(sef a' zoe lin soe' dee um).
5-Thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, 3-[[(5-methyl-1,3,4-thiadiazol-2-yl)thio]methyl]-8-oxo-7-[[(1H-tetrazol-1-yl)acetyl]amino]-, monosodium salt (6R-trans);
Monosodium (6R,7R)-3-[[(5-methyl-1,3,4-thiadiazol-2-yl)thio]methyl]-8-oxo-7-[2-(1H-tetrazol-1-yl)acetamido]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate [27164-46-1].
Cefazolin Sodium has a potency equivalent to NLT 89.1% and NMT 110.1% of cefazolin sodium (C14H13NaN8O4S3), calculated on the anhydrous basis.
• A. Ultraviolet Absorption 197U
Sample solution: 20 µg/mL in 0.1 M sodium bicarbonate
Acceptance criteria: Meets the requirements
• B. The retention time of the major peak for cefazolin in the Sample solution corresponds to that of the Standard solution, as obtained in the Assay.
• C. Identification TestsGeneral, Sodium 191: Meets the requirements
Buffer A: 0.9 g/L of anhydrous dibasic sodium phosphate and 1.298 g/L of citric acid monohydrate in water
Buffer B: 5.68 g/L of anhydrous dibasic sodium phosphate and 3.63 g/L of monobasic potassium phosphate in water
Mobile phase: Acetonitrile and Buffer A (1:9). Pass through a membrane filter having a 10-µm or finer pore size.
Internal standard solution: 7.5 mg/mL of salicylic acid in methanol and Buffer B (1:9). Dissolve first in methanol, using 10% of the final volume, and dilute with water to volume.
Standard stock solution: 1 mg/mL of USP Cefazolin RS in Buffer B
Standard solution: 50 µg/mL of cefazolin from the Standard stock solution and 0.4 mg/mL of salicylic acid from the Internal standard solution in Buffer B
Sample stock solution: 1 mg/mL of Cefazolin Sodium in Buffer B
Sample solution: 50 µg/mL of cefazolin sodium from the Sample stock solution and 0.4 mg/mL of salicylic acid from the Internal standard solution in Buffer B
Detector: UV 254 nm
Column: 4.0-mm × 30-cm; 10-µm packing L1
Flow rate: 2 mL/min
Injection size: 10 µL
Sample: Standard solution
[NoteThe relative retention times for salicylic acid and cefazolin are about 0.7 and 1.0, respectively. ]
Resolution: NLT 4.0 between the analyte and the internal standard peaks
Column efficiency: NLT 1500 theoretical plates
Tailing factor: NMT 1.5
Relative standard deviation: NMT 2.0%
Samples: Standard solution and Sample solution
Calculate the percentage of cefazolin sodium (C14H13N8NaO4S3) in the portion of Cefazolin Sodium taken:
Result = (RU/RS) × (CS/CU) × (Mr1/Mr2) × 100
Acceptance criteria: 89.1%110.1% on the anhydrous basis
• Organic Impurities
[NoteUse the Sample solution immediately after preparation. ]
Buffer A: 6.8 g/L of monobasic potassium phosphate
Solution B: 6.8 g/L of monobasic potassium phosphate adjusted with 10% sodium hydroxide to a pH of 6.8 before final dilution
Solution C: Acetonitrile and Buffer A (1:1)
Mobile phase: See Table 1.
Blank: Use Solution B.
System suitability stock solution: 2 mg/mL of USP Cefazolin RS in 0.05 M sodium hydroxide. Set the solution aside at room temperature for 5 min. [NoteThe cefazolin epimer is formed upon treatment of cefazolin with sodium hydroxide. ]
System suitability solution: System suitability stock solution and Buffer B (1:24)
Standard solution: 25 µg/mL of USP Cefazolin RS in Solution B
Sample solution: 2.5 mg/mL of Cefazolin Sodium in Solution B
Detector: UV 210 and 254 nm
Column: 4.6-mm × 25-cm; 5-µm packing L1
Flow rate: 1.5 mL/min
Injection size: 20 µL
Sample: System suitability solution
Resolution: NLT 8.0 between cefazolin and cefazolin epimer, 254 nm
Samples: Blank, Standard solution, and Sample solution
Calculate the percentage of tetrazolylacetic acid and tetrazolylacetamide acetal in the portion of Cefazolin Sodium taken:
Result = (rU(210)/rS(254)) × (CS/CU) × (1/F) × 100
Calculate the percentage of each impurity other than tetrazolylacetic acid and tetrazolylacetamide acetal in the portion of Cefazolin Sodium taken:
Result = (rU(254)/rS(254)) × (CS/CU) × (1/F) × 100
Acceptance criteria: See Table 2. Disregard peaks corresponding to those in the Blank.
• Optical Rotation, Specific Rotation 781S
Sample solution: 55 mg/mL, in 0.1 M sodium bicarbonate
Acceptance criteria: 10 to 24
• pH 791: 4.06.0, in a solution containing 100 mg/mL of cefazolin
• Water Determination, Method I 921: NMT 6.0%
• Sterility Tests 71: Where the label states that Cefazolin Sodium is sterile, it meets the requirements when tested as directed for Test for Sterility of the Product to Be Examined, Membrane Filtration.
• Bacterial Endotoxins Test 85: Where the label states that Cefazolin Sodium is sterile or must be subjected to further processing during the preparation of injectable dosage forms, it contains NMT 0.15 USP Endotoxin Unit/mg of cefazolin.
• 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.
• USP Reference Standards 11
USP Endotoxin RS
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USP35NF30 Page 2533Pharmacopeial Forum: Volume No. 34(6) Page 1438