An amperometric biosensor for trans-resveratrol determination in aqueous solutions by means of carbon paste electrodes modified with peroxidase basic isoenzymes from Brassica napus

作者：Granero Adrian Marcelo; Fernandez Hector; Agostini Elizabeth; Zon Maria Alicia^*

来源：Electroanalysis, 2008, 20(8): 858-864.

DOI：10.1002/elan.200704109

• t-resveratrol
• amperometric biosensors
• peroxidase basic isoenzymes
• Brassica napus
• enzymatic kinetic parameters

The catalytic properties of peroxidase basic isoenzymes (PBI's) from Brassica napus towards trans-resveratrol (t-Res) oxidation were demonstrated by the first time by conventional UV-visible spectroscopic measurements. The enzymatic reaction rate was studied under different experimental conditions and the kinetics parameters were determined. An amperometric biosensor based on Brassica napus PBI's to determine t-Res is also proposed by the first time. The method employs a dialysis membrane covered, PBI's entrapped and ferrocene (Fc)-embedded carbon paste electrode (PBI's-Fc-CP) and is based on the fact that the decreased amount of H2O2 produced by the action of PBI's is proportional to the oxidised amount of t-Res in the solution. Comparative amperometric experiments showed that, in spite of PBI's activity was much lower than commercial horseradish peroxidase (HRP) activity, t-Res was a much better substrate for PBI's biosensors than those biosensors constructed by using HRP. The PBI's-Fe-CP biosensors showed a very good stability during at least twenty days. The reproducibility and the repeatability were 4.5% and 8.3%, respectively, showing a good biosensor performance. The calibration curve was linear in the t-Res concentration (Ct-Res) range from 1 x 10(-6) to 2.5 x 10(-5) M, with a sensibility of (2.31 +/- 0.05) x 10(6) nA M-1. The lowest Ct-Res value measured experimentally for a signal to noise ratio of 3:1 was 0.83 mu M.

• 出版日期2008-4