title: Derivatization of ephedrine with o-phthaldialdehyde for liquid chromatography after treatment with sodium hypochlorite.
abstract: The usefulness of the reaction with NaClO followed by derivatization with o-phthaldialdehyde (OPA) and N-acetyl-L-cysteine (NAC) has been investigated for the chromatographic analysis of ephedrine. The influence of parameters affecting the two-stage reaction has been evaluated, including concentration of NaClO, time of reaction, temperature and pH. On the basis of these studies, conditions for the pre-column and (automated) post-column determination of ephedrine are presented. The described conditions have been applied to the measurement of ephedrine in the concentration intervals 0.2-20.0 microg/ml and 2.0-50.0 microg/ml for the pre-column and post-column methods, respectively. The possibility of applying the NaClO/ OPA-NAC method to other primary, secondary and tertiary derivative amphetamines has also been evaluated.
authors.affiliation: Department of Analytical Chemistry, University of Valencia, Burjassot, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Herráez-Herández
authors.forename: P
authors.initials: P
authors.lastname: Campíns-Falcó
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D004809:Ephedrine / Q000737:chemistry*; D012973:Sodium Hypochlorite / Q000737:chemistry*; D009764:o-Phthalaldehyde / Q000737:chemistry*
chemical_list: D009764:o-Phthalaldehyde; D012973:Sodium Hypochlorite; D004809:Ephedrine