Tobramycin Sulfate
(C18H37N5O9)2·5H2SO4 1425.45

D-Streptamine,O-3-amino-3-deoxy-a-D-glucopyranosyl-(1®6)-O-[2,6-diamino-2,3,6-tridoexy-a-D-ribo-hexopyranosyl-(1®4)]-2-deoxy-,sulfate (2:5)(salt).
O-3-Amino-3-deoxy-a-D-glucopyranosyl-(1®4)-O-[2,6-diamino-2,3,6-trideoxy-a-D-ribo-hexopyranosyl-(1®6)]-2-deoxy-L-streptamine,sulfate (2:5)(salt) [79645-27-5].
»Tobramycin Sulfate has a potency of not less than 634µg and not more than 739µg of tobramycin (C18H37N5O9)per mg.
Packaging and storage— Preserve in tight containers.
Labeling— Where it is intended for use in preparing injectable dosage forms,the label states that it is sterile or must be subjected to further processing during the preparation of injectable dosage forms.
Identification—
A: It responds to the Identificationtests under Tobramycin.
B: It responds to the tests for Sulfate á191ñ.
pHá791ñ: between 6.0and 8.0,in a solution containing 40mg per mL.
Water,Method Iá921ñ: not more than 2.0%.
Other requirements— It meets the requirements for Residue on ignition,Heavy metals,and Chromatographic purityunder Tobramycin.Where the label states that Tobramycin Sulfate is sterile,it meets the requirements for Sterility Tests á71ñand for Bacterial endotoxinsunder Tobramycin for Injection.Where the label states that Tobramycin Sulfate must be subjected to further processing during the preparation of injectable dosage forms,it meets the requirements for Bacterial endotoxinsunder Tobramycin for Injection.
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 Assayunder Tobramycin.
Assay preparation— Transfer an accurately weighed quantity of Tobramycin Sulfate,equivalent to about 50mg of tobramycin (C18H37N5O9),to a 250-mLvolumetric flask,dissolve in and dilute with water to volume,and mix.
Procedure— Proceed as directed for Procedurein the Assayunder Tobramycin.Calculate the quantity,in µg,of tobramycin (C18H37N5O9)in each mg of the Tobramycin Sulfate taken by the formula:
250(CE/W)(rU/rS),
in which the terms are as defined therein.
Auxiliary Information— Staff Liaison:William W.Wright,Ph.D.,Scientific Fellow
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 1944
Phone Number:1-301-816-8335