Publications by authors named "Maisa Azevedo Beluomini"

The development and application of an electrochemical sensor is reported for detection of poly(3-hydroxybutyrate) (P3HB) - a bioplastic derived from agro-industrial residues. To overcome the challenges of molecular imprinting of macromolecules such as P3HB, this study employed methanolysis reaction to break down the P3HB biopolymer chains into methyl 3-hydroxybutyrate (M3HB) monomers. Thereafter, M3HB were employed as the target molecules in the construction of molecularly imprinted sensors.

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The triphasic interaction of gases with electrode surfaces immersed in aqueous electrolyte is crucial in electrochemical technologies (fuel cells, batteries, sensors). Some microporous materials modify this interaction locally via triphasic storage capacity for gases in aqueous environments linked to changes in apparent oxygen concentration and diffusivity (as well as activity and reactivity). Here, a nanoparticulate polymer of intrinsic microporosity (PIM-1) in aqueous electrolyte is shown to store oxygen gas and thereby enhance electrochemical signals for oxygen reduction in aqueous media.

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In this work, an electrochemical sensor was developed for the determination of naphthalene (NaP) in well water samples, based on a glass carbon electrode (GCE) modified as a nanocomposite of manganese oxides (MnO) and COOH-functionalized multi-walled carbon nanotubes (MWCNT). The synthesis of MnO nanoparticles was performed by the sol-gel method. The nanocomposite was obtained by mixing MnO and MWCNT with the aid of ultrasound, followed by stirring for 24 h.

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Monitoring sulfur in biodiesel is of fundamental importance because even in low concentrations, it can harm the operation of the engine parts and increase the emission of toxic gases and particulate material. Hence, a simple, quick and sensitive adsorptive stripping voltammetry (AdSV) method based on a silver solid amalgam electrode (AgSAE) was developed to determine sulfur in biodiesel. The novel electrochemical method was evaluated through the linear sweep adsorptive stripping voltammetry (LSAdSV), square wave adsorptive stripping voltammetry (SWAdSV) and differential pulse adsorptive stripping voltammetry (DPAdSV) in a NH/NH buffer solution (pH 9.

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In this study, an electrochemical sensor was designed for the detection of narirutin using three-dimensional nanostructured porous nickel on screen-printed electrode (3DnpNi/SPE). The modified electrode was successfully synthesized by the dynamic hydrogen bubble template method. The 3DnpNi/SPE was characterized by spectroscopic, microscopic, and electrochemical methods.

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Article Synopsis
  • Lactose (LAC) is a crucial sugar found in milk, serving as an important quality indicator in dairy products and impacting human and animal health.
  • An innovative voltammetric sensor was developed using an electropolymerized pyrrole molecularly imprinted polymer on a graphite electrode, enhancing LAC detection capabilities.
  • The sensor demonstrated high sensitivity and selectivity in detecting LAC in various milk types, with promising analytical performance characterized by dynamic linear ranges and a low detection limit.
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This paper reports on the development of an amperometric method for the determination of myo-inositol. The method involves coating of a glassy carbon electrode (GCE) with a molecularly imprinted polymer (MIP) and reduced graphene oxide (RGO) that was modified with nickel nanoparticles (NiNPs). The MIP was prepared by electropolymerization of pyrrole on the surface of the GCE in the presence of myo-inositol molecules.

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An electrochemical sensor for D-mannitol based on molecularly imprinted polymer on electrode modified with reduced graphene oxide decorated with gold nanoparticles was developed in this present work. The sensor was constructed for the first time via the electropolymerization of o-phenylenediamine (o-PD) over a surface containing reduced graphene oxide (RGO) and gold nanoparticles (AuNP) in the presence of D-mannitol molecules. The surface modification with AuNP/RGO-GCE facilitated the charge transfer processes of [Fe(CN)], which was used as an electrochemical probe.

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A glassy carbon electrode chemically modified with nickel nanoparticles coupled with reversed-phase chromatography with pulsed amperometric detection was used for the quantitative analysis of furanic aldehydes in a real sample of sugarcane bagasse hydrolysate. Chromatographic separation was carried out in isocratic conditions (acetonitrile/water, 1:9) with a flow rate of 1.0 mL/min, a detection potential of -50 mV vs.

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