrishna S Tirumalai, Ph.D.
Senior Scientist
(MSA05) Microbiology and Sterility Assurance
USP32–NF27 Page 1424
Pharmacopeial Forum: Volume No. 27(3) Page 2503
Chromatographic Column—
Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.