BRIEFING

 dl-Lactide and Glycolide (75:25) Copolymer 20000 Acid. Because there is no existing NF monograph for this excipient, a new monograph based on validated methods of analysis is proposed. Please see the background information for developing the monographs for lactide and glycolide polymers and related polymeric excipients, including this monograph, in the Stimuli article A Practical Approach to Compendial Nomenclature and Testing For Lactide and Glycolide Polymers and Related Polymeric Excipients, which appeared in PF 48(2) [Mar.–Apr. 2022]. The first three lactide-glycolide polymer monographs have been released to the USP–NF with the official date of May 1, 2025: dl-Lactide and Glycolide (50:50) Copolymer 12000 Acid, dl-Lactide and Glycolide (50:50) Copolymer 12000 Ethyl Ester, and dl-Lactide and Glycolide (50:50) Copolymer 46000 Acid. The proposal of the fourth lactide-glycolide polymer monograph for dl-Lactide Homopolymer 14000 Acid was published in PF 50(4) [Jul.–Aug. 2024]. The proposal for dl-Lactide and Glycolide (50:50) Copolymer 63000 Acid, another lactide-glycolide polymer monograph, appears elsewhere in this issue of PF.

 The test for Limit of dl-Lactide and Glycolide is based on a validated gas chromatographic method of analysis performed with the Agilent DB-225 brand of column or the Restek Rtx-225 brand of column with G7 phase. The typical retention times for dl-lactide, glycolide, and γ-decalactone are approximately 5.7, 6.9, and 8.1 min, respectively.

 (CE: P. Zhang)

 Case ID—SUB-1541