BRIEFING

 Polyethylene Glycol Monomethyl Ether 350. Because there is no existing NF monograph for this excipient, a new monograph based on validated methods of analysis is proposed. The current NF monograph for Polyethylene Glycol Monomethyl Ether covers nominal average molecular weights ranging from 350 to 10000 that include Polyethylene Glycol Monomethyl Ether 350 and Polyethylene Glycol Monomethyl Ether 550. It is proposed to develop separate NF monographs for Polyethylene Glycol Monomethyl Ether 350 and Polyethylene Glycol Monomethyl Ether 550 to reflect its use. See also the Briefing for the NF monographs for Polyethylene Glycol Monomethyl Ether and Polyethylene Glycol Monomethyl Ether 550, appearing elsewhere in this issue of PF.

1. The procedure in the test for Limit of Ethylene Glycol and Diethylene Glycol is based on a GC with a midcolumn backflush method of analysis using the DB-WAX Ultra Inert (UI) brand of column with G16 phase. The typical retention times for ethylene glycol and triethylene glycol are about 6.6 and 8.6 min, respectively.

2. The procedure in the test for Free Ethylene Oxide and 1,4-Dioxane is based on a headspace GC method of analysis using the Restek RTX-1701 brand of column with G46 phase. The typical retention times for acetaldehyde, ethylene oxide, and 1,4-dioxane are about 2.6, 2.8, and 12.3 min, respectively.

3. The procedure in the test for Limit of 2-Methoxyethanol is based on a GC with a midcolumn backflush method of analysis using the Agilent DB-WAX Ultra Inert (UI) brand of column with G16 phase. The typical retention times for 1-propanol and 2-methoxyethanol are about 2.1 and 4.0 min, respectively.

 (CE: S. Saladi)

 Case ID—SUB-442