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This work reports the construction of screen‐printed electrode (SPE) modified with carbon black (CB) and magnetic Fe3O4 nanoparticles coated with molecularly imprinted polymer (mag@MIP) based on an alternative low‐cost approach. The proposed device was used for the sensitive and selective voltammetric determination of the antibiotic ciprofloxacin. The results obtained from cyclic voltammetry pointed to the improvement of the SPE response toward the irreversible oxidation of ciprofloxacin after the modification of the electrode surface with CB‐based film and the magnetic preconcentration of mag@MIP containing adsorbed ciprofloxacin molecules. Compared to the non‐molecularly imprinted sensor (mag@NIP), the presence of cavities selective for ciprofloxacin recognition in the mag@MIP nanoparticles accounted for the improvement in analytical signal of the molecularly imprinted sensor. The application of differential pulse voltammetry for ciprofloxacin determination yielded a linear response in the concentration range of 0.5 to 7.0 μmol L−1. The repeatability and interference tests results showed that the proposed electrochemical sensor has good measurement accuracy and selectivity. The proposed device was applied for the voltammetric determination of ciprofloxacin in river water and synthetic urine samples, where recovery rates close to 100 % were recorded for all the samples. The quantification data obtained from the application of the proposed voltammetric method were quite consistent with those of the HPLC reference method. [ABSTRACT FROM AUTHOR]

In this work, we reported a new strategy based on DNA strands hydrolysis in combination with the employment of functionalized carbon black modified screen‐printed electrode (f‐CB/SPE) for guanine detection. Using glass microbeads as a solid substrate of ssDNA probe fixation, and under appropriate conditions of temperature, time, and hydrochloric acid concentration, DNA hydrolysis has been successfully used to release the guanine, allowing its oxidation at f‐CB/SPE using differential pulse voltammetry. The selectivity was successfully tested with a non‐complementary sequence, and a detection limit of 0.7 nM of the target DNA has been reached. [ABSTRACT FROM AUTHOR]

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]

An electrochemical sensor using glassy carbon electrode modified with carbon black within a poly(allylamine hydrochloride) film is proposed in this work. The novel sensor was characterized by scanning electron microscopy, electrochemical impedance spectroscopy, and cyclic voltammetry using the redox probe Fe(CN)63−/4−. The sensor was applied for the simultaneous determination of dopamine (DA), paracetamol (PAR), amlodipine (AML), and rosuvastatin (RSV). The quantification of all four analytes was carried out by linear sweep voltammetry and presented a linear concentration range for all analytes from 1.0 to 90 μmol L−1, with limit of detection of 0.55, 1.3, 5.7, and 3.0 μmol L−1 for DA, PAR, AML, and RSV, respectively. This sensor was successfully applied in the simultaneous determination of these analytes in environmental, pharmaceutical, and biological samples. [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]

The recent trend of using sustainable disinfectants in water treatment sector boosted the employment of chlorine dioxide (ClO2) as green disinfectant. Indeed, this disinfectant is characterised by several attractive features such as the working capability in a wide range of pH and the absence of harmful by‐products. These characteristics confer to chlorine dioxide a prominent position between the disinfectants, thus analytical tools for on‐site detection are needed to customize the water treatment. Herein, we described the development of an innovative and cost‐effective carbon black modified screen‐printed electrode for amperometric quantification of chlorine dioxide in standard solution and in swimming pool water. The carbon black as working electrode nanomodifier allowed for the detection of chlorine dioxide at low applied potential, with linear range of 0.05–20 ppm, and a detection limit of 0.01 ppm. The matrix effect evaluation as well as the recovery study demonstrated the capability of this sensor for a cost‐effective detection of chlorine dioxide in swimming pool water, paving the way for the use of miniaturised electrochemical sensors in water treatment field. [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]