A novel support for laccase immobilization: Cellulose acetate modified with ionic liquid and application in biosensor for methyldopa detection

作者：Moccelini Sally K; Franzoi Ana C^*; Vieira Iolanda C; Dupont Jairton; Scheeren Carla W

来源：Biosensors and Bioelectronics, 2011, 26(8): 3549-3554.

DOI：10.1016/j.bios.2011.01.043

• Cellulose acetate
• Ionic liquid
• Laccase
• Biosensor
• Methyldopa

A material based on cellulose acetate (CA) and the room temperature ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMI center dot N(Tf)(2)) was developed and characterized by scanning electron microscopy, electron dispersive spectroscopy and infrared analysis. Laccase (Lac) from Aspergillus oryzae was immobilized in this material to investigate the behavior of methyldopa by square-wave voltammetry. Under optimized conditions, the Lac biosensor based on CA/BMI center dot N(Tf)(2) exhibited an excellent electrocatalytic performance: the analytical curve showed good linear range for methyldopa concentrations from 34.8 to 370.3 mu M with a detection limit of 5.5 mu M. This sensor demonstrated acceptable stability (ca. 60 days; at least 350 determinations), good repeatability and reproducibility (relative standard deviations of 1.5 and 4.3%, respectively). The recovery study of methyldopa in pharmaceutical formulations ranged from 94.1 to 105.9%. The determination of this substance using the biosensor compared favorably with that using a spectrophotometry procedure at the 95% confidence level, and indicated potential application to methyldopa determination in pharmaceutical samples.

• 出版日期2011-4-15