Synergistic effect of MoS2 and diamond nanoparticles in electrochemical sensors: determination of the anticonvulsant drug valproic acid

The authors describe an electrochemical sensor based on the use of diamond nanoparticles (DNPs) and molybdenum disulfide (MoS2) platelets. The sensor was applied to the voltammetric determination of the anticonvulsant valproic acid which was previously derivatized with ferrocene. The MoS2 platelets...

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Detalles Bibliográficos
Autores: Petit Domínguez, María Dolores, Quintana Mani, María del Carmen, Pozo Vázquez, María del, Cuadrado Sánchez, Isabel, Parra Alfambra, Ana María, Casero Junquera, María Elena, Vázquez, Luis
Tipo de recurso: artículo
Fecha de publicación:2018
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/710249
Acceso en línea:http://hdl.handle.net/10486/710249
https://dx.doi.org/10.1007/s00604-018-2793-7
Access Level:acceso abierto
Palabra clave:Atomic force microscopy (AFM)
Diamond nanoparticles
Differential pulse voltammetry (DPV)
Electrochemical impedance spectroscopy (EIS)
Electrochemical sensor
Molybdenum disulfide
Valproic acid
Química
Descripción
Sumario:The authors describe an electrochemical sensor based on the use of diamond nanoparticles (DNPs) and molybdenum disulfide (MoS2) platelets. The sensor was applied to the voltammetric determination of the anticonvulsant valproic acid which was previously derivatized with ferrocene. The MoS2 platelets were obtained by an exfoliation method, and the DNPs were directly dispersed in water and subsequently deposited on a glassy carbon electrode (GCE). The sensor response was optimized in terms of the solvent employed for dispersing the MoS2 nanomaterial and the method for modifying the GCE. Sensors consisting of a first layer of MoS2 dispersed in ethanol/water and a second layer of DNPs give better response. The single steps of sensor construction were characterized by atomic force microscopy and electrochemical impedance spectroscopy. The differential pulse voltammetric response of the GCE (measured at +0.18 V vs. Ag/AgCl) was compared to that of sensors incorporating only one of the nanomateriales (DNPs or MoS2). The formation of a hybrid MoS2-DNP structure clearly improves performance. The GCE containing both nanomaterials exhibits high sensitivity (740 µA ⋅ mM−1 ⋅ cm−2), a 0.27 μM detection limit, and an 8% reproducibility (RSD). The sensor retained 99% of its initial response after 45 days of storage