A fast, low-cost, sensitive, selective, and non-laborious method based on functionalized magnetic nanoparticles, magnetic solid-phase extraction, and fluorescent carbon dots for the fluorimetric determination of copper in wines without prior sample treatment

Matheus H Costa; Danilo T S Ferreira; Jonathan E S Pádua; Julys P A Fernandes; Josué Carinhanha C Santos; Francisco Antônio S Cunha; Mario Cesar Ugulino Araujo

doi:10.1016/j.foodchem.2021.130248

A fast, low-cost, sensitive, selective, and non-laborious method based on functionalized magnetic nanoparticles, magnetic solid-phase extraction, and fluorescent carbon dots for the fluorimetric determination of copper in wines without prior sample treatment

Food Chem. 2021 Nov 30:363:130248. doi: 10.1016/j.foodchem.2021.130248. Epub 2021 Jun 6.

Authors

Matheus H Costa¹, Danilo T S Ferreira¹, Jonathan E S Pádua¹, Julys P A Fernandes¹, Josué Carinhanha C Santos², Francisco Antônio S Cunha², Mario Cesar Ugulino Araujo³

Affiliations

¹ Universidade Federal da Paraíba, Departamento de Química, P.O. Box 5093, Zip Code 58051-970, João Pessoa, Paraíba, Brazil.
² Universidade Federal de Alagoas, Instituto de Química e Biotecnologia, Campus A.C. Simões, Tabuleiro dos Martins, Zip Code 57072-900, Maceió, Alagoas, Brazil.
³ Universidade Federal da Paraíba, Departamento de Química, P.O. Box 5093, Zip Code 58051-970, João Pessoa, Paraíba, Brazil. Electronic address: laqa@quimica.ufpb.br.

PMID: 34144418
DOI: 10.1016/j.foodchem.2021.130248

Abstract

A new fluorimetric method for copper(II) determination in wines was developed combining functionalized magnetic nanoparticles (FMNP) and fluorescent carbon dots (FCD). To produce FMNP, Fe₃O₄ was coated with Al₂O₃ forming Fe₃O₄@Al₂O₃ core-shell magnetic nanoparticles and functionalized with PAN and SDS. FCD was synthesized from pineapple juice through hydrothermal carbonization. For copper determination, aliquots of wine, the FMNP dispersion, and Britton-Robinson buffer (pH = 4.0) were mixed under stirring to allow the adsorption of copper by FMNP. Cu-FMNP complex was attracted by a niobium magnet and, after discarding the non-magnetic material, the copper(II) ions were eluted with an FCD dispersion before fluorescence quenching measurements. The proposed method presented a linear range from 0.020 to 0.100 mg L^-1 (r² = 0.9953), RSD (intraday) < 3.0%, and recovery rates from 96 to 105 %. FMNP and FCD properties permitted extraction/preconcentration/determination of copper within 1 min with an enrichment factor of nine and without prior sample treatment.

Keywords: Analytical sample pretreatment; Fluorescent carbon dots; Magnetic nanoparticles; Magnetic solid-phase extraction; Red wines; Wine analysis.

MeSH terms

Adsorption
Carbon
Copper / analysis
Magnetite Nanoparticles*
Solid Phase Extraction
Wine*

Substances

Magnetite Nanoparticles
Carbon
Copper