The Theoretical Description for a Sucralose Electrochemical Cathodical Determination over a 9-9´-Diacridyl-modified Electrode

A novel electroanalytical process for sucralose determination has been theoretically suggested. Sucralose is immobilized over an acridine derivative 9-9´-diacridyl, yielding a quaternary salt, which is thereby gradually electrochemically reduced to an N-N´-disubstituted acridone derivative. The correspondent mathematical model has been developed and analyzed by means of linear stability theory and bifurcation analysis, and this analysis has shown the high probability of the oscillatory and monotonic instabilities, due to the double electric layer structure changes during all of the stages of the process. Nevertheless, it also confirms the efficiency of 9-9´-diacridyl-modified electrode for sucralose determination in an electroanalytical system, which may be coupled with a fluorescent indicator. DOI:  http://dx.doi.org/10.17807/orbital.v13i3.158

The Theoretical Description for Chlorantraniliprole Electrochemical Determination, Assisted by Squaraine Dye – Nano-CuS Composite

The theoretical description for the chlorantraniliprole electrochemical determination, assisted by the hybrid composite of squaraine dye with CuS nanoparticles has been described. The correspondent reaction mechanism has been proposed, and the correspondent mathematical model has been developed and analyzed by means of linear stability theory and bifurcation analysis. It has been shown that the chlorantraniprole electrochemical anodical determination on high potential may be efficiently provided by cupper sulfide nanoparticles, stabilized by the squaraine dye. On the other hand, the oscillatory and monotonic instability is also possible, being caused by DEL influences of the electrochemical stage. DOI: http://dx.doi.org/10.17807/orbital.v13i3.151

THE THEORETICAL DESCRIPTION FOR 4-NITROQUINOLINE-N-OXIDE ELECTROCHEMICAL DETERMINATION ON V(OH)2-MODIFIED ELECTRODE

In this work, the possibility of use of vanadium (II) dioxide as an electrode modifier for the cancer marker 4-nitroquinoline-N-oxide has been made. Two parallel mechanisms of assisted electroanalytical determination are possible, due to the presence of peroxide group and nitric group. Both of them provide the electrode reversibility, due to the formation of V(IV) and V(III) compounds. In both of the cases, the electroanalytical process is efficient. On the other hand, the oscillatory behavior probability in this system is correspondent to the electroanalytical process with sequent or parallel electrochemical stages

A descrição matemática do desempenho do novo derivado acridínico na detecção eletroanalítica do conteúdo total do ácido gálico em alfarroba

The possibility of the use of the novel acridinic derivative, containing an electron donor moiety in the total gallic acid content determination in carob gum has been evaluated by means of a theoretical analysis. The correspondent mathematical model has been analyzed by linear stability theory and bifurcation analysis. It was shown that the phosphazoic acridine derivative may serve as an efficient electrode modifier for electroanalytical determination of the total content of gallic acid in carob. The causes for the oscillatory and monotonic behavior have also been stipulated.A possibilidade do uso de um novo derivado de acridina, munido de um grupo doador de elétrons, como modificador de elétrons para a detecção do conteúdo total do ácido gálico em goma de alfarroba tem sido avaliada mediante uma análise teórica. O modelo matemático correspondente foi analisado mediante a teoria de estabilidade linear e análise de bifurcações. Foi mostrado que o derivado fosfazoico da acridina pode servir de modificador eficiente para a detecção eletroanalítica do conteúdo total do ácido gálico em alfarroba. As causas dos comportamentos oscilatório e monotônico também foram detectadas

The Theoretical Description for the Perylaldehyde Aldoxime Electrochemical Determination, Assisted by the Novel Squaraine Dye – VO(OH) - Composite

For the first time, the perillaldehyde aldoxime electrochemical determination has been evaluated from the theoretical point of view. The correspondent mathematical model, including different scenarios of the electroanalytical process, has been developed and analyzed by means of linear stability theory and bifurcation analysis. The model analysis clearly shows that the composite of a squaraine dye in organic phase and vanadium oxyhydroxide in the inorganic phase may be an efficient electrode modifier for perillaldehyde aldoxime electrochemical determination. On the other hand, both oscillatory and monotonic instabilities may be realized in the electroanalytical process, and their probability will strongly depend on the direction of the electroanalytical scenario in the concrete conditions. DOI: http://dx.doi.org/10.17807/orbital.v12i3.1498</p

The Theoretical Description for Magnesium Chlorate Electrochemical Determination on a Magnezone-XC Modified Electrode

An interesting electroanalytical process for magnesium chlorate electrochemical determination has been described theoretically. The process involves the complex formation of magnesium cation with the azo dye Magnezone XC and the electropolymerization of the resulting complex compound in the presence of the chlorate-ion by two parallel mechanisms. The correspondent mathematical model has been developed and analyzed by means of linear stability theory and bifurcation analysis. It has been shown that from both electroanalytical and electrosynthetical points of view the system is efficient. The linear dependence between the electrochemical parameter and salt concentration is obtained easily, and the material formed during the electroanalytical process is highly conductive and catalytic. On the other hand, the oscillatory behavior in this system will be caused by double electric layer influences on both complexation and electropolymerization stages. DOI: http://dx.doi.org/10.17807/orbital.v12i4.1534</p

THE THEORETICAL DESCRIPTION OF PRODIGIOSIN ALKALOIDS ELECTROCHEMICAL DETERMINATION ON TRIAZOLIC DERIVATIVES, REINFORCED BY COBALT AND NICKEL OXYHYDROXIDES

The theoretical description of prodigiosin pigment electrochemical determination, assisted by novel triazolic derivatives, reinforced by cobalt and nickel oxyhydroxides, has been described. It was noticed that both cobalt and nickel oxyhydroxides may serve as efficient electrode modifiers of prodigiosin electrochemical determination in neutral and lightly alkaline media. The electroanalytical process is diffusion-controlled. The oscillatory and monotonic instabilities in the system are possible, being caused by DEL influences on the chemical and electrochemical stages

The Theoretical Description for Fluoxetine Electrochemical Determination, Assisted by CoO(OH)-Nanoparticles, Deposited Over the Squaraine Dye

The theoretical description of the fluoxetine electrochemical determination over a CoO(OH) – Squaraine Dye composite has been carried out in this work. The correspondent mathematical model has been developed and analyzed by means of the linear stability theory and bifurcation analysis. It has been shown that the cobalt(III) oxyhydroxide, stabilized by squaraine dye layer, may be efficient electrode modifier for fluoxetine electrochemical determination. The possibility for the oscillatory and monotonic instabilities has also been verified. DOI: http://dx.doi.org/10.17807/orbital.v13i1.1573</p