The United States Pharmacopeia (USP) General Chapters <467> Residual Solvents provide test methods for residual solvents in pharmaceuticals, and headspace gas chromatography (GC) is mainly used. Residual solvents in pharmaceuticals are classified from Class 1 to 3 based on their potential human health risk and are strictly controlled. The list of residual solvents is continuously reviewed and methylisobutylketone (MIBK) has been newly added to the Japanese Pharmacopoeia 17th Edition Supplement II (JP17 Supplement II) in 2019.
In this article, MIBK was analyzed and its chromatogram was overlaid with that of Class 2A as a reference.
Methylisobutylketone (MIBK), the newly added to JP17 Supplement II, was analyzed in water-soluble and water-insoluble samples with sufficient sensitivity by both Procedure A and B. Although MIBK was separated from the rest of Class 2A components in the chromatogram by Procedure A, it co-eluted with acetonitrile by Procedure B.