Publications by authors named "Benjamin Viada"

An innovative supramolecular architecture is reported for bienzymatic glucose biosensing based on the use of a nanohybrid made of multi-walled carbon nanotubes (MWCNTs) non-covalently functionalized with a Schiff base modified with two phenylboronic acid residues (SB-dBA) as platform for the site-specific immobilization of the glycoproteins glucose oxidase (GOx) and horseradish peroxidase (HRP). The analytical signal was obtained from amperometric experiments at - 0.050 V in the presence of 5.

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This work presents for the first time the systematic preparation of a novel carbon nanotube-MCM-41 hybrid employing the mesoporous material MCM-41 as a successful dispersant for multiwall carbon nanotubes (MWCNTs). Relevant dispersion variables such as the amount of MWCNTs, MCM-41 concentration, and sonication time were optimized through a central composite design (CDD)/response surface methodology (RSM). Several solvents were evaluated and ,-dimethylformamide (DMF) was selected because it allowed reaching stable dispersions with very good electrochemical response.

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The interfacial behaviour of the amphiphilic drug hexadecyl phosphocholine (HePC, also called miltefosine) was analysed by cyclic voltammetry applied at the water/1,2-dichloroethane interface. HePC is the only oral drug currently approved for the treatment of visceral, mucosal  and cutaneous leishmaniasis. Because of its amphiphilic character, it can interact with biological membranes, solubilizing their compounds and leading to cell disruption.

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Per- and polyfluoroalkyl substances (PFAS) are a category of persistent environmental contaminants that have been linked to health issues in humans. In this work, we investigate the detection of perfluorooctanesulfonate (PFOS-), one such PFAS, by ion-transfer voltammetry at an array of microinterfaces between two immiscible electrolyte solutions (μITIES). Cyclic voltammetry, differential pulse voltammetry and differential pulse stripping voltammetry (DPSV) indicated the ion-transfer behaviour and detection of PFOS-, with the latter enabling detection at picomolar concentrations.

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Perfluoroalkyl acids (PFA) are amphiphilic surfactants widely used in industry with several commercial applications. An important feature of these compounds is their non-biodegradability and their tendency to bio-accumulate in the environment, which has led to these compounds being considered among the most persistent pollutants worldwide. Many studies have provided evidence of their toxic effect on humans and wildlife.

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