Cephalothin for Injection
»Cephalothin for Injection contains an amount of Cephalothin Sodium equivalent to not less than 90.0percent and not more than 115.0percent of the labeled amount of cephalothin (C16H16N2O6S2).It may contain Sodium Bicarbonate.
Packaging and storage— Preserve in Containers for Sterile Solidsas described under Injections á1ñ.
Constituted solution— At the time of use,it meets the requirements for Constituted Solutionsunder Injections á1ñ.
Specific rotation á781Sñ: between +124and +134,calculated on the dried and sodium bicarbonate-free basis.
Test solution: a known amount of specimen,equivalent to about 50mg of cephalothin,per mL,in water.
Bacterial endotoxins á85ñ— It contains not more than 0.13USP Endotoxin Unit per mg of cephalothin.
Sterility á71ñ— It meets the requirements when tested as directed for Membrane Filtrationunder Test for Sterility of the Product to be Examined.
Uniformity of dosage units á905ñ: meets the requirements.
Procedure for content uniformity— Perform the Assayon individual containers using Assay preparation 1or Assay preparation 2,or both,as appropriate.
pHá791ñ: between 6.0and 8.5,in the solution constituted as directed in the labeling.
Particulate matter á788ñ: meets the requirements for small-volume injections.
Content of sodium bicarbonate (if present)— Dissolve about 1g of it,accurately weighed,in 50mLof water.Add methyl orange TS,and titrate with 0.1Nsulfuric acid VS.Each mLof 0.1Nsulfuric acid is equivalent to 8.401mg of NaHCO3.Calculate the percentage of sodium bicarbonate,and use the value obtained to calculate the Specific rotationon the dried and sodium bicarbonate-free basis.
Other requirements— It meets the requirements for Identificationtest Aand Loss on dryingunder Cephalothin Sodium.It meets also the requirements for Labelingunder Injections á1ñ.
Assay—
Mobile phase ,Resolution solution,and Chromatographic system—Proceed as directed in the Assayunder Cephalothin Sodium.
Standard preparation— Dissolve a suitable quantity of USP Cephalothin Sodium RS,accurately weighed,in Mobile phaseto obtain a solution having a known concentration of about 1mg of cephalothin per mL.
Assay preparation 1 (where it is represented as being in a single-dose container)—Constitute Cephalothin 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 having a concentration of about 1mg of cephalothin per mL.
Assay preparation 2 (where the label states the quantity of cephalothin in a given volume of constituted solution)—Constitute 1container of Cephalothin for Injection in a volume of water,accurately measured,corresponding to the volume of solvent specified in the labeling.Dilute an accurately measured portion of the constituted solution quantitatively with Mobile phaseto obtain a solution having a concentration of about 1mg of cephalothin per mL.
Procedure— Proceed as directed in the Assayunder Cephalothin Sodium.Calculate the quantity,in mg,of cephalothin (C16H16N2O6S2)in the container,and in the portion of constituted solution taken by the formula:
(L/D)(CP/1000)(rU/rS),
in which Lis the labeled quantity of cephalothin in the container,or in the volume of constituted solution taken;Dis the concentration,in mg per mL,of cephalothin in Assay preparation 1or in Assay preparation 2,on the basis of the labeled quantity in the container,or in the portion of constituted solution taken,respectively,and the extent of dilution;and the other terms are as defined therein.Where the test for Uniformity of dosage unitshas been performed using the Procedure for content uniformity,use the average of these determinations as the Assayvalue.
Auxiliary Information— Staff Liaison:William W.Wright,Ph.D.,Scientific Fellow
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 417
Phone Number:1-301-816-8335