Nafcillin Sodium
454.484-Thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid, 6-[[(2-ethoxy-1-naphthalenyl)carbonyl]amino]-3,3-dimethyl-7-oxo-, monosodium salt, monohydrate, [2S-(2
,5,6
)].
Monosodium (2S,5R,6R)-6-(2-ethoxy-1-naphthamido)-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylate monohydrate
[7177-50-6].Anhydrous 436.47
[985-16-0].» Nafcillin Sodium has a potency equivalent to not less than 820 µg of nafcillin (C21H22N2O5S) per mg.
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.
Identification—
Solution:
50 µg per mL.
Medium:
water.
B:
The retention time of the major peak for nafcillin in the chromatogram of the Assay preparation corresponds to that in the chromatogram of the Standard preparation, as obtained in the Assay.
C:
It responds to the tests for Sodium 
191
.
191.
Crystallinity 695:
meets the requirements.
695:
meets the requirements.
pH 791:
between 5.0 and 7.0, in a solution containing 30 mg per mL.
791:
between 5.0 and 7.0, in a solution containing 30 mg per mL.
Water, Method I 921:
between 3.5% and 5.3%.
921:
between 3.5% and 5.3%.
Other requirements—
Where the label states that Nafcillin Sodium is sterile, it meets the requirements for Sterility Tests 71 and for Bacterial endotoxins under Nafcillin for Injection. Where the label states that Nafcillin Sodium must be subjected to further processing during the preparation of injectable dosage forms, it meets the requirements for Bacterial endotoxins under Nafcillin for Injection.
71 and for Bacterial endotoxins under Nafcillin for Injection. Where the label states that Nafcillin Sodium must be subjected to further processing during the preparation of injectable dosage forms, it meets the requirements for Bacterial endotoxins under Nafcillin for Injection.
Assay—
Acetic acid solution—
Prepare a 1 in 20 solution of glacial acetic acid and water.
0.05 M Sodium acetate—
Dissolve 6.8 g of sodium acetate in about 800 mL of water, adjust with Acetic acid solution to a pH of 7.5, dilute with water to 1000 mL, and mix.
Mobile phase—
Prepare a suitable filtered and degassed mixture of 0.05 M Sodium acetate and acetonitrile (70:30). Make adjustments if necessary (see System Suitability under Chromatography 621).
621).
Diluent—
Dissolve 6.9 g of sodium citrate in about 800 mL of water, adjust with 1 N hydrochloric acid to a pH of 7.0, dilute with water to 1000 mL, and mix.
Standard preparation—
Dissolve an accurately weighed quantity of USP Nafcillin Sodium RS quantitatively in Diluent to obtain a solution having a known concentration of about 400 µg of nafcillin (C21H22N2O5S) per mL.
Resolution solution—
Prepare a solution of orcinol in water containing about 35 mg per mL. Add 0.5 mL of this solution to 25 mL of Standard preparation to obtain a solution containing about 0.7 mg of orcinol and 400 µg of nafcillin per mL.
Assay preparation—
Transfer about 88 mg of Nafcillin Sodium, accurately weighed, to a 200-mL volumetric flask, dilute with Diluent to volume, and mix.
Chromatographic system
(see Chromatography 621)—The liquid chromatograph is equipped with a 254-nm detector and a 3.9-mm × 30-cm column containing packing L1. The flow rate is about 1 mL per minute. Chromatograph the Resolution solution, and record the peak responses as directed for Procedure: the relative retention times are about 0.8 for orcinol and 1.0 for nafcillin; and the resolution between the orcinol and nafcillin peaks is not less than 2.0. Chromatograph the Standard preparation, and record the responses as directed for Procedure: the tailing factor for the analyte peak is not more than 1.5; and the relative standard deviation for replicate injections is not more than 2.0%.
621)—The liquid chromatograph is equipped with a 254-nm detector and a 3.9-mm × 30-cm column containing packing L1. The flow rate is about 1 mL per minute. Chromatograph the Resolution solution, and record the peak responses as directed for Procedure: the relative retention times are about 0.8 for orcinol and 1.0 for nafcillin; and the resolution between the orcinol and nafcillin peaks is not less than 2.0. Chromatograph the Standard preparation, and record the responses as directed for Procedure: the tailing factor for the analyte peak is not more than 1.5; and the relative standard deviation for replicate injections is not more than 2.0%.
Procedure—
Separately inject equal volumes (about 20 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 nafcillin (C21H22N2O5S) in each mg of Nafcillin Sodium taken by the formula:
200(C / W)(rU / rS)
in which C is the concentration, in µg per mL, of nafcillin (C21H22N2O5S) in the Standard preparation; W is the weight, in mg, of the portion of Nafcillin Sodium taken; and rU and rS are the nafcillin peak responses obtained from the Assay preparation and the Standard preparation, respectively.
Auxiliary Information—
Please check for your question in the FAQs before contacting USP.
Chromatographic Column—
| Topic/Question | Contact | Expert Committee |
| Monograph | Ahalya Wise, M.S.
Scientist 1-301-816-8161 |
(MDANT05) Monograph Development-Antibiotics |
| Reference Standards | Lili Wang, Technical Services Scientist 1-301-816-8129 RSTech@usp.org |
USP32–NF27 Page 3021
Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.