Stavudine for Oral Solution
» Stavudine for Oral Solution, when reconstituted as directed in the labeling, yields a 1 mg per mL solution that contains not less than 90.0 percent and not more than 110.0 percent of the labeled amount of stavudine (C10H12N2O4). It may contain suitable flavors, preservatives, sweeteners, and stabilizers.
Packaging and storage Preserve in tightly closed containers, protected from excessive moisture. Store at controlled room temperature. After constitution, store the Stavudine for Oral Solution in tightly closed containers under refrigeration. Discard unused portion after 30 days.
Labeling The label contains directions for constitution of the powder and states the equivalent amount of C10H12N2O4 in a given volume of the Stavudine for Oral Solution obtained after constitution.
Identification The retention time of the major peak in the chromatogram of the Assay preparation corresponds to that in the chromatogram of the Standard preparation, as obtained in the Assay.
Deliverable volume 698: meets the requirements.
pH 791: between 5 and 7 when constituted as directed in the labeling.
Water, Method I 921: not more than 2.0%.
Related compounds [noteAll testing solutions must be prepared immediately prior to use and remain refrigerated until use.]
Solution A, Solution B, Resolution solution, and Chromatographic system Proceed as directed in the Assay.
Standard solution Prepare as directed for Standard preparation in the Assay.
Test solution Prepare as directed for Assay preparation.
Procedure Noting the retention times of the impurities relative to that of stavudine, calculate the percentage of all other impurities in the portion of Stavudine for Oral Solution taken by the formula:
100(Fri / rs)in which F is the relative response factor and is equal to 0.69 for thymine (relative retention time of about 0.24) and equal to 1.0 for all other peaks; ri is the peak area response of each impurity obtained from the Test solution; and rs is the sum of the area responses of all the sample-related peaks in the chromatogram including that of the main stavudine peak: not more than 1.0% of thymine is found, not more than 0.2% of any other individual impurity is found, and not more than 1.5% of total impurities is found.
Assay [noteAll testing solutions must be prepared immediately prior to use and remain refrigerated until use.]
25 mM Ammonium acetate Dissolve 1.93 g of ammonium acetate in about 900 mL of water in a 1000-mL volumetric flask. Dilute with water to volume, and mix.
Solution A Prepare a filtered and degassed mixture of 25 mM Ammonium acetate and methanol (94:6).
Solution B Prepare a filtered and degassed mixture of 25 mM Ammonium acetate and methanol (1:1).
Resolution solution Prepare a solution in water of thymidine and thymine containing 2.5 µg of each per mL.
Standard preparation Prepare a solution of USP Stavudine RS in water having a concentration of 0.1 mg per mL.
Assay preparation Transfer to a suitable volumetric flask an accurately measured volume of Stavudine for Oral Solution, constituted as directed in the labeling, and dilute quantitatively, and stepwise if necessary, with water to obtain a solution having a concentration of 0.1 mg of stavudine per mL.
Chromatographic system (see Chromatography 621) The liquid chromatograph is equipped with a 268-nm detector and a 4.6-mm × 3.3-cm column that contains packing L1 and a 4-mm × 20-mm guard column (L1). The flow rate is about 1 mL per minute. The chromatograph is programmed as follows.
Procedure Separately inject equal volumes (about 20 µL) of the Standard preparation and the Assay preparation into the chromatograph, record the chromatograms, and measure the areas for the major peaks. Calculate the quantity, in mg, of stavudine (C10H12N2O4) in each mL of Stavudine for Oral Solution taken by the formula:
(L/D)(C)(rU / rS)in which L is the labeled quantity, in mg, of stavudine (C10H12N2O4) in each mL of the Stavudine for Oral Solution; D is the concentration, in mg, of stavudine per mL of the Assay preparation, based on the labeled quantity of stavudine in the portion of Stavudine for Oral Solution taken; C is the concentration, in mg per mL, of USP Stavudine RS in the Standard preparation; and rU and rS are the peak area responses obtained from the Assay preparation and the Standard preparation, respectively.
Auxiliary Information Please check for your question in the FAQs before contacting USP.Chromatographic Column
USP32NF27 Page 3600Pharmacopeial Forum: Volume No. 30(3) Page 937
Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.