ABSTRACT
O desempenho de sensores fotoeletroquímicos, baseados no elétrodo Ti/TiO2 (sendo um exemplo de modelagem o sensor de hidrazina), foi descrito matematicamente e o respectivo modelo foi analisado por meio de teoria de estabilidade linear e análise de bifurcações. As condições do melhor desempenho destes sensores, bem como as de instabilidades oscilatória e monotônica, foram inferidas na base da análise do modelo.
The work of photoelectrochemical sensors, based on the Ti/TiO2 electrode (being an example for the modeling the hydrazine sensor), was described mathematically and the respective model was analyzed by means of linear stability theory and bifurcation analysis. The best response condition for this sensor, as also, the oscillatory and monotonic instabilities requirements, were inferred, basing on the model´s analysis.
ABSTRACT
The electrochemical behaviors of parathion(PT) on nano-Al2O3 film modified electrode(nano-Al2O3/GCE/CME) were investigated. It was found that the redox peak currents of PT remarkably increased and the oxidation peak potential negatively shifted at the nano-Al2O3/GCE/CME. All the experimental parameters were optimized and a simple and sensitive electroanalytical method was developed for the determination of PT. The oxidation peak current was linear with the concentration of PT over the range from 2.5×10-9 to 1.0×10-7 mol/L and 1.0×10-7 to 1.0×10-5 mol/L. A low detection limit of 1.0×10-9 mol/L was obtained for 30 s accumulation at open circuit(S/N=3). The relative standard deviation(n=10) was 3.8% for 1×10-5 mol/L PT. The proposed method was used for the quantitative analysis of PT in some vegetables and the results were satisfactory.
ABSTRACT
Objective To study the electrochemical features of an improved enzyme bioelectrode for biofuel cell. Methods The enzyme electrode was prepared via biotin-avidin technology and its electrochemical features were explored. The conditions such as layers of enzyme films, strength of glucose, scan speed and temperature, which affected the electrochemical behavior of enzyme electrode, were studied. Results The results showed that the electrode had good electric current response to glucose. The enzyme electrode prepared can fulfill the need of biofuel cell and is a promising electrode to be used in human body.