Electro-Catalytic Resolution and Simultaneous Determination of Two Phenolic Antioxidants

Natural phenolic antioxidants are one of the widely studied compounds in life sciences due to their important role in oxidative stress prevention and repair. The structural similarity of these antioxidants and their simultaneous presence in the plant samples stipulate the development of methods for their quantification. The current work deals with the simultaneous determination of vanillin and its bioprecursor ferulic acid using a voltammetric sensor for the first time. A sensor based on the layer-by-layer deposition of the polyaminobenzene sulfonic acid functionalized single-walled carbon nanotubes (f-SWCNTs) and electropolymerized bromocresol purple has been developed for this purpose. The best response of co-existing target analytes was registered for the polymer obtained from the 25 µM dye by 10-fold potential cycling from 0.0 to 1.2 V with the scan rate of 100 mV s−1 in 0.1 M phosphate buffer (PB), pH 7.0. Scanning electron microscopy (SEM), cyclic voltammetry and electrochemical impedance spectroscopy (EIS) confirmed the effectivity of the sensor developed. The linear dynamic ranges of 0.10–5.0 µM and 5.0–25 µM for both analytes with the detection limits of 72 nM and 64 nM for ferulic acid and vanillin, respectively, were achieved in differential pulse mode. The sensor was applied for the analysis of vanilla extracts.

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Direct and simultaneous determination of four phenolic antioxidants in biodiesel using differential pulse voltammetry assisted by artificial neural networks and variable selection by decision trees

Fuel ◽

10.1016/j.fuel.2018.09.048 ◽

2019 ◽

Vol 236 ◽

pp. 803-810 ◽

Cited By ~ 11

Author(s):

Lívia de Souza Schaumlöffel ◽

Jônathan William Vergani Dambros ◽

Pedro Rafael Bolognese Fernandes ◽

Mariliz Gutterres ◽

Clarisse Maria Sartori Piatnicki

Keyword(s):

Neural Networks ◽

Artificial Neural Networks ◽

Variable Selection ◽

Differential Pulse Voltammetry ◽

Decision Trees ◽

Simultaneous Determination ◽

Differential Pulse ◽

Phenolic Antioxidants ◽

Pulse Voltammetry

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A general computer program for the extended plate overlap algorithm

International Astronomical Union Colloquium ◽

10.1017/s0252921100074236 ◽

1978 ◽

Vol 48 ◽

pp. 287-293 ◽

Cited By ~ 1

Author(s):

Chr. de Vegt ◽

E. Ebner ◽

K. von der Heide

Keyword(s):

Computer Program ◽

Simultaneous Determination ◽

General Computer Program ◽

General Computer

In contrast to the adjustment of single plates a block adjustment is a simultaneous determination of all unknowns associated with many overlapping plates (star positions and plate constants etc. ) by one large adjustment. This plate overlap technique was introduced by Eichhorn and reviewed by Googe et. al. The author now has developed a set of computer programmes which allows the adjustment of any set of contemporaneous overlapping plates. There is in principle no limit for the number of plates, the number of stars, the number of individual plate constants for each plate, and for the overlapping factor.

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