Simultaneous determination of digoxin and digitoxin by micellar electrokinetic chromatography and application to drug formulations

Abstract

A simple micellar electrokinetic chromatographic method is described for simultaneous determination of digoxin and digitoxin. The simultaneous analysis of digoxin and digitoxin was performed in Tris buffer (10 mM; pH 9) with 90 mM sodium dodecyl sulfate and 10% isopropyl alcohol as an anionic surfactant and organic modifier. Under these conditions, good separation with high efficiency is achieved in short analysis times. Several parameters affecting the separation of the drugs were studied, including the pH and concentrations of the Tris buffer and sodium dodecyl sulfate. The linear range of the method for the determination of digoxin and digitoxin was over 0.01 -0.3 mg/mL; the detection limit (signal to noise ratio = 3; injection 3.5 kPa 3 s) was 4 and 6 lg/mL, respectively. Application of the proposed method to the determination of digoxin in commercial tablets and in injections proved to be feasible.

Concentrações de oleandrina nas folhas de Nerium oleander de diferentes cores da floração

“…Diversas metodologias analíticas foram desenvolvidas para a determinação das concentrações de cardenolídeos, incluindo cromatografia em camada delgada (CCD) (KARAWYA et al, 1973), cromatografia planar (TURKMEN et al, 2013), espectrofotometria (SOLICH et al, 1992), cromatografia capilar eletrocinética micelar (TSENG et al, 2003), HPLC com derivatização para detecção por fluorescência (BELSNER & BÜCHELE, 1996), HPLC com detector amperométrico (KELLY et al, 1995), radioimunensaio após separação por HPLC (PLUM & DALDRUP, 1986) e cromatografia líquida acoplada à espectrometria de massas (NEWMAN et al, 2001). A metodologia empregada de preparo da amostra por separação em fase sólida para posterior determinação por HPLC-UV se mostrou bastante eficaz e sensível, podendo ser empregada em trabalhos futuros.…”