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1.
Chemosphere ; 303(Pt 3): 135270, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35688198

RESUMO

The pharmaceutical science demand for sustainable and selective electrochemical sensors which exhibit ultrasensitive capabilities for the monitoring of different drugs. In an attempt to build a useful electrochemical sensor, we describe a most efficient method for the fabrication of NiO/ZnO nanocomposite through aqueous chemical growth method. The successfully synthesized NiO/ZnO nanocomposite is successfully employed to modify a glassy carbon electrode in order to build a sensitive and reliable electrochemical sensor for the detection of carbamazepine (CBZ), an anticonvulsant drug. The morphological texture, functionalities and crystalline structure of prepared nanocomposite were determined via FTIR, XRD, EDX, TEM, and SEM analysis. In order to examine the charge transfer kinetics, the cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to exploit the electrochemical properties of the synthesized nanocomposite. The NiO/ZnO nanocomposite exhibited excellent electron transfer kinetics and less resistive behavior than the individual NiO and ZnO nanoparticles. The differential pulse voltammetry and cyclic voltammetry tools were used for the fluent determination of CBZ. Certain parameters were optimized to develop an effective method including optimum scan rate 60 mV/s, potential range from 0.4 to 1.4 V and BRB as supporting electrolyte with pH 3. The developed sensor showed exceptional response for CBZ under the linear dynamic range from 5 to 100 µM. The limit of detection of proposed NiO/ZnO sensor for the CBZ was calculated to be 0.08 µM. The analytical approach of prepared electrochemical sensor was investigated in different pharmaceutical formulation with acceptable percent recoveries ranging from 96.7 to 98.6%.


Assuntos
Nanocompostos , Óxido de Zinco , Carbamazepina/análise , Técnicas Eletroquímicas/métodos , Eletrodos , Nanocompostos/química , Óxido de Zinco/química
2.
Chemosphere ; 303(Pt 3): 135170, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35640684

RESUMO

Over the past few decades, phenolic compounds have been broadly exploited in the industries to be utilized in several applications including polycarbonate plastic, food containers, epoxy resins, etc. One of the major compounds in phenolics is Bisphenol-S (BPS) which has dominantly replaced Bisphenol-A in several applications. Phenolic compounds are extensively drained into the environment without proper treatment and cause several health hazards. Thus, to tackle this serious problem an electrochemical sensor based on SnO2/GCE has been successfully engineered to monitor the low-level concentration of BPS in water samples. The fabrication of SnO2 nanoparticles (SnO2 NPs) was confirmed through FTIR, XRD, and TEM to examine the size, crystallinity, internal texture, and functionalities of the prepared material. The fabricated material was exploited as a chemically modified sensor for the determination of BPS in water samples collected from different sources. Under optimal conditions such as scan sweep 100 mV/s, PBS electrolyte pH of 6, potential window (0.3-1.3 V), the proposed sensor manifested an excellent response for BPS. The LOD of the present method for BPS was calculated as 0.007 µM, respectively. Moreover, the stability and selectivity profile of SnO2/GCE for BPS in the real matrix was examined to be outstanding.


Assuntos
Técnicas Eletroquímicas , Poluição Ambiental , Técnicas Eletroquímicas/métodos , Eletrodos , Polímeros de Fluorcarboneto , Limite de Detecção , Compostos de Estanho , Água
3.
Chemosphere ; 300: 134634, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35439494

RESUMO

The drastic increases in the concentration of heavy metals ions in the environment have become a serious concern for a number of years. Heavy metals pose serious impacts on human and aquatic life and cause severe health hazards. Amongst heavy metals, cadmium is known for its lethal effects on human health as it easily reacts with enzymes and creates free radicals in the biological system that causes carcinogenicity and other serious diseases. Thus, to tackle this challenge, TX-100 SnO2 nanoparticles based chemically modified sensor is introduced to assess the quantity of Cd+2 in the water system. The engineered SnO2 nanoparticles were electrochemically characterized through cyclic voltammetry and electrochemical impedance spectroscopy to ensure the better charge transfer kinetics and electrocatalytic properties of fabricated sensors. Under the optimized conditions e.g., scan rate 80 mV/s, PBS electrolyte pH 7, and potential window (-0.2 to -1.4 V), the engineered TX-100/SnO2/GCE-based sensor manifested a phenomenal response for cadmium ions in water media. The LOD and LOQ of developed TX-100/SnO2/GCE were calculated in the nanomolar range as 0.0084 nM and 0.27 nM. The recovery values of the proposed method for Cd+2 were found in an acceptable limit that witnesses the effectiveness of the fabricated sensor. Moreover, the excellent stability and anti-interference behavior of the sensor highlights its dynamic profile to be commercially utilized for the determination of Cd+2 ions in water bodies.


Assuntos
Metais Pesados , Nanopartículas , Cádmio , Técnicas Eletroquímicas/métodos , Eletrodos , Humanos , Nanopartículas/química , Octoxinol , Água
4.
Food Chem Toxicol ; 161: 112843, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35101578

RESUMO

The extensive use of pesticides for better yield of crops have become major human concern over the decades. Pesticides are widely used in the fields to kill weeds and pests on the vegetable and crops to improve the quality and yield of the food knowing the fact that pesticides residue in food are very lethal for human being. Amongst, the hazardous pesticides, mancozeb is widely applied in the protection of crops. Thus the quantification of mancozeb residue is of great importance. This study reports the electrochemical monitoring of mancozeb through tungsten oxide reduced graphene oxide (WO3/rGO) nanocomposite. The engineered nanocomposite was characterized though different analytical tools such as FTIR, XRD and TEM to examine crystallinity, internal texture and the size. The FTIR result confirm the functionalities of GO and WO3/rGO nanocomposite in finger print and functional group region. Through XRD analysis, the size of the WO3/rGO nanocomposite was calculated as 31.6 nm. While the TEM analysis was also exploited to examine the 2D texture of GO and nanometric size of the WO3/rGO. To ensure the conductive nature of the WO3/rGO nanocomposite, the glassy carbon electrode was modified and exploited for cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Under the optimal conditions, the modified sensor showed exceptional response for mancozeb. The linear dynamic range was set from 0.05 to 70 µM in BRB buffer of pH 4. The LOD and LOQ for proposed method was calculated as 0.0038 and 0.0115 µM. The analytical applicability of chemically modified sensor was investigated in real matrix of different vegetable samples and the recovery values were observed in acceptable range. The electrochemical examination of present work reveals that WO3/rGO nanocomposite can be an exceptional aspirant for the determination of mancozeb at commercial level.


Assuntos
Técnicas Eletroquímicas/instrumentação , Grafite/química , Maneb/química , Nanocompostos/química , Óxidos/química , Tungstênio/química , Zineb/química , Técnicas Eletroquímicas/métodos , Recuperação e Remediação Ambiental/instrumentação , Recuperação e Remediação Ambiental/métodos , Concentração de Íons de Hidrogênio
5.
Langmuir ; 37(10): 3214-3222, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33657802

RESUMO

2,4,6-Trichlorophenol (2,4,6 TCP) is one of the hazardous toxicants, which has severe impacts on the environment and human health. This study is designed to develop a highly sensitive and selective electrochemical sensor based on CuO nanostructures for the detection of 2,4,6 TCP. The CuO nanostructures were synthesized through an aqueous chemical growth method and characterized by versatile analytical techniques, for example, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, atomic force microscopy, energy-dispersive spectrometry, and X-ray diffraction. The characterization tools revealed a high crystalline nature, exceptional phase purity, nanoball morphology with an average size of around 18.7 nm for the CuO nanostructures. The synthesized material was used to modify a glassy carbon electrode (GCE) with the help of Nafion as a binder to improve its efficiency and sensitivity. The CuO/Nafion/GCE was proven to be a potential sensor for the determination of 2,4,6 TCP under optimized conditions at a scan rate of 70 mV/s, potential range of 0.1-1.0 V, and phosphate buffer of neutral pH as the supporting electrolyte. The linear range for 2,4,6 TCP was set from (1 to 120 µM) with a low limit of detection value calculated to be 0.046 µM. The developed sensor was effectively applied for water samples with acceptable recovery values from 95.9 to 100.6%.

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