Ganciclovir Oral Suspension
» Ganciclovir Oral Suspension contains not less than 90.0 percent and not more than 110.0 percent of the labeled amount of ganciclovir (C9H13 N5O4). Prepare Ganciclovir Oral Suspension 100 mg per mL as follows (see Pharmaceutical CompoundingNonsterile Preparations 795):
If using Ganciclovir Capsules, empty the contents of the Capsules providing the appropriate amount of drug into a suitable mortar, or add Ganciclovir powder to the mortar. Add sufficient Vehicle to wet the powder, and work to a smooth paste. Add additional Vehicle to about half the final volume, and transfer the contents of the mortar to a calibrated bottle. Using additional Vehicle, rinse out the mortar, and transfer the contents, stepwise and quantitatively, to bring to final volume, and mix well.
[CautionAvoid skin contact or inhalation of ganciclovir by using protective gloves and a fume hood or surgical mask. ]
Packaging and storage Preserve in tight, light-resistant containers. Store at controlled room temperature.
Labeling Label it to state that it is to be well shaken before use, and to state the beyond-use date.
USP Reference standards 11
pH 791: between 4.0 and 5.0.
Beyond-use date: 90 days after the day on which it was compounded.
25 mM Monobasic sodium phosphate buffer Prepare a 25 mM monobasic sodium phosphate solution, and adjust with phosphoric acid to a pH of 2.5.
Mobile phase Prepare a solution of 25 mM Monobasic sodium phosphate buffer and acetonitrile (97.5:2.5). Filter, and degas. Make adjustments if necessary (see System Suitability under Chromatography 621).
Sample diluent Prepare a solution of water, acetonitrile, and methanol (80:15:5).
Internal standard solution Prepare a 4 mg per mL aqueous solution of hypoxanthine.
Standard stock preparation Dissolve an accurately weighed quantity of USP Ganciclovir RS in water to obtain a concentration of about 1.0 mg per mL.
Standard preparation Transfer an appropriate volume of Standard stock preparation to a suitable container, and add an appropriate volume of Internal standard solution to obtain a solution having known concentrations of 6 µg per mL and 4 µg per mL, respectively.
Assay preparation Transfer about 1 mL of Oral Suspension from each bottle to a plastic weighing cup, and weigh to determine density. [noteThe exact volume of Oral Suspension taken from each bottle is calculated by the suspension density. ] Transfer the suspension to a 100-mL volumetric flask, and add about 50 mL of water. Place the volumetric flask on a mechanical shaker for 30 minutes, and then dilute with water to volume. Transfer 0.6 mL from this solution and 1 mL of the Internal standard solution to a 100-mL volumetric flask, and dilute with water to volume.
Chromatographic system (see Chromatography 621) The liquid chromatograph is equipped with a 254-nm detector and a 4.6-mm × 10-cm analytical column that contains 5-µm packing L1. The flow rate is about 1.5 mL per minute. Chromatograph the Standard preparation, and record the peak responses as directed for Procedure: the relative retention times are 1.0 for ganciclovir and 0.75 for hypoxanthine; and the relative standard deviation for replicate injections is not more than 1.5%.
Procedure Separately inject equal volumes (about 10 µL) of the Standard preparation and the Assay preparation into the chromatograph, record the chromatograms, and measure the responses for the major peaks. Calculate the quantity, in mg, of ganciclovir (C9H13N5O4) in the volume of Oral Suspension taken by the formula:
100(C/V)(RU / RS)in which C is the concentration, in mg per mL, of USP Ganciclovir RS in the Standard preparation; V is the volume, in mL, of Oral Suspension taken; and RU and RS are the peak response ratios of the analyte peak to the internal standard peak obtained from the Assay preparation and the Standard preparation, respectively.
Auxiliary Information Please check for your question in the FAQs before contacting USP.
USP35NF30 Page 3319Pharmacopeial Forum: Volume No. 32(1) Page 113