Residual biomass of coffee as a binding agent in diffusive gradients in thin-films technique for Cd, Cu, Ni, Pb and Zn measurement in waters

Author(s)

Yabuki, Lauren N. M. ^[1] ; Menegario, Amauri A. ^[2] ; Gemeiner, Hendryk ^[2] ; Rolisola, Ana Marta C. M. ^[2] ; Gastmans, Didier ^[2] ; Williams, Paul N. ^[3]

Affiliation

^[1] Univ Estadual Paulista Unesp, Inst Geociencias & Ciencias Exatas, Av 24 A, 1515, BR-13506900 Sao Paulo - Brazil

^[2] Univ Estadual Paulista Unesp, Ctr Estudos Ambientais, Av 24 A, 1515, BR-13506900 Sao Paulo - Brazil

^[3] Queens Univ Belfast, Inst Global Food Secur, Sch Biol Sci, Belfast BT9 5BN, Antrim - North Ireland

• Document type: Journal article
• Source: Talanta; v. 205, DEC 1 2019.
• Web of Science Citations: 0

Abstract

Spent coffee grounds (SCG) immobilized in agarose gel are proposed as a novel binding agent for application in the Diffusive Gradients in Thin films (DGT) technique for the determination of Cd, Cu, Ni, Pb and Zn in waters. The SCG-agarose gel was characterized by Scanning Electron Microscopy, Energy Dispersive X-ray Spectrometry and Porosimetry by nitrogen adsorption. Elution of analytes from the binding agent was effectively performed with 2 mol L-1 HCl. The effects of key DGT parameters (e.g. immersion time, ionic strength and pH) were evaluated with a deployment of DGT devices (DGT-SCG) in synthetic solutions with ionic strengths between 0.005 mol L-1 and 0.1 mol L-1 and within a pH range of 3.5-8.0. The results were in excellent agreement with the predicted theoretical curve for mass uptake. Consistent results were found for solutions with ionic strengths between 0.005 mol L-1 and 0.1 mol L-1 and within a pH range of 3.5-8.0. The DGT-SCG performance was also evaluated in two spiked river water samples (Corumbatai and Piracicaba river) with satisfactory uptake values (CDGT-SCG/C-sol) between 0.74 and 1.53. The proposed DGT-SCG opens opportunities for using residual biomass as binding phase in the DGT technique, showing low costs in production and complying with ``green{''} technology approaches. (AU)

• FAPESP's process: 16/14227-5 - Climatic changes and environmental impacts in wetlands of Pantanal region (Brazil): quantification, control factors and long term temporal modeling
• Grantee: Adolpho José Melfi
• Support Opportunities: Research Program on Global Climate Change - Thematic Grants
• FAPESP's process: 18/17069-7 - Evaluation of the biogeoavailability of metals and semimetals in soils using the diffusive gradient in thin film technique
• Grantee: Amauri Antonio Menegário
• Support Opportunities: Regular Research Grants