Emerging viruses are a major public health problem. Most zoonotic pathogens originate in wildlife, including human immunodeficiency virus (HIV), influenza, Ebola, and coronavirus. Severe acute ...respiratory syndrome (SARS) is a viral respiratory illness caused by a coronavirus called SARS-associated coronavirus (SARS-CoV). Viruses are charged colloidal particles that have the ability to adsorb on surfaces depending on pH. Their sorptive interaction with solid particles has important implications for their behavior in aquatic environments, soils, sewage sludge, and other solid materials and their removal or concentration by water treatment processes.
Current state of knowledge on the potential of wastewater surveillance to understand the COVID-19 pandemic is reviewed. This study also identified wastewater irrigation systems with a higher risk of COVID-19 transmission. Emphasis was placed on methodologies for the detection and quantification of SARS-CoV-2 in wastewater.
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•Evidence for the presence of COVID-19 in wastewater•Detection methods and prevalence of viruses in wastewater•Knowledge needs for public health.•Recommendations on research and investigation priorities
•Methods of green synthesis of (NPs) using plant extract were reviewed.•Properties and characterization techniques of nanoparticles were presented.•Shape and size of green synthesized (NPs) via each ...plant have been compared.•Different utilizations of green synthesized (NPs) were inspected.•Future viewpoint of utilizations of green synthesis of (NPs) was studied.
The Nano-biotechnology represents the intersection of nanotechnology and biotechnology and is a promising field of nanotechnology. Recently, the need of making biocompatible nanoparticles for different applications in various areas by eco-friendly technologies in materials science became significant. Today, green synthesis of different nanoparticles NPs has been broadly examined. Biological synthesis of nanoparticles has evolved as a promising substitute to traditional synthesis methods for producing nanoparticles using unicellular and multicellular biological entities such as actinomycetes yeast, bacteria, viruses, plants, and fungus. In this paper, we provide a general overview on properties, synthesis methods and applications of nanoparticles NPs prepared from plant extract. Indeed, different techniques of green synthesis of NPs by plant extract were discussed and presented. The properties of synthesized NPs, in particular shape and size, were discussed and their applications have been also investigated. Furthermore, the future perspective of green synthesis of NPs and their applications were expressed.
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•Electrochemical detection of amoxicillin (AMX)•Types of chemically modified electrodes for AMX detection.•Indirect electrochemical methods for AMX analysis.•Analysis of Amoxicilin in ...several real samples.
Amoxicillin (AMX) is among the most successful antibiotics used for human therapy. It is used extensively to prevent or treat bacterial infections in humans and animals. However, the widespread distribution and excess utilization of AMX can be an environmental and health risk due to the hazardous potential associated to its pharmaceutical industries effluents. Besides, their extensive use in food animal production may result in some undesirable residues in food, e.g. meat, eggs and milk. Consequently, at high enough concentrations in biological fluids, AMX may be responsible of various diseases such as nausea, vomiting, rashes, and antibiotic-associated colitis. For this reason, the detection and quantification of amoxicillin in pharmaceuticals, biological fluids, environmental samples and foodstuffs require new electroanalytical techniques with sensitive and rapid measurement abilities. This review discusses recent advances in the development of electrochemical sensors and bio-sensors for AMX analysis in complex matrices such as pharmaceuticals, biological fluids, environmental water and foodstuffs. The main electrochemical sensors used are based on chemically modified electrodes involving carbon materials and nanomaterials, nanoparticles, polymers and biological recognition molecules.
This paper reports on the fabrication of material comprised of chitosan stabilized silver nanoparticles on the carbon paste and its electro-catalytic reduction toward 4-nitroaniline. The synthesized ...material was obtained when AgNO3 was mixed with chitosan as a stabilizing agent and NaBH4 as a reducing agent. The developed Chitosan-AgNPs has been confirmed using UV–Vis spectroscopy, X-Ray diffraction analysis, scanning electron microscopy (SEM) and infrared spectroscopy. The synthesized chitosan-Ag NPs exhibit particle size around 51 nm. To build a voltammetric sensor (Chitosan-Ag NPs/CPE), a carbon paste electrode has immersed in the liquid suspension of chitosan-Ag NPs, thus, it could be employed for electro-catalytic reduction of 4-NA in 0.1 M Britton-Robinson buffer solution (B-R, pH 2). Therefore, the reduction over-potential of 4-NA shifted from −752.26 mV at CPE to −304 mV at chitosan-Ag NPs/CPE, and then showing a surface controlled process with the catalytic rate constant (Kcat) of 0.125 × 10−3 M−1 s−1 and a coefficient of diffusion (D) of 2.20 × 10−6 cm2 s−1 with an enhanced current response. Under optimized conditions, the electro-catalytic reduction peak current of 4-NA increased linearly with increasing of 4-NA concentration over the range of 1 μM to 0.5 mM (R2 = 0.9866) with a detection limit of 0.86 μM (3 × Sb/P).
•CS@Ag/CPE has excellent electrocatalytic activity toward p-NA reduction.•The catalytic effect was studied using cyclic voltammetry and chronoamperometry.•All parameters affecting the detection of p-nitroaniline were optimized.•The results indicated the efficiency of proposed electrode to determine p-NA using DPV.
The purpose of this paper is to fabricate graphene oxide (GO) from carbon rods of spent (ZnC) batteries using a new optimized approach in electrochemical applications. The proposed method-based ...sonication for the recycling of carbon rods was adopted as a fast and economical process via a less aggressive pathway. The energy reaction time and explosion problems were avoided by the proposed protocol. The waste graphite powder (carbon rods) and the powder produced by the developed method-based sonication (SGO) were characterized by UV–Visible, XRD, FTIR and SEM. The electrochemical performance of the prepared SGO was evaluated by cyclic voltammetry (CV) and current-voltage (I–V) techniques. The results revealed that SGO has a higher electrocatalytic property compared to the graphene oxide by the standard Hummers method (HGO).
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∙Sonication-assisted oxidation and exfoliation process was recycled for graphene oxide (SGO) production.∙The carbon powder of (ZnC) batteries rods and its graphene oxide (SGO) were characterized.∙The energy and reaction time along with explosion problems were avoided by the proposed approach.∙Electrochemical performances of SGO were investigated and compared to the Hummers graphene oxide (HGO).
•COVID-19 infection poses a serious risk to human life by causing acute lung damage.•Various techniques used to identify and quantify COVID-19 infection.•Major challenges for containing the spread of ...COVID-19 is the ability to identify asymptomatic cases.•Currently available diagnostic methods, biosensing technology developed during COVID-19 infection.
The technologies used for coronavirus testing consist of a pre-existing device developed to examine different pathologies, such as bacterial infections, or cancer biomarkers. However, for the 2019 pandemic, researchers knew that their technology could be modified to detect a low viral load at an early stage. Today, countries around the world are working to control the new coronavirus disease (n-SARS-CoV-2). From this perspective, laboratories, universities, and companies around the world have embarked on a race to develop and produce much-needed test kits. This review has been developed to provide an overview of current trends and strategies in n-SARS-CoV-2 diagnostics based on traditional and new emerging assessment technologies, to continuous innovation. It focuses on recent trends in biosensors to build a fast, reliable, more sensitive, accessible, user-friendly system and easily adaptable technology n-SARS-CoV-2 detection and monitoring. On the whole, we have addressed and identified research evidence supporting the use of biosensors on the premise that screening people for n-SARS-CoV-2 is the best way to contain its spread.
The widespread use of antibiotics has contributed to the control of disease and the nutritional well-being of livestock. Antibiotics reach the environment via excretions (urine and feces) from human ...and domestic animals, through non proper disposal or handling of unused drugs. The present study describes a green method for the synthesis of silver nanoparticle (AgNPs) using cellulose extracted from Phoenix dactylifera seed powder via mechanical stirrer method for the electroanalytical determination of ornidazole (ODZ) in milk and water samples. The cellulose extract is used as the reducing and stabilizer agent for the synthesis of AgNPs. The obtained AgNPs were characterized by UV–Vis, SEM and EDX, presenting a spherical shape and an average size of 48.6 nm. The electrochemical sensor (AgNPs/CPE) was fabricated by dipping a carbon paste electrode (CPE) in the AgNPs colloidal solution. The sensor shows acceptable linearity with ODZ concentration in the linear range from 1.0 × 10−5 to 1.0 × 10−3 M with a limit of detection (LOD =3S/P) and quantification (LOQ =10S/P) of 7.58 × 10−7 M and 2.08 × 10−6 M respectively.
•Extraction of cellulose from Phoenix dactylifera seed and their characterization.•Utilization of the extracted cellulose in the synthesis of silver nanoparticles (AgNPs).•Preparation of new sensor based on synthesized AgNPs, to evaluate the electrocatalytic behavior of ODZ.•Electrochemical detection of ODZ in commercial milk and water samples using the proposed method.
In this study, a material comprised of chitosan stabilized silver nanoparticles on the carbon paste electrode (CS-SNPs/CPE) is used as an electrochemically active material for the determination of ...p-nitroaniline (p-NA) in neutral medium by differential pulse voltammetry (DPV). A chemical process is used to synthesize silver nanoparticles using chitosan and sodium borohydride as stabilizer and reducing agent respectively at room temperature. Characterization of the end product using UV–Vis spectroscopy verified the presence of silver nanoparticles. The silver nanoparticles were shown to have an average size of 50nm by X-ray diffraction analysis. The electrochemical characterization showed that the CS-SNPs/CPE exhibits high electroanalytic activity that can be harnessed for sensor construction and related applications. The as developed sensor exhibited a lower detection limit of 5nM towards the p-NA reduction in the linear range of 7nM to 1μM (R2=0.986). The CS-SNPs/CPE was then extended for the determination of p-NA in real samples such as wastewater. All these studies confirmed that the chitosan stabilized silver nanoparticles on the carbon paste electrode are a potential candidate in the field of electrochemical sensing.
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•The synthesis of CS-Ag nanoparticles was carried out using chemical method.•The proposed electrochemical sensor was reported for p-NA detection using DPV method.•The outstanding analytical performance was demonstrated in detecting p-NA in water.•The constructed sensor holds low detection limit of p-NA under optimized conditions.
In the last few decades, pharmaceuticals, credited with saving millions of lives, have emerged as a new class of environmental contaminants. These compounds can have both chronic and acute harmful ...effects on aquatic ecosystems and consequently on human health. Therefore, there is an urgent need for the development of extremely sensitive, portable, and low-cost devices to perform analysis. In the present review article, recent reports on the application of various voltammetric and photo-electrochemical techniques using different electrode materials for the determination of antibiotic Ciprofloxacin (CIPRO) are reported. This review provides an insight into direct and indirect electrochemical approaches as well as the photoelectrochemical methods used for the determination of CIPRO. Emphasis is put on the applications of unmodified and modified carbon-based electrodes considering the modifier, supporting electrolytes, analytical method, concentration range, limit of detection, and real matrices. Carbon-based electrodes are the most used materials attributed to their commercial availability, reduced cost, high chemical stability, and non-toxicity.
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•Antibiotics have emerged as a new class of environmental contaminants.•Recent carbon-based electrodes with their performances are summarized.•Electrochemical application for each modified/unmodified electrode is briefly discussed.•Direct and indirect approaches for Ciprofloxacin monitoring are discussed.
The development of nanoparticle research has grown considerably in recent years. One of the reasons for the considerable current interest in nanoparticles is because such materials frequently display ...unusual physical (structural, electronic, magnetic, and optical) and chemical (catalytic) properties. The development of nanomaterials is of interest to the scientific community and industrial companies. Different methods (physical, chemical, and biological) allow their manufacture. In particular, a major effort has been devoted to the development and improvement of synthesis methods in order to obtain nano-objects of controlled size and shape, a necessary pre-requisite to their organization, and to the study of their intrinsic and collective properties.
Reviews play an important role in keeping interested parties up to date on the current state of the research in any academic field. This review aims to focus on the development of nanoparticles and stabilization with adsorbed/covalently attached ligands in solution phase since these factors are deeply related to the origins of the particles’ stability, the media to which they are exposed, and the involved applications. This study also examines the factors that influence the synthesis of nanoparticles. It aims to provide an overview of existing electrochemical sensors, particularly those that operate with nanomaterial-based electrode modifications for p-nitroaniline (PNA) determination and to propose guidelines for related research and development activities. Emphasis was placed on the procedure for the analysis of PNA in water samples using nanosilver-based electrodes.
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•Controlling the synthesis and assembly of nanostructure are discussed.•Metal−Support interactions on different types of metal species are stated.•PNA is a ubiquitous contaminant in the environment up to 100 mg L−1.•Procedures for PNA analysis in water using nanosilver-based electrodes are discussed.