Premium
Fast determination of ethambutol in pharmaceutical formulations using capillary electrophoresis with capacitively coupled contactless conductivity detection
Author(s) -
da Silva José Alberto Fracassi,
de Castro Nathan Vitorazzi,
de Jesus Dosil Pereira,
Faria Adriana F.,
De Souza Marcus V. N.,
de Oliveira Marcone Augusto Leal
Publication year - 2010
Publication title -
electrophoresis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.666
H-Index - 158
eISSN - 1522-2683
pISSN - 0173-0835
DOI - 10.1002/elps.200900404
Subject(s) - chromatography , capillary electrophoresis , chemistry , resolution (logic) , detection limit , ethambutol , analytical chemistry (journal) , conductivity , biochemistry , streptomycin , artificial intelligence , computer science , antibiotics
A method for the determination of ethambutol (EMB), a first‐line drug against tuberculosis, based on CE with capacitively coupled contactless conductivity detection is proposed. The separation of EMB and its main product of degradation were achieved in less than 3 min with a resolution of 2.0 using a BGE composed of 50 mmol/L histidine and 30 mmol/L MES, pH 6.30. By raising the pH to 8.03, the analysis time was reduced to 1.0 min, but with a significant loss of resolution (0.7). Using the best separation conditions, linearity of 0.9976 ( R 2 , five data points), sensitivity of 1.26×10 −4 V min μmol −1 L, and LOD and quantification of 23.5 and 78.3 μmol/L, respectively, were obtained. Recoveries at four levels of concentration ranged from 95 to 102% and the concentration range studied ranged from 100 to 500 μmol/L. The results obtained for the determination of EMB in pharmaceutical formulations were compared with those obtained by using CE with photometric detection.