title: Mass spectrometric characterization of gentamicin components separated by the new European Pharmacopoeia method.
abstract: Liquid chromatography combined with pulsed electrochemical detection (LC-PED) is the method of choice in the European Pharmacopoeia for the determination of gentamicin and its related substances. A recently approved improved LC-PED method, with a reversed-phase C(18) column and a mobile phase consisting of trifluoroacetic acid (TFA), pentafluoropropionic acid (PFPA), sodium hydroxide and acetonitrile, showed better separation and more sensitive detection of the gentamicin components than the previous method using a polymer column. More unknown peaks can be separated from the main components and from each other. As the LC-PED method cannot be directly coupled to a mass spectrometer (MS), the unknown substances were collected after the LC column, desalted and analyzed by MS. The structures of the unknown compounds were deduced based on comparison of their fragmentation patterns with those of reference substances investigated by MS(n) experiments using an electrospray ion trap mass spectrometer. A comparison was also made with an already previously published LC-MS method using a volatile mobile phase.
authors.affiliation: Laboratorium voor Farmaceutische Analyse, Katholieke Universiteit Leuven, Herestraat 49, B-3000 Leuven, Belgium.
authors.forename: B
authors.initials: B
authors.lastname: Li
authors.forename: A
authors.initials: A
authors.lastname: Van Schepdael
authors.forename: J
authors.initials: J
authors.lastname: Hoogmartens
authors.forename: E
authors.initials: E
authors.lastname: Adams
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid; D004340:Drug Contamination; D055664:Electrochemical Techniques; D005060:Europe; D005466:Fluorocarbons / Q000737:chemistry; D005839:Gentamicins / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D057230:Limit of Detection; D015394:Molecular Structure; D010602:Pharmacopoeias as Topic; D012997:Solvents / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry; D013678:Technology, Pharmaceutical; D014269:Trifluoroacetic Acid / Q000737:chemistry
chemical_list: D000900:Anti-Bacterial Agents; D005466:Fluorocarbons; D005839:Gentamicins; D012997:Solvents; C033093:perfluoropropionic acid; D014269:Trifluoroacetic Acid