titoli, abstracts, parole chiave >>>
Development and characterization of an ascorbate oxidase-based sensor–biosensor system for telemetric detection of AA and antioxidant capacity in fresh orange juice

Barberis, Antonio and Spissu, Ylenia and Bazzu, Gianfranco and Fadda, Angela and Azara, Emanuela and Sanna, Daniele and Schirra, Mario and Serra, Pier Andrea (2014) Development and characterization of an ascorbate oxidase-based sensor–biosensor system for telemetric detection of AA and antioxidant capacity in fresh orange juice. Analytical chemistry, Vol. 86 (17), p. 8727-8734. ISSN 0003-2700. eISSN 1520-6882. Article.

Full text not available from this repository.

DOI: 10.1021/ac502066a

Alternative URLs:

Abstract

A new carbon ascorbate oxidase-based sensor–biosensor system (SB) was coupled to a dual-channel telemetric device for online simultaneous electrochemical detection of ascorbic acid (AA) and antioxidant capacity in Hamlin, Sanguinello, and Moro orange varieties. The electrocatalytic performances of the SB were investigated by cyclic voltammetry and amperometric techniques. The phenol composition of orange juice of each variety, and the cyclic voltammetries of the most represented phenols, were provided. The in vitro calibrations were performed in PBS (pH 5.6), applying a constant potential of +500 mV. A standard mixture of phenols, based on orange juice composition, was used as reference material for studying SB behavior. SB works at an applied potential of +500 mV, in a concentration range comprised between the LOD 0.26 μM and 20 μM. In this concentration range, limiting the data acquisition time to 2 min, the problems of electrode passivation due to phenols polymerization were overcome. AA calibration showed that the biosensor registered statistically lower currents than the sensor since the enzyme oxidized AA before it reached the electrode surface. Standard mixture calibration showed that currents registered by sensor and biosensor did not statistically differ. The difference between sensor and biosensor AA registered currents was used to calculate an AA selectivity index and, consequently, to determine the AA content and the antioxidant capacity in the juices. The novelty of the SB is its ability to distinguish between AA and phenols contribution to antioxidant capacity. The obtained results were in accordance with reference methods.

Item Type:Article
ID Code:10093
Status:Published
Refereed:Yes
Uncontrolled Keywords:Sensor–biosensor system (SB), dual-channel telemetric device, ascorbic acid (AA) selectivity index
Subjects:Area 05 - Scienze biologiche > BIO/14 Farmacologia
Area 03 - Scienze chimiche > CHIM/03 Chimica generale e inorganica
Area 03 - Scienze chimiche > CHIM/10 Chimica degli alimenti
Divisions:002 Altri enti e centri di ricerca del Nord Sardegna > CNR-Consiglio Nazionale delle Ricerche > Istituto di scienze delle produzioni alimentari, Sassari
002 Altri enti e centri di ricerca del Nord Sardegna > CNR-Consiglio Nazionale delle Ricerche > Istituto di chimica biomolecolare, Sassari
001 Università di Sassari > 01-a Nuovi Dipartimenti dal 2012 > Medicina Clinica e Sperimentale
Publisher:American Chemical Society
ISSN:0003-2700
eISSN:1520-6882
Deposited On:12 Sep 2014 11:48

I documenti depositati in UnissResearch sono protetti dalle leggi che regolano il diritto d'autore

Repository Staff Only: item control page