(lee'' voe flox' a sin).
7H-Pyrido[1,2,3-de]-1,4-benzoxazine-6-carboxylic acid, 9-fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-hydrate (2:1), (S)-;
()-(S)-9-Fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-7H-pyrido[1,2,3-de]-1,4-benzoxazine-6-carboxylic acid, hemihydrate [138199-71-0].
Levofloxacin contains NLT 98.5% and NMT 102.0% of C18H20FN3O4, calculated on the anhydrous basis.
• B. The retention time of the major peak of the Sample solution corresponds to that of the Standard solution, as obtained in the Assay.
Solution A: 8.5 g/L of ammonium acetate, 1.25 g/L of cupric sulfate, pentahydrate, and 1.3 g/L of l-isoleucine in water
Mobile phase: Methanol and Solution A (3:7)
Standard solution: 1 mg/mL of USP Levofloxacin RS in Mobile phase
Sample solution: 1 mg/mL of Levofloxacin in Mobile phase
Detector: UV 360 nm
Column: 4.6-mm × 25-cm; 5-µm packing L1
Column temperature: 45
Flow rate: 0.8 mL/min
Injection size: 25 µL
Sample: Standard solution
Tailing factor: 0.51.5
Relative standard deviation: NMT 1.0%
Samples: Standard solution and Sample solution
Calculate the percentage of C18H20FN3O4 in the portion of Levofloxacin taken:
Result = (rU/rS) × (CS/CU) × 100
Acceptance criteria: 98.5%102.0% on the anhydrous basis
• Residue on Ignition 281: NMT 0.2%. Use a platinum crucible.
• Heavy Metals, Method II 231: NMT 10 ppm
Solution A, Mobile phase, Sample solution, and Chromatographic system: Proceed as directed in the Assay.
System suitability solution: 1 mg/mL of USP Levofloxacin RS in Mobile phase
Sensitivity solution: 0.3 µg/mL of USP Levofloxacin RS in Mobile phase
Samples: System suitability solution and Sensitivity solution
Relative standard deviation: NMT 1.0%, System suitability solution
Signal-to-noise ratio: NLT 10, Sensitivity solution
Sample: Sample solution
Calculate the percentage of each individual impurity in the portion of Levofloxacin taken:
Result = (rU/rS) × (1/F) × 100
Individual impurities: See Impurity Table 1.
Total impurities: NMT 0.5%. [NoteDo not include the d-isomer in the calculation for Total impurities. ]
Impurity Table 1
• Optical Rotation, Specific Rotation 781S
Sample solution: 5 mg/mL in Solvent
Acceptance criteria: 92 to 106, at 20
• Water Determination, Method Ia 921: 2.1%2.7%
• Packaging and Storage: Preserve in tight and light-resistant containers. Store at room temperature.
• USP Reference Standards 11
Auxiliary Information Please check for your question in the FAQs before contacting USP.
USP35NF30 Page 3671Pharmacopeial Forum: Volume No. 35(6) Page 1459