title: Novel application of square-wave adsorptive-stripping voltammetry for the determination of xanthohumol in spent hops.
abstract: This paper reports the development of a novel electrochemical assay for xanthohumol (XN) by square-wave adsorptive-stripping voltammetry (SWAdSV) with a hanging mercury drop electrode. The method showed good repeatability (CV < 2%) and linearity (between 10 and 250 μg L(-1)), as well as suitable limits of detection (2.6 μg L(-1)) and quantification (8.8 μg L(-1)). The method was applied for the quantification of this compound in spent hops, and the results obtained were compared with the HPLC-UV method. XN contents determined by the SWAdSV method were 16 ± 1 and 100 ± 4 μg L(-1) for aqueous and methanolic extracts, respectively. The developed new methodology considerably reduces the analysis time, approximately from 25 min (HPLC-UV method) to 7 min, enabling a high sample throughput. In addition, the detection and quantification limits were approximately 5-fold lower than those obtained with the chromatographic method.
authors.affiliation: Departamento de Química e Bioquímica, Universidade do Porto, Porto, Portugal.
authors.forename: Manuela M
authors.initials: MM
authors.lastname: Moreira
authors.forename: Ana M
authors.initials: AM
authors.lastname: Carvalho
authors.forename: Ines M
authors.initials: IM
authors.lastname: Valente
authors.forename: Luis M
authors.initials: LM
authors.lastname: Goncalves
authors.forename: Jose A
authors.initials: JA
authors.lastname: Rodrigues
authors.forename: Aquiles A
authors.initials: AA
authors.lastname: Barros
authors.forename: Luis F
authors.initials: LF
authors.lastname: Guido
mesh_terms: D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D005419:Flavonoids / Q000032:analysis*; D027582:Humulus / Q000737:chemistry*; D010936:Plant Extracts / Q000032:analysis*; D011427:Propiophenones / Q000032:analysis*
chemical_list: D005419:Flavonoids; D010936:Plant Extracts; D011427:Propiophenones; C104536:xanthohumol