U.S. PHARMACOPEIA

Search USP29  
Tobramycin for Injection
» Tobramycin for Injection contains an amount of Tobramycin Sulfate equivalent to not less than 90.0 percent and not more than 115.0 percent of the labeled amount of tobramycin (C18H37N5O9).
Packaging and storage— Preserve in Containers for Sterile Solids as described under Injections 1.
Constituted solution— At the time of use, it meets the requirements for Constituted Solutions under Injections 1.
Identification—
A: It responds to the Identification tests under Tobramycin.
B: It responds to the tests for Sulfate 191.
Bacterial endotoxins 85 It contains not more than 2.00 USP Endotoxin Units per mg of tobramycin.
Sterility 71 It meets the requirements when tested as directed for Membrane Filtration under Test for Sterility of the Product to be Examined, 6 g being used if it is not packaged for dispensing.
pH 791: between 6.0 and 8.0, in a solution containing 40 mg per mL (or, where packaged for dispensing, in the solution constituted as directed in the labeling).
Water, Method I 921: not more than 2.0%.
Particulate matter 788: meets the requirements for small-volume injections.
Residual solvents 467: meets the requirements.
(Official January 1, 2007)
Other requirements— It meets the requirements for Residue on ignition and Heavy metals under Tobramycin. It meets also the requirements for Uniformity of Dosage Units 905 and Labeling under Injections 1.
Assay—
Mobile phase, 2,4-Dinitrofluorobenzene reagent, Tris(hydroxymethyl)aminomethane reagent, Standard preparation, Derivatization procedure, Resolution solution, and Chromatographic system— Proceed as directed in the Assay under Tobramycin.
Assay preparation 1 (where it is represented as being in a single-dose container)—Constitute a container of Tobramycin for Injection in a volume of water, accurately measured, corresponding to the volume of diluent specified in the labeling. Withdraw all of the withdrawable contents, using a suitable hypodermic needle and syringe, and dilute quantitatively with water to obtain a solution containing the equivalent of about 0.2 mg of tobramycin (C18H37N5O9) per mL.
Assay preparation 2 (where the label states the quantity of tobramycin in a given volume of constituted solution)—Constitute a container of Tobramycin for Injection in a volume of water, accurately measured, equivalent to the volume of diluent specified in the labeling. Dilute an accurately measured volume of the constituted solution quantitatively with water to obtain a solution containing about 0.2 mg of tobramycin (C18H37N5O9) per mL.
Procedure— Proceed as directed for Procedure in the Assay under Tobramycin. Calculate the quantity, in mg, of tobramycin (C18H37N5O9) withdrawn from the container, or in the portion of constituted solution taken by the formula:
(L / D)(CE / 1000)(rU / rS),
in which L is the labeled quantity, in mg, of tobramycin (C18H37N5O9) in the container, or in the volume of constituted solution taken; D is the concentration, in mg of tobramycin per mL, of Assay preparation 1 or Assay preparation 2, based on the labeled quantity in the container or in the volume of constituted solution taken, respectively, and the extent of dilution; and the other terms are as defined therein.
Auxiliary Information— Staff Liaison : Brian D. Gilbert, Ph.D., Scientist
Expert Committee : (MDANT05) Monograph Development-Antibiotics
USP29–NF24 Page 2160
Phone Number : 1-301-816-8223