Cinética de descomposición de penicilinas sintéticas

Abstract

Se ha realizado un estudio de la estabilidad de la oxacilina sódica en medio acuoso usando técnicas espectrofotométricas. El máximo de absorción que presenta la forma mercaptada de la oxacilina aparece a la longitud de onda de 344 nm. Se ha comprobado el cumplimiento de la ley de Lamber-Beer entre las concentraciones de 1'13·10-5 M y 1'36·10-4 M (E344 = 4859'62 mol-1 · 1cm-1). Esta penicilina se descompone siguiendo una cinética de degradación de orden uno. A temperaturas más elevadas se aumenta su velocidad de degradación. Se ha comprobado que es más estable en pH próximos a la neutralidad y en medios hidroalcohólicos (etanol y propanol) siendo más estable cuanto mayor es la concentración de alcohol en el medio.

A study of the stability of sodium oxaciline in water means by using spectrophotometries techniques has been done. The maximun of absorcion that present the mercapt form of oxaciline appears at wave lenght of 344 nm. The fulfilment of the Lamber-Beer law has been proved between the concentrations of A study of the stability of sodium oxaciline in water means by using spectrophotometries techniques has been done. The maximun of absorcion that present the mercapt form of oxaciline appears at wave lenght of 344 nm. The fulfilment of the Lamber-Beer law has been proved between the concentrations of l' 13·1O-5M Y 1 '36·1O-4M (E 344 = 4859'62 mol-I·1· cm-l). This peniciline is broken down following a cinetic of degradation of rate one. At higher temperature its degradation speed is increased. It has been proved that it is more stable in pH nearer to neutrality and in hidroalcoholic (etyl alcohol and propyl alcohol) means, being more stable the highest is the concentration of alcohol in the means.. This peniciline is broken down following a cinetic of degradation of rate one. At higher temperature its degradation speed is increased. It has been proved that it is more stable in pH nearer to neutrality and in hidroalcoholic (etyl alcohol and propyl alcohol) means, being more stable the highest is the concentration of alcohol in the means.