BRIEFING

 Sorbitan Monostearate. This proposal is based on the version of the monograph official as of January 1, 2018. On the basis of comments and data received as part of the USP monograph modernization effort, based on validated methods of analysis, it is proposed to make the following revisions:

1. Replace the current Identification A procedure with the Specific Test for Hydroxyl Value.

2. In the Assay, update the current tests for Fatty Acids and Polyols with a gel permeation chromatography (GPC) based procedure. The GPC method is performed by using the Styragel HR 0.5 and HR 1 columns in series with L21 packing. The typical relative retention times for the sorbitan tri-/higher esters, sorbitan diesters, and sorbitan monoesters peaks with respect to the isosorbide peak are 0.73, 0.76, and 0.81, respectively.

3. In the Impurities section, add the Limit of Organic Impurities test. The test utilizes similar chromatographic conditions as that of the Assay. The typical relative retention times for the isosorbide monoesters, fatty acid plus isosorbide monoesters, fatty acid (as stearic acid), and 1,4-sorbitan with respect to the isosorbide peak are 0.83, 0.84, 0.87, and 0.92, respectively.

4. Add USP Stearic Acid RS and USP Sorbitol RS to the USP Reference Standards section.

5. Revise the Definition in accordance with the newly added Assay.

6. Add Sample analysis details in Identification B.

 Additionally, minor editorial changes have been made to update the monograph to current USP style.

 (CE: D. Chavan)

 Correspondence Number—C228116