Rapid pretreatment-free evaluation of antioxidant capacity in extra virgin olive oil using a laser-nanodecorated electrochemical lab-on-strip

Filippo Silveri; Annalisa Scroccarello; Flavio Della Pelle; Michele Del Carlo; Dario Compagnone

doi:10.1016/j.foodchem.2023.136112

Rapid pretreatment-free evaluation of antioxidant capacity in extra virgin olive oil using a laser-nanodecorated electrochemical lab-on-strip

Food Chem. 2023 Sep 15:420:136112. doi: 10.1016/j.foodchem.2023.136112. Epub 2023 Apr 8.

Authors

Filippo Silveri¹, Annalisa Scroccarello¹, Flavio Della Pelle², Michele Del Carlo¹, Dario Compagnone³

Affiliations

¹ Department of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Campus "Aurelio Saliceti" Via R. Balzarini 1, 64100 Teramo, Italy.
² Department of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Campus "Aurelio Saliceti" Via R. Balzarini 1, 64100 Teramo, Italy. Electronic address: fdellapelle@unite.it.
³ Department of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Campus "Aurelio Saliceti" Via R. Balzarini 1, 64100 Teramo, Italy. Electronic address: dcompagnone@unite.it.

PMID: 37059022
DOI: 10.1016/j.foodchem.2023.136112

Abstract

An electroanalytical lab-on-a-strip device for the direct extra-virgin olive oil (EVOO) antioxidant capacity evaluation is proposed. The lab-made device is composed of a CO₂ laser nanodecorated sensor combined with a cutter-plotter molded paper-strip designed for EVOOs sampling and extraction. Satisfactory performance towards the most representative o-diphenols of EVOOs i.e., hydroxytyrosol (HY) and oleuropein (OL) were achieved; good sensitivity (LOD_HY = 2 µM; LOD_OL = 0.6 µM), extended linear ranges (HY: 10-250 µM; OL: 2.5-50 µM) and outstanding reproducibility (RSD < 5%, n = 3) were obtained in rectified oil. The device was challenged for the extraction-free analysis of 15 different EVOO samples, with satisfactory recoveries (90-94%; RSD < 5%, n = 3) and correlation with classical photometric assays (r ≥ 0.91). The proposed device includes all analysis steps, needs 4 µL of sample, and returns reliable results in 2 min, resulting portable and usable with a smartphone.

Keywords: Direct sample analysis; Extraction-free; Lab on a paper device; Nanodecorated ink; Phenolic compounds; Stencil printing.

MeSH terms

Antioxidants* / analysis
Lasers*
Olive Oil / analysis
Reproducibility of Results

Substances

Olive Oil
Antioxidants
3,4-dihydroxyphenylethanol