title: Suitability of a liquid chromatography assay of neomycin sulfate to replace the microbiological assay for neomycin in USP Monographs.
abstract: The current USP National Formulary contains 65 Monographs for drug formulations containing neomycin. All 65 Monographs prescribe a bioassay for neomycin assay. This bioassay, based on cell culture, is labor intensive, has poor precision, and cannot be adapted for purity or identification. High-performance anion-exchange chromatography with integrated pulsed amperometric detection (HPAE-IPAD), a liquid chromatography technique, has been shown to be suitable for neomycin purity analysis and neomycin assay of an over-the-counter first aid cream (Hanko and Rohrer [17]). Here we propose that an HPAE-IPAD assay can replace the bioassay in the 65 neomycin-containing Monographs. We applied the HPAE-IPAD assay to four neomycin-containing drug products representing the four classes of formulations found in the 65 Monographs, liquid, solid, suspension, and cream. Each drug was analyzed with two chromatography systems, and on 3 separate days. For all products, HPAE-IPAD measurements were precise and accurate with respect to the label concentrations. There was also high accuracy for spike recovery of neomycin from the four drug products throughout 70-150% of the labeled concentration. These results suggest that an HPAE-IPAD assay would be an accurate assay for neomycin, and would be faster and more precise than the current bioassay.
authors.affiliation: Dionex Corporation, Sunnyvale, CA 94088-3603, USA. v.hanko@att.net
authors.forename: Valoran P
authors.initials: VP
authors.lastname: Hanko
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Rohrer
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002852:Chromatography, Ion Exchange / Q000379:methods*; D004304:Dosage Forms; D009355:Neomycin / Q000032:analysis* / Q000737:chemistry; D010602:Pharmacopoeias as Topic; D015203:Reproducibility of Results; D013997:Time Factors; D014481:United States
chemical_list: D000900:Anti-Bacterial Agents; D004304:Dosage Forms; D009355:Neomycin