Publications by authors named "Maria H A Feitosa"

This study reports the development and implementation of a straightforward, rapid, and cost-effective voltammetric technique for piroxicam (PIR) detection at nanomolar concentrations in biological and environmental samples. The method involved the use of a screen-printed electrode (SPE) enhanced with a combination of Printex L6 carbon (PL6C) and polyaniline-based activated carbon (PAC) on a chitosan film crosslinked with epichlorohydrin (CTS:EPH). The detection was carried out using square-wave adsorptive anodic stripping voltammetry (SWAdASV) in a 0.

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Nifedipine, a widely utilized medication, plays a crucial role in managing blood pressure in humans. Due to its global prevalence and extensive usage, close monitoring is necessary to address this widespread concern effectively. Therefore, the development of an electrochemical sensor based on a glassy carbon electrode modified with carbon nanofibers and gold nanoparticles in a Nafion film was performed, resulting in an active electrode surface for oxidation of the nifedipine molecule.

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Article Synopsis
  • The study presents a new flow injection analysis (FIA) system for measuring uric acid (UA) and caffeine (CAF) simultaneously, utilizing a cathodically pretreated boron-doped diamond electrode (CPT-BDD) with multiple-pulse amperometry (MPA).
  • Under specific optimized conditions, two distinct oxidation peaks were identified for UA and CAF, allowing for accurate concentration measurements with low detection limits.
  • The method showed high reliability, stability, and resistance to interference from common substances in environmental samples, achieving recovery rates between 98% and 104%.
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This work reports the development and application of a simple, rapid and low-cost voltammetric method for the determination of 3-methylmorphine at nanomolar levels in clinical and environmental samples. The proposed method involves the combined application of a glassy carbon electrode modified with reduced graphene oxide, chitosan and bismuth film (Bi-rGO-CTS/GCE) via square-wave voltammetry using 0.04 mol L Britton-Robinson buffer solution (pH 4.

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