Determination of catecholamines in pharmaceutical formulations using a biosensor modified with a crude extract of fungi laccase (Pleurotus ostreatus)

Journal of the Brazilian Chemical Society

Barbosa, Aneli de M.¹  Universidade Federal de São Carlos, São Carlos, Brazil¹  Leite, Oldair D.¹  Fatibello-Filho, Orlando¹  Universidade Estadual de Londrina, Londrina, Brazil¹ 

关键词: laccase;    Pleurotus ostreatus;    catecholamines;    biosensor;   

DOI  :  10.1590/S0103-50532003000200018

学科分类：化学（综合）

来源: SciELO

【 摘 要 】

A carbon paste biosensor modified with a crude enzymatic extract of the Pleurotus ostreatus fungi as a laccase source is proposed for catecholamine determination in pharmaceutical formulations. This enzyme catalyzes the oxidation of adrenaline or dopamine in the corresponding quinones and the current obtained in the electrochemical reduction of each of the products is related to the concentration of these catecholamines in the sample solution. The effect of the laccase concentration from 0.29 to 1.8 U/mg of carbon paste, pH from 3.0 to 8.0, scan rate from 10 to 40 mV s-1 and potential pulse amplitude from 10 to 60 mV on the differential pulse voltammetric response was investigated. The relative standard deviation was smaller than 1.8% for a 2.8 x 10-4 mol L-1 hydroquinone solution at pH 7.0 (n=10). Recoveries varied from 97.3 to 101% for adrenaline and from 95.8 to 102% for dopamine. The analytical curves were rectilinear in the adrenaline concentration range from 6.0 x 10-5 to 7.0 x 10-4 mol L-1 and 7.0 x 10-5 to 4.0 x 10-4 mol L-1 for dopamine, with detection limits of 7.9 x 10-6 mol L-1 and 9.8 x 10-6 mol L-1, respectively. This biosensor was used for adrenaline and dopamine determinations in pharmaceutical formulations. The results obtained using the proposed biosensor are in close agreement with those obtained using an American Pharmacopoeia procedure at a 95% confidence level.

【 授权许可】

Unknown