Resumen

PASSOS, Marieta L. C.; SARAIVA, M. Lúcia M. F. S.; LIMA, José L. F. C.  y  KORN, M. Graças A.. Determination of metoprolol, acebutolol and propranolol in pharmaceutical formulations using the same SIA system. J. Braz. Chem. Soc. [online]. 2008, vol.19, n.3, pp. 563-568. ISSN 0103-5053.  http://dx.doi.org/10.1590/S0103-50532008000300027.

A mechanized system for the determination of b-blockers in pharmaceutical formulations is presented. Using the Sequential Injection Analysis (SIA) technique it was achieved a simple, economical and versatile methodology adaptable to any pharmaceutical control involving these substances. It does not require any pre-treatment for the samples, as they must only be dissolved in acid before analysis. Linear calibration plots were obtained for metoprolol (40.52 - 250 mg L^-1), acebutolol (32.85 - 140 mg L^-1) and propranolol (16.58 - 120 mg L^-1). A R.S.D. lower than 5% was attained. The methodology was used in tablets, injections and prolonged-release capsules. Common excipients used in pharmaceuticals do not interfere. Statistical comparison of the results obtained with the proposed methodology and with the official methods showed good agreement (95% confidence level). SIA system produces only 2.50 mL of effluents per determination whereas the reference methodologies consume around 140 mL.

Palabras llave : beta-blockers; sequential injection analysis; SIA; spectrophotometry; pharmaceutical formulations.