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1.
Biosensors (Basel) ; 12(5)2022 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-35624610

RESUMO

This manuscript investigates the chemical and structural stability of 3D printing materials (3DPMs) frequently used in electrochemistry. Four 3D printing materials were studied: Clear photopolymer, Elastic photopolymer, PET filament, and PLA filament. Their stability, solubility, structural changes, flexibility, hardness, and color changes were investigated after exposure to selected organic solvents and supporting electrolytes. Furthermore, the available potential windows and behavior of redox probes in selected supporting electrolytes were investigated before and after the exposure of the 3D-printed objects to the electrolytes at various working electrodes. Possible electrochemically active interferences with an origin from the 3DPMs were also monitored to provide a comprehensive outline for the use of 3DPMs in electrochemical platform manufacturing.


Assuntos
Impressão Tridimensional , Eletroquímica , Eletrodos
2.
Anal Chim Acta ; 1077: 30-66, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31307723

RESUMO

This review summarizes progress in electroanalysis of organic compounds and biomacromolecules by means of bare BDD-based electrodes for the period of 2009-2018. New trends, which have emerged in the reported decade and which have improved their performance in batch voltammetric and amperometric methods and electrochemical detection in liquid flow techniques are commented. Importance of BDD surface termination, effect of boron doping level, and utilization of adsorption of analytes on BDD surfaces enabling development of adsorptive voltammetric techniques are addressed. Further, possibilities of simultaneous determination of analytes by means of voltammetric techniques utilizing computational approaches and multiple-pulse amperometric detection are discussed. Strategies leading to enhancement of sensitivity such as nanostructuring of the BDD surface, fabrication of BDD-based composite materials or new approaches in construction of microelectrodes and microelectrode arrays for biosensing represent another area of interest. Attention is paid to possibilities in detection of amino acids, peptides and proteins, nucleobases, nucleos(t)ides and DNA/RNA.


Assuntos
Boro/química , Diamante/química , Microeletrodos , Compostos Orgânicos/análise , DNA/análise , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Peptídeos/análise , Proteínas/análise , RNA/análise
3.
Talanta ; 178: 231-236, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29136816

RESUMO

We report the first amperometric method for the simultaneous determination of tert-butylhydroquinone (tBHQ), propyl gallate (PG), and butylated hydroxyanisole (BHA) using flow injection analysis coupled to multiple-pulse amperometry. A sequence of potential pulses was selected in order to detect tBHQ, PG, and BHA separately in a single injection step at a glassy carbon electrode without the need of a preliminary separation. A mixture of methanol and 0.040M Britton-Robinson buffer was used both as a carrier solution and for dilution of analyzed solutions before injection. The method is precise (RSD < 5%, n = 10), fast (a frequency of 140 injections h-1), provides sufficiently low quantification limits (2.51, 1.45, and 0.85µmolL-1 for tBHQ, PG, and BHA, respectively) and can be easily applied without high demands on instrumentation. As a practical application, the determination of these antioxidants contained in commercial chewing gum samples was carried out by applying a simple extraction procedure.


Assuntos
Hidroxianisol Butilado/análise , Eletroquímica/métodos , Análise de Injeção de Fluxo , Hidroquinonas/análise , Galato de Propila/análise , Goma de Mascar/análise , Eletroquímica/instrumentação , Eletrodos , Fatores de Tempo
4.
Talanta ; 85(5): 2594-8, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21962688

RESUMO

Methods for determination of 2-amino-4-nitrophenol and 4-amino-2-nitrophenol, metabolites of 2,4-dinitrophenol, were developed using differential pulse (DP) voltammetry and HPLC with amperometric and spectrophotometric detection. The applicability of these methods was tested by the determination of the analytes in model samples of urine after preliminary separation by solid-phase extraction. Voltammetry enabled parallel determination of both analytes, but its application in real matrix was severely limited due to the interference of other compounds present in urine. HPLC allowed the determination in real urine matrix down to micromolar concentrations; amperometric detection proved to be more sensitive and selective than the spectrophotometric one.


Assuntos
2,4-Dinitrofenol/metabolismo , Eletroquímica/métodos , 2,4-Dinitrofenol/análise , 2,4-Dinitrofenol/urina , Cromatografia Líquida de Alta Pressão , Extração em Fase Sólida
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