Cephradine for Injection
»Cephradine for Injection contains not less than 90.0percent and not more than 115.0percent of the labeled amount of cephradine,calculated as the sum of cephradine (C16H19N3O4S)and cephalexin (C16H17N3O4S).
Constituted solution—
At the time of use,it meets the requirements for Constituted Solutionsunder Injections á1ñ.
Identification—
Dilute the contents of 1container of Cephradine for Injection with water to obtain a test solution containing about 3mg of cephradine per mL.Proceed as directed in the Identificationtest under Cephradine Capsules,beginning with “Place a suitable thin-layer chromatographic plate”:the RFvalue of the principal spot obtained from the test solution corresponds to that obtained from the Standard solution.
Bacterial endotoxins á85ñ—
It contains not more than 0.20USP Endotoxin Unit per mg of cephradine.
Sterility á71ñ—
It meets the requirements when tested as directed for Membrane Filtrationunder Test for Sterility of the Product to be Examined.
pHá791ñ:
between 8.0and 9.6,in a solution containing 10mg per mL.
Loss on drying á731ñ—
Dry about 100mg,accurately weighed,in a capillary-stoppered bottle in vacuum at a pressure not exceeding 5mm of mercury at 60
for 3hours:it loses not more than 5.0%of its weight.
for 3hours:it loses not more than 5.0%of its weight.
Particulate matter á788ñ:
meets the requirements for small-volume injections.
Other requirements—
It meets the requirements for Uniformity of Dosage Units á905ñand Labelingunder Injections á1ñ.
Assay—
Mobile phase,Standard preparation,Resolution solution,and Chromatographic system—
Proceed as directed in the Assayunder Cephradine.
Assay preparation 1
(where it is represented as being in a single-dose container)—Constitute Cephradine for Injection in a volume of water,accurately measured,corresponding to the volume of solvent specified in the labeling.Withdraw all of the withdrawable contents,using a suitable hypodermic needle and syringe,and dilute quantitatively with Mobile phaseto obtain a solution containing about 0.5mg of cephradine per mL.
Assay preparation 2
(where the label states the quantity of cephradine in a given volume of constituted solution)—Constitute Cephradine for Injection in a volume of water,accurately measured,corresponding to the volume of solvent specified in the labeling.Dilute an accurately measured volume of the constituted solution quantitatively with Mobile phaseto obtain a solution containing about 0.5mg of cephradine per mL.
Procedure—
Separately inject equal volumes (about 10µL)of the Standard preparationand Assay preparation 1or Assay preparation 2into the chromatograph,record the chromatograms,and measure the responses for the major peaks.Calculate the quantity,in mg,of cephradine (sum of cephradine and cephalexin)withdrawn from the container,or in the portion of constituted solution taken by the formula:
(CP)(L/1000D)(rU/rS),
in which Cis the concentration,in mg per mL,of USP Cephradine RSin the Standard preparation,Pis the designated potency,in µg per mg,of USP Cephradine RS,Lis the labeled quantity,in mg of cephradine,in the container taken to prepare Assay preparation 1,or in the volume of constituted solution taken to prepare Assay preparation 2,Dis the concentration,in mg of cephradine per mL,of Assay preparation 1or Assay preparation 2,based on the labeled quantity in the container or in the portion of constituted solution taken,respectively,and the extent of dilution,and rUand rSare the sums of the cephradine and cephalexin peak responses obtained from Assay preparation 1or Assay preparation 2and the Standard preparation,respectively.
Auxiliary Information—
Staff Liaison:William W.Wright,Ph.D.,Scientific Fellow
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 422
Phone Number:1-301-816-8335