Narasin Premix
» Narasin Premix contains Narasin Granular mixed with suitable diluents and inactive ingredients. It contains not less than 90 percent and not more than 110 percent of the labeled amount of narasin.
Packaging and storage— Preserve in well-closed containers. Avoid moisture and excessive heat.
Labeling— Label it to indicate that it is for animal use only. The label bears the statement, “Do not feed undiluted.”
Identification— The retention time of the major peak for narasin A in the chromatogram of the Assay preparation corresponds to that of the Standard preparation, as obtained in the Assay.
Loss on drying 731 Dry it in vacuum at 60 for 3 hours: it loses not more than 12% of its weight.
Diluent, Mobile phase, Neutralized methanol, Derivatizing reagent, Resolution solution, Standard preparations, and Chromatographic system —Proceed as directed in the Assay under Narasin Granular.
Assay preparation— Transfer about 5 g of Narasin Premix, accurately weighed, to a suitable container, add 200.0 mL of Diluent, and shake by mechanical means for 1 hour. Allow the solids to settle, and quantitatively dilute an accurately measured volume of the supernatant with Diluent to obtain a solution containing about 20 µg of narasin per mL. Pass a portion of this solution through a filter having a 0.5-µm or finer porosity, and use the filtrate as the Assay preparation.
Procedure— Proceed as directed for Procedure in the Assay under Narasin Granular. Calculate the biopotency, in mg per g, in the portion of Narasin Premix taken by the formula:
(0.001)(CA FA + CD +I FD +I)(VE / M)
in which M is the weight, in g, of Narasin Premix taken to prepare the Assay preparation; and the other terms are as defined therein.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Ian DeVeau, Ph.D.
Director, Veterinary Drugs and Radiopharmaceuticals
(VET05) Veterinary Drugs 05
Reference Standards Lili Wang, Technical Services Scientist
USP32–NF27 Page 3039
Pharmacopeial Forum: Volume No. 32(1) Page 126
Chromatographic Column—
Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.