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1.
Rapid Commun Mass Spectrom ; 37(21): e9626, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37799033

RESUMO

RATIONALE: Trimetazidine and its metabolites are prohibited substances in sports. With a growing number of adverse findings in human athletes, it is crucial to develop doping control strategies that include screening for trimetazidine in animal sports. This study aims to detect and characterize trimetazidine and its metabolites for doping control in camel racing. METHODS: Camel urine and plasma samples were collected from four healthy animals following a single oral dose of trimetazidine. In vitro investigations were conducted using camel liver samples. Liquid-liquid extraction and solid-phase extraction techniques were employed for the extraction of trimetazidine metabolites from plasma and urine matrices. The metabolites were analyzed using a Thermo Orbitrap Exploris LC-MS system with optimized settings to achieve maximum sensitivity and accurate mass measurements. RESULTS: Comprehensive metabolite profiling of trimetazidine in camels revealed the identification of seven phase I and five phase II metabolites. Phase I metabolites were primarily formed through dealkylation, while phase II metabolites were dominated by glucuronide conjugation of demethylated trimetazidine. The findings provided insights into the distinct metabolic pathways and biotransformation patterns of trimetazidine in camels under the experimental conditions. CONCLUSION: The developed method enables detection and characterization of trimetazidine and its metabolites in camels. The identified metabolites have the potential to serve as marker metabolites for trimetazidine abuse in camel racing. This study provides valuable insights into the metabolism of trimetazidine in camels.


Assuntos
Dopagem Esportivo , Trimetazidina , Animais , Humanos , Trimetazidina/urina , Camelus , Dopagem Esportivo/prevenção & controle , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , Detecção do Abuso de Substâncias/métodos
2.
J Nanosci Nanotechnol ; 19(5): 2522-2536, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30501749

RESUMO

Solid polymer blend electrolytes are widely studied due to their extensive applications particularly in electrochemical devices. Blending polymer electrolytes make thermal stability and higher mechanical strength and enhance the ionic conductivity while incorporate inorganic salt. In these studies, 50% polyvinyl alcohol (PVA), 50% poly(N-vinyl pyrrolidone) (PVP) and 10% ammonium bromide (NH4Br) doped with different molecular weight percentage (M.Wt.%) of cobalt sulfide nanoparticles (CoS-NPs) as nano filler is synthesized using solution casting technique. The various M.Wt.% of CoS-NPs mixed blend polymer films are characterized by various analytical methods such as FT-IR, XRD, TG-DSC, SEM and Impedance spectroscopy. FT-IR, XRD and TG-DSC analysis are revealed the structural and thermal stability of the complex formation between CoS-NPs and PVA/PVP/NH4Br polymer matrix. The ionic conductivity and the dielectric properties of PVA/PVP/NH4Br/doped CoS-NPs polymer blend electrolyte films are examined using impedance analysis. The antibacterial studies are showed higher activity for high conductivity polymer blend film. The highest ionic conductivity is found to be 5.42×10-4 S cm-1 for the M.Wt.% of composition 50%PVA:50%PVP:10%NH4Br:1.5%CoS-NPs with low activation energy 0.3373 eV at ambient temperature.

3.
J Nanosci Nanotechnol ; 18(6): 3944-3953, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442730

RESUMO

Biodegradable polymer blend electrolyte based on ammonium based salt in variation composition consisting of PVA:PVP were prepared by using solution casting technique. The obtained films have been analyzed by various technical methods like as XRD, FT-IR, TG-DSC, SEM analysis and impedance spectroscopy. The XRD and FT-IR analysis exposed the amorphous nature and structural properties of the complex formation between PVA/PVP/NH4Br. Impedance spectroscopy analysis revealed the ionic conductivity and the dielectric properties of PVA/PVP/NH4Br polymer blend electrolyte films. The maximum ionic conductivity was determined to be 6.14 × 10-5 Scm-1 for the composition of 50%PVA: 50%PVP: 10% NH4Br with low activation energy 0.3457 eV at room temperature. Solid state battery is fabricated using highest ionic conducting polymer blend as electrolyte with the configuration Zn/ZnSO4 · 7H2O (anode) ∥ 50%PVA: 50%PVP: 10% NH4Br ∥ Mn2O3 (cathode). The observed open circuit voltage is 1.2 V and its performance has been studied.

4.
Ultrason Sonochem ; 66: 104977, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32315841

RESUMO

The innovation of novel and proficient nanostructured materials for the precise level determination of pharmaceuticals in biological fluids is quite crucial to the researchers. With this in mind, we synthesized iron molybdate nanoplates (Fe2(MoO4)3; FeMo NPs) via simple ultrasonic-assisted technique (70 kHz with a power of 100 W). The FeMo NPs were used as the efficient electrocatalyst for electrochemical oxidation of first-generation antihistamine drug- Promethazine hydrochloride (PMH). The as-synthesized FeMo NPs were characterized and confirmed by various characterization techniques such as XRD, Raman, FT-IR, FE-SEM, EDX and Elemental mapping analysis and electron impedance spectroscopy (EIS). In addition, the electrochemical characteristic features of FeMo NPs were scrutinized by electrochemical techniques like cyclic voltammetry (CV) and differential pulse voltammetry technique (DPV). Interestingly, the developed FeMo NPs modified glassy carbon electrode (FeMo NPs/GCE) discloses higher peak current with lesser anodic potential on comparing to bare GCE including wider linear range (0.01-68.65 µM), lower detection limit (0.01 µM) and greater sensitivity (0.97 µAµM-1cm-2). Moreover, the as-synthesized FeMo NPs applied for selectivity, reproducibility, repeatability and storage ability to investigate the practical viability. In the presence of interfering species like cationic, anionic and biological samples, the oxidation peak current response doesn't cause any variation results disclose good selectivity towards the detection of PMH. Additionally, the practical feasibility of the FeMo NPs/GCE was tested by real samples like, commercial tablet (Phenergan 25 mg Tablets) and lake water samples which give satisfactory recovery results. All the above consequences made clear that the proposed sensor FeMo NPs/GCE exhibits excellent electrochemical behavior for electrochemical determination towards oxidation of antihistamine drug PMH.


Assuntos
Carbono/química , Eletroquímica/instrumentação , Antagonistas dos Receptores Histamínicos/análise , Ferro/química , Molibdênio/química , Nanoestruturas/química , Prometazina/análise , Sonicação , Técnicas de Química Sintética , Eletrodos , Vidro/química , Antagonistas dos Receptores Histamínicos/sangue , Antagonistas dos Receptores Histamínicos/urina , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Prometazina/sangue , Prometazina/urina , Temperatura
5.
J Nanosci Nanotechnol ; 19(11): 7026-7034, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31039855

RESUMO

The hydrothermally synthesized CuWO4 nanoparticles (NPs) were characterized with different analysis such as X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), High Resolution Transmission Electron Microscopy (HRTEM), Energy Dispersive X-ray Spectroscopy (EDX), Cyclic Voltammetry (CV), UV-Visible and Photoluminescence (PL) analysis. The prepared CuWO4 NPs were examined with Electrochemical Impedance Spectroscopy (EIS). SEM images show that CuWO4 NPs are highly spherical shaped morphology and porous in nature. The optical band gap of prepared CuWO4 NPs is found to be 2.12 eV. Photodegradation of diclofenac sodium (DFS) (medical waste) in the aqueous medium with CuWO4 NPs under visible light irradiation shows 98% degradation. The CuWO4 NPs was stable up to 5th cycle it can be used as a reusable photocatalyst for the DFS degradation. The electrical conductivity and dielectric properties of the CuWO4 NPs at room temperature is analyzed by EIS studies. The bulk conductivity value of the prepared nanoparticles is 1.477×10-5 S/cm at room temperature. The conductivity of CuWO4 NPs is found to be due to electrons movement. The CuWO4 NPs shows higher photocatalytic and electrocatalytic activity for decomposition of DFS and methanol electro-oxidation in alkaline medium respectively.

6.
Ultrason Sonochem ; 53: 44-54, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30559078

RESUMO

In this work, strontium cerate nanoparticles (SrCeO3 NPs, SC NPs) were developed through facile synthetic techniques (Ultrasound-Assisted (UA) and Stirring-Assisted (SA) synthesis) and utilized as an electrocatalyst for the selective and sensitive electrochemical detection of calcium channel blocker nifedipine (NDF). The as-prepared UASC NPs and SASC NPs were characterized using XRD, Raman, TEM, EDS, mapping, XPS and BET analysis which exposed the formation of SC NPs in the form of spherical in shape and well crystalline in nature. BET studies reveal that UASC NPs have maximum surface area than that of SASC NPs. Further, the use of the as-developed UASC NPs and SASC NPs as an electrocatalyst for the detection of NDF. Interestingly, the UASC NPs modified screen printed carbon electrode (UASC NPs/SPCE) exhibited an excellent electrocatalytic activity in terms of lower reduction potential and enhanced reduction peak current when compared to SASC NPs and unmodified SPCE. Moreover, as-prepared UASC NPs/SPCE displayed wide linear response range (LR, 0.02-174 µM), lower detection limit (LOD, 5 nM) and good sensitivity (1.31 µA µM-1 cm-2) than that of SASC NPs (LR = 0.02-157 µM, LOD = 6.4 nM, sensitivity - 1.27 µA µM-1cm-2). Furthermore, UASC NPs/SPCE showed an excellent selectivity even in the existence of potentially co-interfering compounds such as similar functional group containing drugs, pollutants, biological substances and some common cations/anions. The developed sensor was successfully employed for the determination of NDF in real lake water, commercial NDF tablet and urine samples with acceptable recovery.


Assuntos
Bloqueadores dos Canais de Cálcio/análise , Limite de Detecção , Nanopartículas/química , Nifedipino/análise , Óxidos/química , Óxidos/síntese química , Sonicação , Bloqueadores dos Canais de Cálcio/química , Catálise , Técnicas de Química Sintética , Eletroquímica , Eletrodos , Nifedipino/química
7.
Int J Biol Macromol ; 99: 223-232, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28237574

RESUMO

Cotton linters were dissolved in aq. (8% LiOH+15% urea) that was pre-cooled to -12.5°C. Using this solution cellulose gel films were prepared by regeneration method with ethyl alcohol as a coagulant. These wet films were diffused with 10wt% Cassia alata leaf extract that acted as a reducing agent. The leaf extract diffused cellulose wet films were used as the matrix. The wet matrix films were dipped individually in lower concentrated 1-5mM aq.AgNO3 source solutions in the presence of sunlight and allowed the solutions to react with the diffused leaf extract reducing agent which in situ generated the silver nanoparticles (AgNPs) inside the films as well as in the source solution. The AgNPs formed in the source solution were observed by transmission electron microscope (TEM) and scanning electron microscope (SEM) while those formed in situ the films were observed by SEM and the particle size distribution was determined. The cellulose/AgNP composite films showed good antibacterial activity against Escherichia coli bacteria. These nanocomposite films were also characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA) and tensile tests. At temperatures below 300°C, the thermal stability of the nanocomposite films was lower than that of the matrix due to the catalytic effect of AgNPs. The nanocomposite films also possessed good tensile properties. The ecofriendly cellulose/AgNP composite films with good antibacterial activity and tensile properties can be considered for medical applications like dressing materials.


Assuntos
Cassia/química , Celulose/química , Nanopartículas Metálicas/química , Nanocompostos/química , Extratos Vegetais/química , Folhas de Planta/química , Prata/química , Antibacterianos/química , Antibacterianos/farmacologia , Celulose/farmacologia , Nanotecnologia , Substâncias Redutoras/química , Temperatura , Resistência à Tração
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