Quality Evaluation of Gentamicin Sulfate Reference Standards in Japanese Pharmacopoeia Using Hydrophilic Interaction Chromatography Combined With Tandem Mass Spectrometry.

This article focuses on developing and validating a physicochemical analytical method using hydrophilic interaction liquid chromatography–tandem mass spectrometry (HILIC-MS/MS) for quality control of gentamicin sulfate (GmS), a multicomponent aminoglycoside antibiotic composed mainly of gentamicin C1, C1a, and C2. The study established theoretical potencies for each C component based on quantitative ^1H NMR purity data and microbiological assays, revealing potency ratios of 1.00, 1.21, and 1.80 for C1, C2, and C1a, respectively. Two Japanese Pharmacopoeia (JP) reference standard lots were analyzed, showing differences in component content and impurities (sisomicin and garamine), with HILIC-MS/MS potency estimates closely matching microbiological assay results. The method offers a complementary physicochemical approach for routine GmS potency and impurity testing, addressing limitations of traditional microbiological assays and supporting improved quality control.