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1.
Sci Rep ; 14(1): 21972, 2024 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-39304680

RESUMO

The recent investigation targets to use adapted carbon paste (CP) with copper nanoparticles (CuNs) operating in a phosphate buffer (PBS) medium with a pH range of 5.0-8.0, to synthesize a novel, susceptible, and simple electrochemical sensor for the detection of one of the most important drugs, vitamin B6. Copper (Cu) is one of the most three common essential trace elements found in the bodies of both humans and animals, along with iron and zinc for all crucial physiological and biochemical functions. Its properties, which are assessed using a variety of methods including scanning electron microscopy (SEM), cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS), have also drawn a lot of attention recently. We considered the effects of pH, buffer, scan rate, interference, and calibration curve. The susceptible electrode's linear calibration curve encompassed concentration values between 8.88 and 1000.0 µM. The calculated limits of detection and quantification were 32.12 and 107.0 µM, respectively. Furthermore, this method was established in real human urine samples and drug validation which have been shown satisfactory results for vitamin B6 detection.


Assuntos
Carbono , Cobre , Técnicas Eletroquímicas , Eletrodos , Vitamina B 6 , Carbono/química , Humanos , Técnicas Eletroquímicas/métodos , Vitamina B 6/análise , Vitamina B 6/urina , Cobre/análise , Cobre/urina , Piridoxina/análise , Piridoxina/urina , Nanopartículas Metálicas/química , Concentração de Íons de Hidrogênio , Limite de Detecção , Espectroscopia Dielétrica/métodos
2.
Int J Biol Macromol ; 277(Pt 1): 134178, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39067726

RESUMO

Pepsin as an aspartic acid protease member and one of the three foremost proteolytic enzymes in the digestive system is essential to be detected. An electrochemically polymerized tyrosine film on carbon paste electrode (pTyr/CPE) has been synthesized by electro-polymerization donating an affordable electrochemical sensor to sense salivary pepsin as a diagnostic technique for gastroesophageal reflux disease (GRD) due to saliva collection is non-invasive and relatively comfortable. The pTyr/CPE was applied for Voltammetric sensing of pepsin and its quantification in phosphate buffer solution of pH 2.0 (PBS). Scanning electron microscopy (SEM) was conducted to learn the surface morphology. Cyclic voltammetry (CV), differential pulse voltammetry (DPVs), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) were developed to realize the electrocatalytic activity of the sensor. The pTyr/CPE proceeded as a sensitive detector to pepsin with two linear ranges from 1 to 20 & 20 to 100 ng/mL donating two limits of detection as 0.5 & 0.09 ng/mL, respectively, and high selectivity toward pepsin, as well as stability and fast response of 1.5 s. Consequently, it is guessed that the pTyr/CPE sensor could be supportive for the initial diagnosis of GRD through the detection of pepsin in saliva. Finally, we quantified the pepsin levels in saliva samples of LPR patients (n = 2), showing that the results were agreeable with those from the electrochemical sensor.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Pepsina A , Saliva , Pepsina A/análise , Saliva/química , Humanos , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Eletrodos , Tirosina/análise , Espectroscopia Dielétrica , Refluxo Gastroesofágico/diagnóstico , Limite de Detecção
3.
Mater Sci Eng C Mater Biol Appl ; 103: 109780, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349436

RESUMO

Graphene oxide nanoparticles/polythreonine polymer as a nano-coating on AZ91E Mg alloy was considered as a new temporary implant for gastrectomy applications. This coating as a novel one is decomposable and has bio-viability possessions. Various electrochemical measurements were utilized for corrosion performance estimation of Mg alloy in peritoneal fluid with time of dipping. It was recognized that the nano-coating is fixed for 20 days giving unexpected high corrosion resistance. All experimental outcomes were verified by scanning electron microscope (SEM) and Energy dispersive X-ray (EDX) techniques. Moreover, in vitro antibacterial, and cytotoxicity of metal with and/or without coating utilizing MTT assay for cell viability analysis were achieved.


Assuntos
Ligas/química , Materiais Revestidos Biocompatíveis/química , Gastrectomia , Grafite/química , Magnésio/química , Teste de Materiais , Suturas , Linhagem Celular , Corrosão , Humanos , Propriedades de Superfície
4.
J Mater Chem B ; 4(26): 4542-4548, 2016 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32263397

RESUMO

A novel system of electrodeposited gold nanoparticles on a carbon paste electrode was utilized as an electrochemical sensor to monitor the corrosion performance of 316L stainless steel alloy in aqueous humor containing moxifloxacin hydrochloride (MFH) drug. Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and potentiodynamic polarization measurements were used to estimate the corrosion performance of 316L stainless steel alloy in aqueous humor with immersion time. The experimental data was confirmed by scanning electron microscopy (SEM), Energy dispersive X-ray analysis (EDX) and antibacterial activity. All techniques conform well to each other and confirmed that the tested alloy corrosion decreases with increasing immersion time in aqueous humor. Corrosion is more inhibited after the addition of MFH drug. In addition, as the concentration of the drug increases, the protection efficiency of the tested alloy increases. This behavior was confirmed by sensing the drug concentration with time using the modified carbon paste electrode.

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