Lab-on-valve combined with a kinetic-matching approach for fast evaluation of total antioxidant capacity in wines

• Type: Article in International Scientific Journal
• Date: 2014

Authors

Ines I Ramos (Author) Other; Miguel A Maia (Author) Other; Salette Reis (Author) FFUP; Luis M Magalhaes (Author) Other; Marcela A Segundo (Author) FFUP

Journal

Title: Analytical Methods

Vol. 6

Pages: 3622-3628

ISSN: 1759-9660

Publisher: Royal Society of Chemistry

Indexing

ISI Web of Knowledge - 8 Citations

Scopus - 9 Citations

Scientific classification

FOS: Agrarian Sciences > Other Agrarian Sciences

Other information

Authenticus ID: P-009-GP9

DOI: 10.1039/c3ay42185f

Abstract (EN): The ABTS(center dot+) assay, based on reduction of the 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonate) radical cation, has been automated using flow injection based methods, but biased results are often obtained because the scavenging reaction is not complete upon detection, providing underestimated antioxidant values for samples containing slow reacting compounds. In this work a mesofluidic lab-on-valve (LOV) system was developed to provide fast determination of total antioxidant capacity in a miniaturized fashion. The sample volume was downscaled to 1 mu l, with consumption of 97 mu l of ABTS (6.8 nmol) per assay. Total antioxidant capacity values for red wines were attained in <1 min by application of the kinetic matching approach, using tannic acid as standard. Calibration curves were linear between 2.5 and 12.5 mu M of tannic acid, with a determination throughput of 36 h(-1). No statistical difference was found for Trolox equivalent antioxidant capacity (TEAC) values obtained using either an end-point batch-wise microplate method (reaction time of 300 min) or the proposed LOV method.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 7