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Azul de cresil brilhante (BCB) foi eletropolimerizado sobre a superfície de um eletrodo de carbono líquido iônico (CILE) por voltametria cíclica de varredura na faixa de potencial de-0,5 a 1,0 V. CILE foi preparado usando o 1-etil-3-metil-imidazólio tetrafluoroborato ([EMIM]BF 4) como modificador. Um filme polimerico estável de BCB foi obtido no CILE com aparecimento de um par de picos redox. As características do filme PBCB foram estudadas por diversos métodos tais como, microscopia eletrônica de varredura (SEM), espectroscopia de impedância eletroquímica (EIS) e voltametria cíclica. O eletrodo modificado apresentou excelente resposta eletrocatalítica para ácido ascórbico com o aumento das respostas eletroquímicas. Sob condições ótimas, uma boa resposta voltamétrica linear foi obtida no intervalo 2,0 × 10-5-3,0 × 10-3 mol L-1 , com limite de detecção de 6,5 μmol L-1 (3s). Brilliant cresyl blue (BCB) was electropolymerized on the surface of a carbon ionic liquid electrode (CILE) by cyclic voltammetric sweep in the potential range from-0.5 to 1.0 V. CILE was prepared by using 1-ethyl-3-methyl-imidazolium tetrafluoroborate ([EMIM]BF 4) as modifier. The stable polymer film of BCB was obtained on the CILE and a pair of redox peaks appeared. The characteristics of PBCB film was studied by different methods such as scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry. This modified electrode showed excellent electrocatalytic response to ascorbic acid with the increase of the electrochemical responses. Under the optimal conditions a good linear voltammetric response could be obtained over the range of 2.0×10-5-3.0×10-3 mol L-1 and the detection limit was got as 6.5 μmol L-1 (3s).

In this paper a new electrochemical method based on the ionic liquid modified carbon paste electrode (IL-CPE) was proposed for the determination of adenosine-5¢-triphosphate (ATP) in a pH 4.5 Britton-Robinson (B-R) buffer solution. IL-CPE was prepared by using 1-butyl-3-methylimidazolium trifluoroacetate (BMIMCF 3 COO) as the modifier. Cyclic voltammetry was used to investigate the electrochemical behaviors of ATP on the IL-CPE, and the results indicated that IL-CPE exhibited strong electrocatalytic ability to promote the oxidation of ATP with a single well-defined irreversible adsorption-controlled oxidation peak appeared. The electrochemical reaction parameters of ATP were calculated with the results of the electron transfer coefficient (a) as 0.40, the electron transfer number (n) as 1.17, the apparent heterogeneous electron transfer rate constant (ks) as 3.66 × 10 -6 s -1 and the surface coverage (G T ) as 2.48 × 10 -9 mol cm -2 . Under the selected conditions the proposed IL-CPE showed good performances to the ATP detection in the concentration range from 0.1 to 1000.0 mmol L -1 with the detection limit as 3.65 × 10 -8 mol L -1 (3s) by differential pulse voltammetry. The method showed good selectivity to the ATP detection without the interferences of coexisting substances and was successfully applied to the ATP injection samples detection with satisfactory results.