BRIEFING

 Citrulline. This proposal is based on the version of the monograph official as of May 1, 2022. On the basis of comments received, the following changes are being proposed:

1. Replace the 25-cm column with a 15-cm column in the Assay and in the test for Related Compounds to shorten the run time and improve the chromatography.

2. Remove USP N-Acetyl-l-leucine RS from the System suitability solution in the Assay and in the test for Related Compounds.

3. Add new System suitability requirements in the test for Related Compounds.

4. The liquid chromatographic procedure in the Assay and the test for Related Compounds is based on analyses performed with the SIELC Primesep 100 brand of L85 column. Typical retention times for citrulline and N-acetylornithine are approximately 5.5 and 6.7 min, respectively.

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

 (NBDS: B. Koshy)

 Case ID—SUB-90