Determination of Residual Ethylene Oxide in Spectinomycin Hydrochloride Bulk Drug by Dynamic Headspace Gas Chromatography
Abstract A dynamic headspace gas chromatographic method was developed for the determination of residual ethylene oxide (EtO) in a pharmaceutical bulk drug, spectinomycin hydrochloride. The recommended column is PoraPLOT Q; PoraPLOT U was demonstrated to be equivalent. A detection limit of 2 ppb was achieved, and linearity was established to the highest value tested (5 ppm). The detection limit was 2-3 orders of magnitude lower than that achieved in previously published methods for EtO in pharmaceutical bulk drugs. Precision studies yielded relative standard deviations ranging from 2 to 10% over the 10-575 ppb concentration range. The method was applied to support EtO sterilization studies conducted at The Upjohn Company and was implemented for routine use. The sterilization studies demonstrated that residual levels of EtO <10 ppb are achievable.