A new tool for the determination of humic substances in natural waters: pulsed voltammetry approach

Humic substances (HS) in natural waters can be determined with a new, simple and sensitive method based on their influence on the background current in a differential pulse - adsorptive cathodic stripping voltammetry. The proposed method, termed PB-HS (pulsed background - humic substances) is discus...

Descripción completa

Detalles Bibliográficos
Autores: Marcinek , Saša, Galceran i Nogués, Josep, Ciglenečki, Irena, Omanović, Dario
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2023
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:10459.1/464802
Acceso en línea:https://doi.org/10.1016/j.talanta.2023.124547
https://hdl.handle.net/10459.1/464802
Access Level:acceso abierto
Palabra clave:Humic substances
Differential pulse adsorptive cathodic stripping voltammetry
Seawater
Estuary
Descripción
Sumario:Humic substances (HS) in natural waters can be determined with a new, simple and sensitive method based on their influence on the background current in a differential pulse - adsorptive cathodic stripping voltammetry. The proposed method, termed PB-HS (pulsed background - humic substances) is discussed in detail, including its application in natural samples from the Krka River estuary. The method was additionally compared with absorbance measurements as well as with the typical electrochemical HS quantification in natural waters based on HS complexation with molybdenum (Mo). A good correlation between methods was observed, with PB-HS showing slightly better sensitivity to humic compounds than classical spectrophotometry. Higher HS concentrations measured with the Mo-method may be due to the enhanced hydrophobicity reached at pH 2 that is required by the method. Advantages of the proposed PB-HS method, compared to existing voltammetric methods for HS quantification, are that it does not require any reagent addition (except buffer) and that it can be used at the natural pH of water as well as in a wide salinity range, which is crucial for its application in estuarine waters.