Search

Electrochemical sensors to quantify concentrations of emerging pollutants have attracted great attention from the industry and scientific community. Nanomaterials such as carbon black have been applied in sensors to identify substances that are toxic to the environment and human health due to their excellent electroanalytical properties. The aim of the study was to develop a novel electrochemical sensor for the endocrine disruptor hormone determination. To our knowledge, for the first time the synthesis of material based on carbon black containing immobilized palladium nanoparticles, with the application for the hormone ethinylestradiol, is reported in the literature. The material was synthesized, characterized, and applied to the determination in tap water and human urine of the synthetic hormone 17α‐ethinylestradiol (EE2), which is currently considered an emerging pollutant. The morphology, structure and electrochemical performance of the sensors were characterized by scanning electron microscopy (SEM) and cyclic voltammetry (CV). Differential pulse voltammetry (DPV) in sodium phosphate buffer solution at pH 5.0 allowed the generation of a method to quantify the concentration of 17α‐ethinylestradiol in a linear range of 0.5–119.0 μmol L−1, obtaining 81.0 nmol L−1 of calculated limit of detection (LOD). The system was efficient in detecting 17α‐ethinylestradiol in real urine samples and showed no interferences for ascorbic acid, uric acid, progesterone, and dopamine. It is noteworthy that the results obtained showed good recovery values, considering that the urine samples were not previously treated or pre‐concentrated, which suggests the development of an electrochemical sensor that works in situ and in real time to monitor relevant substances in the control clinical and environmental, with the possibility of point‐of‐care analyses. [ABSTRACT FROM AUTHOR]

Towards the development of miniaturised and low‐cost sensors for heavy metals detection in water, herein we describe an electrochemical sensor for the co‐detection of lead and cadmium. The sensor was developed using screen‐printed electrode modified with a composite of poly(propylene imine) dendrimer and carbon black. The electrode was modified by drop casting of the carbon black and electrodeposition of the poly(propylene imine) dendrimer. This modified electrode (sensor) was characterised by cyclic voltammetry and electrochemical impedance spectroscopy, revealing improved electrochemical performances. Square wave anodic stripping voltammetry (SWASV) was used to achieve the simultaneous detection of Pb(II) and Cd(II) at trace level, obtaining satisfactory LOD of 3.6 ppb and 15.3 ppb respectively; and sensitivity of 0.49 μA/ppb and 0.57 μA/ppb in tap water. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA) is an environmental endocrine disrupting chemical, which can lead to various adverse health effects. Aiming to develop effective tools for the detection of BPA, this work reports a low cost and stable film based on casein (CAS) and Carbon Black (CB). The proposed material (CAS‐CB) showed structures of CAS surrounded by CB agglomerates observed by Scanning Electron Microscopy while Fourier Transform Infrared Spectroscopy analysis illustrated characteristic bands of casein. Cyclic Voltammetry (CV) and linear sweep voltammetry (LSV) were used to investigate the electrochemical behavior of BPA using the CAS‐CB. Under optimal conditions, LSV detection presented a limit of detection of 0.25 μmol L−1 in a linear range from 0.49 to 24 μmol L−1. Additionally, the working electrode (GC) modified by the proposed film (CAS‐CB) was applied for BPA sensing in environmental and milk samples. The results showed recoveries between 95.4 to 114 % attesting the efficiency of this new material, which has simplicity in the preparation, high conductivity, and adsorption capability. [ABSTRACT FROM AUTHOR]

The paper reports the development of a new sensor based on Printex L6 (CPL6) carbon black modified with copper oxides (CuO/Cu2O) nanoparticles and its application towards the determination of Propylparaben (PP). In fact, it is the first report of its kind in the literature. The sensor was produced through the dispersion of CPL6 in dimethylformamide on glassy carbon electrode surface followed by CuO/Cu2O electrodeposition. The conditions of electrodeposition investigated included time and solution concentration of Cu (II). Morphological, structural and electrochemical characterizations of the sensor were performed. Under optimal conditions, wide linear range (1.0 to 35.0 μmol L−1) was obtained in the detection of PP. The detection limit obtained was 0.46 μmol L−1 (S/N=3). The CuO/Cu2O‐CPL6/GCE sensor was found to be as sensitive as the high performance liquid chromatography in the determination of PP in both cosmetic and river water samples, in addition to being reproducible and stable. [ABSTRACT FROM AUTHOR]

Abstract: Detection of traces from pharmaceutical drugs such as antibiotics in drinking water and foodstuff is essential for guaranteeing human health in some environments, and this has to be done with low cost technologies to be widely deployed in public services and industry. In this paper, we describe an ultralow cost (

In this work, a simple and highly selective voltammetric method was developed for the simultaneous determination of paracetamol (PCT) and codeine (COD) in pharmaceuticals and human body fluids employing a glassy carbon electrode modified with carbon black (CB) and nickel oxide nanoparticles (NiONPs) within a dihexadecylphosphate (DHP) film. Using square-wave voltammetry (SWV), a separation of ca. 550 mV between the oxidation peak potentials of PCT and COD was obtained. The simultaneous determination of PCT and COD presented a linear concentration range from 3.0 to 47.8 µmol L−1 for PCT and from 0.83 to 38.3 µmol L−1 for COD. [ABSTRACT FROM AUTHOR]

Both screen-printed electrodes modified with a dispersion of carbon black (CB) and solid paste electrodes prepared using a nanostructured CB were developed and characterized. Indeed, increasing the peak currents and/or their shifting to negative potentials were observed, exhibiting efficient electrocatalytic activity towards nitrite oxidation with high sensitivity and low detection limit. Solid carbon paste electrodes (SCPEs) and solid carbon black paste electrodes (SCBPEs) were challenged in amperometric mode with nitrite since detection limit reached is 65 and 5 nM respectively. Nitrate was first reduced to nitrite in reductor column, then detected on SCBPEs. Nitrate and nitrite were determined in real samples. [ABSTRACT FROM AUTHOR]