A very important factor in the stability study of a drug is the knowledge of its photo-sensibility and this needs a careful management in the design of pharmaceutical formulation and packaging (1). The aim of this work is the study of the photochemical degradation of amiloride and a complete description of its kinetic pathway. A novel chemometric method, hybrid hard- and soft- multivariate curve resolution (H/S-MCR) (2) has been applied on UV spectral data from the drug exposed under various stressed experimental conditions. The experiments were varied as medium (ethanol and water) and as pH values (3, 7, 9 and 12). MCR analysis of the collected spectral data was demonstrated able to explain the mechanism of the degradation process and to resolve the kinetic profiles. The spectra of the pure photoproducts and evaluation of the rate constants were also calculated (3). The defined kinetic model was described with four consecutive first-order reactions (A>B>C>D>E). Degradation in ethanol was observed slower than in water whereas higher pH value showed an increase of the rate constants. (1) G. Ragno, A. Risoli, G. Ioele, E. Cione, M. De Luca, J. Nanosc. Nanotech. 2006, 6, 2979-2985 (2) A.de Juan, R.Tauler, Crit. Rev. Anal. Chem. 2006, 36, 163-176. (3) S. Mas, A. de Juan, S. Lacorte, R. Tauler, Anal. Chim. Acta, 2008, 618, 18-28
Photodegradation profile of amiloride by multivariate curve resolution applied on spectroscopic data
DE LUCA M;IOELE, Giuseppina;RAGNO, Gaetano;
2009-01-01
Abstract
A very important factor in the stability study of a drug is the knowledge of its photo-sensibility and this needs a careful management in the design of pharmaceutical formulation and packaging (1). The aim of this work is the study of the photochemical degradation of amiloride and a complete description of its kinetic pathway. A novel chemometric method, hybrid hard- and soft- multivariate curve resolution (H/S-MCR) (2) has been applied on UV spectral data from the drug exposed under various stressed experimental conditions. The experiments were varied as medium (ethanol and water) and as pH values (3, 7, 9 and 12). MCR analysis of the collected spectral data was demonstrated able to explain the mechanism of the degradation process and to resolve the kinetic profiles. The spectra of the pure photoproducts and evaluation of the rate constants were also calculated (3). The defined kinetic model was described with four consecutive first-order reactions (A>B>C>D>E). Degradation in ethanol was observed slower than in water whereas higher pH value showed an increase of the rate constants. (1) G. Ragno, A. Risoli, G. Ioele, E. Cione, M. De Luca, J. Nanosc. Nanotech. 2006, 6, 2979-2985 (2) A.de Juan, R.Tauler, Crit. Rev. Anal. Chem. 2006, 36, 163-176. (3) S. Mas, A. de Juan, S. Lacorte, R. Tauler, Anal. Chim. Acta, 2008, 618, 18-28I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
