Electrochemical Behavior and Determination of Fluconazole

Abstract

O comportamento eletroquímico do fluconazol demonstrou oxidação irreversível com mecanismos eletroquímicos-químicos dependentes do material eletródico. Em eletrodos de Pt observou-se adsorção do reagente sob a aplicação de potenciais positivos, enquanto adsorção preferencial dos produtos foi observada em eletrodo de carbono vítreo. Em valores de pH inferiores a 7,0, a corrente do processo anódico é intensamente diminuída. Em eletrodo de pasta de carbono e tampão fosfato, pH 8,0, a corrente de oxidação variou linearmente com a concentração de fluconazol em solução, Ipa = 5,7×10 -5 (mA) × 0,052 [Fluconazol] (µg mL -1 ), no intervalo de 48,0 a 250,0 µg mL -1 . O limite de detecção obtido foi 6,3 µg mL -1 .The electrochemical behavior of fluconazole showed an irreversible oxidation process, with the electrochemical -chemical mechanism being highly dependent on the electrode material. Adsorption of reagent at positive applied potential was observed at Pt electrode while preferential adsorption of the oxidation products was observed at Glassy Carbon surfaces. In pH below 7.0, the anodic current process was intensively decreased. At carbon paste electrode, the fluconazole oxidation current, recorded in phosphate buffer solution (pH 8.0), changed linearly with the fluconazole concentration, Ipa = 5.7×10 -5 (mA) × 0.052 [Fluconazol] (µg mL -1 ), in the range of 48.0 to 250.0 µg mL -1. The detection limit obtained was 6.3 µg mL -1 .

Spectrophotometric methods based on charge transfer complexation reaction for the determination of some antifungal drugs in pure and dosage forms

“…The literature survey revealed that a few analytical methods have been reported for the determination of the studied drugs in pure drug, pharmaceutical dosage forms and biological samples using liquid chromatography either in single or in combined forms [3][4][5], electrochemical methods [6,7], spectroflourimetric methods [3,8] and spectrophotometric methods [9][10][11][12][13][14]. Visible spectrophotometry, because of simplicity and cost effectiveness, sensitivity and selectivity, fair accuracy, precision and available in most quality control laboratories, have remained competitive in an area of chromatography techniques for pharmaceutical analysis.…”

“…Charge transfer complexes of some antifungal drugs fluconazole (FLU), sertaconazole nitrate (SER) and miconazole nitrate (MCO) as electron donor with the σ-acceptor iodine (I2) and 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ), p-chloranilic acid (p-CLA) and 7,7,8, as π-acceptors in acetonitrile were investigated. The formation of the colored charge-transfer complexes were utilized in the development of simple, rapid and accurate spectrophotometric methods for the analysis of the cited drugs in pure forms and pharmaceutical formulations at 365 nm for MCO and SER using I2 method, at 460 nm for FLU and SER using DDQ method, at 535 and 530 nm for FLU and SER, respectively, using p-CLA method and at 842 nm for MCO and SER using TCNQ method.…”