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1.
Nanoscale ; 16(14): 7211-7224, 2024 Apr 04.
Article in English | MEDLINE | ID: mdl-38507273

ABSTRACT

Our study delves into the examination of an electrochemical sensor through both experimentation and mathematical analysis. The sensor demonstrates the ability to identify a specific antipsychotic medication, namely Chlorpromazine Hydrochloride (CPH), even at incredibly low concentrations, reaching the picomolar level. The identification process relies on the utilization of a Glassy Carbon Electrode (GCE) that has been modified with a ceria-doped zirconia (CeO2/ZrO2) nanocomposite. The nanocomposite was synthesized using the co-precipitation technique and extensively characterized through various analytical methods. It is crucial to detect the presence of CPH as an overdose can result in hyperactivity and severe bipolar disorders among both children and adults. The average size of the nanocomposite was estimated to be 10 nm. The electrode surface area after CeO2/ZrO2 modification of the GCE was found to be 0.059 cm2, which was significantly higher than the electrode surface area of the bare GCE (0.0307 cm2). The limit of detection and limit of quantification for CPH were calculated to be 99.3 pM and 3.010 nM, respectively, with the linear dynamic range of CPH detection found to be between 0.10 and 1.90 µM. The modified sensor electrode was tested on human urine samples with good recoveries and exhibited high selectivity, repeatability, reproducibility, and long-term stability. The experimental voltammograms and the simulated stochastic voltammograms exhibited a fair amount of agreement. Examination of the experimental findings alongside analytical and numerical solutions enables a comprehensive analysis of the factors influencing the outcome of electrochemical measurements. The precise findings can be leveraged for the development of efficient sensing devices for medical diagnostics and environmental monitoring.


Subject(s)
Electrochemical Techniques , Nanocomposites , Child , Humans , Reproducibility of Results , Electrochemical Techniques/methods , Carbon/chemistry , Nanocomposites/chemistry , Electrodes
2.
Chemosphere ; 354: 141708, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38521104

ABSTRACT

Organophosphorus pesticides, particularly profenofos (PF), pose a significant threat to the food supply and human health due to their persistence, toxicity, and resistance to natural breakdown processes. An urgent need exists for an environmentally friendly solution, and photocatalysis emerges as a practical, cost-effective option. However, challenges like poor light responsiveness and difficulties in material separation and reusability persist. To address these issues, we developed a nanocomposite consisting of graphite carbon nitride (g-C3N4) doped with polydopamine (pDA) through a hydrothermal synthesis method. This innovative nanocomposite was employed as a photocatalyst to degrade PF. Various analytical techniques, including UV-DRS, FT-IR, XRD, HR-TEM, and EDAX, were utilized to characterize the synthesized nanocomposite. The strategically modulated band gaps of the nanocomposite enable efficient absorption of UV light, facilitating the robust photocatalytic degradation of PF (96.4%). Our study explored photodegradation using different g-C3N4/pDA catalyst dosages, varied PF concentrations, and pH levels (3, 5, 9, and 11) under UV light. Our findings promise applications in wastewater management, offering an efficient catalyst for PF degradation. This marks a significant stride in addressing challenges related to pesticide pollution in the environment.


Subject(s)
Graphite , Indoles , Nanocomposites , Nitriles , Nitrogen Compounds , Pesticides , Polymers , Humans , Graphite/chemistry , Water , Organophosphorus Compounds , Spectroscopy, Fourier Transform Infrared , Nanocomposites/chemistry , Catalysis , Light
3.
Food Chem ; 439: 138073, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38029564

ABSTRACT

This study introduces an efficient electrochemical method for rapidly identifying the pathogen Pseudomonas aeruginosa (P. aeruginosa), which poses threats to individuals with compromised immune systems and cystic fibrosis. Unlike conventional techniques such as polymerase chain reaction, which fails to detect modifications in the resistant properties of microbes due to environmental stress, our proposed electrochemical approach offers a promising alternative. The characterisation analyses, involving microscopic and spectroscopic methods, reveal that the nanocomposite exhibits a crystalline structure, specific atomic vibrational patterns, a cubic surface shape, and distinct elemental compositions. This sensor demonstrates exceptional detection capabilities for P. aeruginosa, with a linear range of 1-23 CFU mL-1 and a low detection limit of 4.0 × 10-3 CFU mL-1. This research not only explores novel electrochemical techniques and the CoFe2O4/AgNPs nanocomposite but also their practical implications in food science, highlighting their relevance across various food samples, water, and soil.


Subject(s)
Metal Nanoparticles , Nanocomposites , Humans , Silver/chemistry , Pseudomonas aeruginosa , Electrochemical Techniques/methods , Cobalt/chemistry , Nanocomposites/chemistry , Metal Nanoparticles/chemistry
4.
Environ Pollut ; 343: 123189, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38123118

ABSTRACT

The misuse of antibiotics has become a concerning environmental issue, posing a significant threat to public health. Levofloxacin (LFX), a fluoroquinolone antibiotic, is particularly worrisome due to its detrimental impact on human health and the ecosystem. Therefore, the selective and accurate identification of LFX is of utmost importance. In this study, we have developed an electrochemical sensor based on cobalt-doped calcium phosphate (Co@CaHPO) for the sensitive and selective detection of LFX in various water samples. Under optimized conditions, the Co@CaHPO-modified glassy carbon electrode (GCE) exhibited exceptional electrochemical activity, low charge transfer resistance, and a fast electron transfer rate, outperforming the unmodified GCE. The proposed Co@CaHPO-modified GCE demonstrated remarkable electrochemical characteristics, including a wide linear range (0.3-460 µM) and a lower detection limit (0.151 µM) with high sensitivity (0.676 µAµM-1 cm2). This detection approach may enable the direct detection of LFX in the pharmaceutical environment. Furthermore, the resulting sensor exhibited good selectivity, excellent cyclic and storage stability, reproducibility, and repeatability. The practical application of this LFX sensor can be extended to various water samples, yielding reliable and satisfactory results.


Subject(s)
Levofloxacin , Nanospheres , Humans , Reproducibility of Results , Ecosystem , Carbon , Water , Electrodes , Limit of Detection
5.
Mater Sci Eng C Mater Biol Appl ; 113: 111010, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32487413

ABSTRACT

The measurement of renal function by important clinical parameters such as (Crt) clearance and glomerular filtration rate often goes wrong vis-à-vis the Crt level in human body. Hence, development of an accurate detection system over a wide range of Crt concentration in both blood and urine is medically essential. In this study, a new non-enzymatic electrochemical probe, carbon dots doped tungstic anhydride embedded on graphene oxide nanopanels (CDs/WO3@GO) is reported for picomolar-level Crt detection in blood and urine with a wide linear range (0.2-112.0 nM). The sensor is economical, reproducible, stable and interferents-free. The properties of CDs/WO3@GO were studied using various analytical techniques. The proposed electrochemical Crt sensor could be used as a sustainable alternative for diagnostic use.


Subject(s)
Carbon/chemistry , Creatinine/analysis , Electrochemical Techniques/methods , Graphite/chemistry , Nanocomposites/chemistry , Oxides/chemistry , Tungsten/chemistry , Creatinine/blood , Creatinine/urine , Electrodes , Humans , Limit of Detection , Quantum Dots/chemistry , Reproducibility of Results
6.
Ultrason Sonochem ; 62: 104871, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31806554

ABSTRACT

The fabrication of hetero structured materials with supercapacitor applications for industrial use remains a key challenge. This work reports a new supercapacitor material with high capacitance, comprising samaria and borazon (O3Sm2/BN) synthesized ultrasonically (40 ±â€¯3 kHz, 200 W). The successful synthesis, probable interfaces between O3Sm2 and BN and thermal stability of the nanocomposite were studied by UV-Vis. and FT-IR spectroscopies, X-ray diffraction (XRD) and thermo gravimetric analyses (TGA). The morphology of nanocomposite was investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Elemental mapping analysis and energy dispersive X-ray analysis (EDAX) confirmed the elements present in the material. This supercapacitor material shows a maximum discharge capacitance of 414 Fg-1 at 0.25 Ag-1 and an exceptional retention of specific capacitance (92.5%) in 5000 cycles. Such nanocomposite with better specific capacitance and charge/discharge rates makes it a right candidate as next generation supercapacitor, which certainly finds applications in various unconventional energy storage devices.

7.
Ultrason Sonochem ; 58: 104629, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31450371

ABSTRACT

Bisphenol A (BPA) is an endocrine-disrupting chemical which resembles structurally the hormone estrogen. Even a trace amount of BPA can bind estrogen receptors resulting in the inducement of reproductive disorders, cancers and problems related to sexual growth such as manliness in female and womanliness in male. So the determination of BPA in human and animal bodies is very essential. For this purpose, a new nanocomposite composed of ruthenium nanoparticles, polyaniline and graphitic carbon nitride (Ru0/PANI/g-C3N4) has been synthesized ultrasonically (40 ±â€¯3 kHz, 200 W). A modification on glassy carbon electrode (GCE) with the nanocomposite detects BPA in human and animal urine samples with wide linear range (0.01-1.1 µM) and the limit of detection is pico molar-level. The synthesized nanocomposite was characterized by Ultraviolet-Visible and Fourier Transform-Infra Red spectroscopies, thermo gravimetric analysis, transmission electron microscopy, X-ray diffraction study, energy dispersive X-ray analysis, and elemental mapping analysis. This sensing system is selective, stable and reusable, by which the detection of BPA in various physiological fluids is very much possible.


Subject(s)
Aniline Compounds/chemistry , Benzhydryl Compounds/urine , Electrochemistry/methods , Limit of Detection , Nanocomposites/chemistry , Nitriles/chemistry , Phenols/urine , Ruthenium/chemistry , Animals , Benzhydryl Compounds/chemistry , Chemistry Techniques, Synthetic , Electrochemistry/instrumentation , Electrodes , Endocrine Disruptors/chemistry , Endocrine Disruptors/urine , Humans , Metal Nanoparticles/chemistry , Models, Molecular , Molecular Conformation , Nanotechnology , Phenols/chemistry
8.
Ultrason Sonochem ; 48: 362-369, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30080561

ABSTRACT

A facile, green and one-pot synthesis strategy for the convenient preparation of well-dispersed gold nanoparticles (AuNPs) decorated reduced graphene oxide (RGO) without using any other toxic chemicals and reductants is reported herein. The synthesized AuNPs@RGO hybrid nanomaterials were characterized by UV-visible absorption spectroscopy, FT-IR, XRD, Raman, SEM, TEM and EDX analysis. The AuNPs@RGO acts as an efficient catalyst for the reduction of organic nitroaromatics (2- & 4-nitro phenols) in the presence of NaBH4. This newly synthesized hybrid AuNPs@RGO has superior catalytic activity over any other Au-nanomaterials ever reported. The rate of nitro aromatics reduction is found to be dependent on concentrations of substrate, reductant and catalyst. The mechanisms for the synthesis and catalytic reduction have been studied and discussed.

9.
Ultrason Sonochem ; 44: 196-203, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29680603

ABSTRACT

The novel N-CeO2 nanoparticles decorated on reduced graphene oxide (N-CeO2@rGO) composite has been synthesized by sonochemical method. The characterization of as prepared nanocomposite was intensely performed by UV-Vis, FT-IR, EDX, FE-SEM, HR-TEM, XRD, and TGA analysis. The synthesized nanomaterial was further investigated for its selective and sensitive sensing of paracetamol (PM) based on a N-CeO2@rGO modified glassy carbon electrode. A distinct and improved reversible redox peak of PM is obtained at N-CeO2@rGO nanocomposite compared to the electrodes modified with N-CeO2 and rGO. It displays a very good performance with a wide linear range of 0.05-0.600 µM, a very low detection limit of 0.0098 µM (S/N = 3), a high sensitivity of 268 µA µM-1 cm-2 and short response time (<3 s). Also, the fabricated sensor shows a good sensibleness for the detection of PM in various tablet samples.


Subject(s)
Acetaminophen/analysis , Electrochemical Techniques/methods , Graphite/chemistry , Lanthanum/chemistry , Nitrogen/chemistry , Ultrasonic Waves , Analgesics, Non-Narcotic/analysis , Antipyretics/analysis , Electrodes , Hydrogen-Ion Concentration , Limit of Detection , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Oxides/chemistry , Spectrometry, X-Ray Emission , Spectrophotometry, Ultraviolet , Spectroscopy, Fourier Transform Infrared , Thermogravimetry , X-Ray Diffraction
10.
Microb Pathog ; 114: 409-413, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29233780

ABSTRACT

A novel N-acyl substituted indole-linked benzimidazoles and naphthoimidazoles were synthesized. Their chemical structures were confirmed using spectroscopic tools including 1H NMR, 13C NMR and CHN-elemental analyses. Anti inflammatory activity for all target compounds was evaluated in-vitro. The synthesized compounds hinder the biofilm formation and control the growth of the pathogen, Staphylococcus epidermis. Anti microbial activity of the compounds was evaluated against both Gram negative and Gram positive bacteria such as Staphylococcus aureus (MTCC 2940), Pseudomonas aeruginosa (MTCC424), Escherchia coli (MTCC 443) and Enterococcus fecalis.


Subject(s)
Anti-Infective Agents/chemical synthesis , Anti-Infective Agents/pharmacology , Anti-Inflammatory Agents/chemical synthesis , Anti-Inflammatory Agents/pharmacology , Benzimidazoles/chemical synthesis , Benzimidazoles/pharmacology , Biofilms/drug effects , Indoles/chemical synthesis , Indoles/pharmacology , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Molecular Structure
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