Sterility 71
Where the label states that Ceforanide is sterile, it meets the requirements when tested as directed for
Membrane Filtration under
Test for Sterility of the Product to be Examined, except to dissolve 6 g of Ceforanide in
Fluid A to each 1000 mL of which has been added 10 g of sterile
L-lysine, and to rinse the membrane with three 100-mL portions of
Fluid D and one 100-mL portion of
Fluid A.
Assay
Mobile phase
Mix 18 mL of tetrabutylammonium hydroxide solution (1 in 10) and 8.6 mL of 11 N potassium hydroxide, and add the mixture to 700 mL of water. Add 200 mL of methanol, adjust with phosphoric acid to a pH of 7.0, and add water to obtain 1000 mL of solution, making adjustments if necessary (see
System Suitability under
Chromatography 621). Filter, using a filter having a porosity of 1 µm or finer, and degas.
Standard preparation
Dissolve an accurately weighed quantity of
USP Ceforanide RS in
Mobile phase to obtain a solution having a known concentration of about 1 mg per mL. Use this solution within 5 minutes.
Assay preparation
Using a suitable quantity of Ceforanide, accurately weighed, proceed as directed under Standard preparation. Use this solution within 5 minutes.
Chromatographic system
(see
Chromatography 621)The liquid chromatograph is equipped with a 254-nm detector and a 4-mm × 30-cm column that contains 5- to 10-µm packing L1. The flow rate is about 1 mL per minute. Chromatograph the
Standard preparation, and record the peak responses as directed under
Procedure: the column efficiency determined from the analyte peak is not less than 1900 theoretical plates; the tailing factor for the analyte peak is not more than 1.2; the capacity factor,
k¢, is not less than 1.8 and not more than 5.0; and the relative standard deviation for replicate injections is not more than 1.5%.
Procedure
Separately inject equal volumes (about 10 µL) of the
Standard preparation and the
Assay preparation into the chromatograph, record the chromatograms, and measure the responses for the major peaks. Calculate the quantity, in µg, of C
20H
21N
7O
6S
2 in each mg of the Ceforanide taken by the formula:
(CP / M)(rU / rS),
in which
C is the concentration, in mg per mL, of
USP Ceforanide RS in the
Standard preparation;
P is the potency, in µg per mg, of the
USP Ceforanide RS;
M is the concentration, in mg per mL, of the
Assay preparation, based on the amount of Ceforanide taken and the extent of dilution; and
rU and
rS are the peak responses obtained from the
Assay preparation and the
Standard preparation, respectively.