FLOW INJECTION SPECTROFLUORIMETRIC DETERMINATION OF CARVEDILOL MEDIATED BY MICELLES

SILVA, RAUL A.; WANG, CHIEN CHUN; FERNANDEZ, LILIANA PATRICIA; MASI, ADRIANA NOEMI

TALANTA

Elsevier

Año: 2008 vol. 76 p. 166 - 171

0039-9140

A novel FI-spectrofluorimetric methodology for the determination of carvedilol in microheterogeneous medium has been developed. In the sodium dodecyl sulfate (SDS) surfactant medium, the electrolyte NaCl leads to an additional fluorescent enhancement. A total enhancement of 3.1 fold in the native fluorescent response was achieved respect to aqueous medium. Using lexc = 286 nm and lem = 341 nm, a good linear relationship was obtained in the range of 9 10-8 to 1.10-6 mol · L-1 with a detection limit of 3.63 10-9 mol · L-1 (S/N=3). This method was also applied to determine carvedilol in commercial pharmaceutical formulations. Good concordance was found between the nominal (6.25 mg, 12.5 mg y 25.0 mg) and experimental values. The new methodology developed showed high selectivity respect to the common excipients used in pharmaceuticals. From the fluorescence properties, binding constants for carvedilol-SDS was determined being 3.2 102  L.mol-1.