title: Development of an analytical method for the determination of polyphenolic compounds in vegetable origin samples by liquid chromatography and pulsed amperometric detection at a glassy carbon electrode.
abstract: A sensitive and accurate method for the determination of polyphenolic compounds in artichoke bract extracts and olive mill wastewaters by liquid chromatography coupled with pulsed amperometric detection at a glassy carbon working electrode was developed. Preliminary experiments were carried out by cyclic voltammetry to investigate the electrochemical behavior of polyphenols under different mobile phase compositions, and to test the detection and cleaning electrode potentials. Chromatographic separations were performed by using a core-shell C18 column, eluted with acetic acid and acetonitrile, by combined concave-linear binary gradients. Under the optimized experimental conditions, a good column efficiency and peak symmetry were observed, also for stereo and positional isomeric compounds. The developed three-step potential waveform for pulsed amperometric detection was successfully applied for the sensitive chromatographic determination of polyphenols in artichoke extracts and olive mill wastewaters. Linearity, precision and sensitivity of the proposed method have been evaluated. A wide linear range of response (up to 20 mg/L) has been obtained for all the investigated compounds. Detection and quantification limits in the vegetable origin sample extracts were in the range 0.004-0.6 mg/L and 0.01-2mg/L, respectively, while the injection-to-injection repeatability (n=6) ranged from 5 to 13%. The obtained results confirmed the excellent sensitivity of the electrochemical detection, and its suitability for the determination of electroactive polyphenolic compounds at low concentration levels.
authors.affiliation: Dipartimento di Scienze Agrarie, degli Alimenti e dell'Ambiente and CSRA - Centro Servizi di Ricerca Applicata, Università degli Studi di Foggia, Via Napoli, 25, 71100 Foggia, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Natale
authors.affiliation: Dipartimento di Scienze Agrarie, degli Alimenti e dell'Ambiente and CSRA - Centro Servizi di Ricerca Applicata, Università degli Studi di Foggia, Via Napoli, 25, 71100 Foggia, Italy. Electronic address: donatella.nardiello@unifg.it.
authors.forename: Donatella
authors.initials: D
authors.lastname: Nardiello
authors.affiliation: Dipartimento di Scienze Agrarie, degli Alimenti e dell'Ambiente and CSRA - Centro Servizi di Ricerca Applicata, Università degli Studi di Foggia, Via Napoli, 25, 71100 Foggia, Italy.
authors.forename: Carmen
authors.initials: C
authors.lastname: Palermo
authors.affiliation: Istituto Zooprofilattico Sperimentale della Puglia e della Basilicata, Via Manfredonia, 20, 71100 Foggia, Italy.
authors.forename: Marilena
authors.initials: M
authors.lastname: Muscarella
authors.affiliation: Dipartimento di Scienze Agrarie, degli Alimenti e dell'Ambiente and CSRA - Centro Servizi di Ricerca Applicata, Università degli Studi di Foggia, Via Napoli, 25, 71100 Foggia, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Quinto
authors.affiliation: Dipartimento di Scienze Agrarie, degli Alimenti e dell'Ambiente and CSRA - Centro Servizi di Ricerca Applicata, Università degli Studi di Foggia, Via Napoli, 25, 71100 Foggia, Italy.
authors.forename: Diego
authors.initials: D
authors.lastname: Centonze
mesh_terms: D002244:Carbon / Q000737:chemistry*; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation / Q000379:methods; D002853:Chromatography, Liquid / Q000379:methods*; D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D005898:Glass / Q000737:chemistry*; D057230:Limit of Detection; D010710:Phosphates; D059808:Polyphenols / Q000032:analysis*; D014675:Vegetables / Q000737:chemistry*
chemical_list: D010710:Phosphates; D059808:Polyphenols; D002244:Carbon; C009285:sodium polymetaphosphate
keywords: Combined concave-linear binary gradient; Glassy carbon electrode; High performance liquid chromatography; Polyphenolic compounds; Pulsed amperometric detection