title: Drug impurity profiling strategies.
abstract: A general scheme is set up for the estimation of the impurity profile of bulk drug substances by the complex use of chromatographic, spectroscopic and hyphenated techniques. Several examples are presented as illustrations to the scheme from the authors' laboratory involving the use of chromatographic methods such as thin-layer-(TLC), gas-(GC), analytical and preparative high-performance liquid chromatography (HPLC), spectroscopic methods such as mass spectrometry (MS) and NMR spectroscopy as well as hyphenated techniques (HPLC/diode-array UV, GC/MS and HPLC/MS). In addition to summarizing earlier work, new examples are also presented: identification of an impurity (propyl 4-[diethylcarbamoyl(methoxy)]-3-methoxy phenylglyoxylate, II) in propanidid (I) and two unsaturated impurities in allylstrenol (VII) by GC/MS and HPLC/diode-array UV as well as estimation of the impurity profile of mazipredone (III) by HPLC/MS and HPLC/diode-array UV.
authors.affiliation: Chemical Works of Gedeon Richter Ltd., P.O.B. 27, H-1475 Budapest, Hungary.
authors.forename: S
authors.initials: S
authors.lastname: Görög
authors.forename: M
authors.initials: M
authors.lastname: Babják
authors.forename: G
authors.initials: G
authors.lastname: Balogh
authors.forename: J
authors.initials: J
authors.lastname: Brlik
authors.forename: A
authors.initials: A
authors.lastname: Csehi
authors.forename: F
authors.initials: F
authors.lastname: Dravecz
authors.forename: M
authors.initials: M
authors.lastname: Gasdag
authors.forename: P
authors.initials: P
authors.lastname: Horváth
authors.forename: A
authors.initials: A
authors.lastname: Laukó
authors.forename: K
authors.initials: K
authors.lastname: Varga