RESUMEN
Se ha estudiado la farmacocinética de la absorción gastrointestinal del busulfán en dos grupos deratas, tras su administración por vía oral. La dosis influye en el valor de la constante de absorción(Ka) y en la concentración máxima normalizada (Cmax), presentando ambos parámetros unadisminución al aumentar la dosis de 0,5 a 5 mg. El empleo de un modelo aparentemonocompartimental con absorción de primer orden permite una adecuada descripción del perfil deniveles plasmáticos del antineoplásico. El dimetilsulfóxido, utilizado como disolvente del busulfán, nointerfiere en los parámetros farmacocinéticos orales del mismo(AU)
We have studied the pharmacokinetics of gastrointestinal absorption of busulfan in two groups of rats,after oral administration. The dose effect on the value of the absorption constant (Ka) and thenormalized maximum concentration (Cmax), presenting both parameters decreased with increasingdose from 0.5 to 5 mg. Using a model with monocompartimental apparent first order absorptionallows an adequate description of the profile of plasma levels of antineoplastic. The dimethylsulfoxideused as busulfan solvent, does not interfere with oral pharmacokinetic parameters of it(AU)
Asunto(s)
Animales , Masculino , Femenino , Ratas , Busulfano/farmacocinética , Absorción Intestinal , Dimetilsulfóxido/farmacocinética , Dimetilsulfóxido/química , Antineoplásicos/farmacocinética , Cromatografía , Busulfano/farmacología , Dimetilsulfóxido/síntesis química , Dimetilsulfóxido/farmacología , 28599 , Análisis de VarianzaRESUMEN
This article deals with the simultaneous determination of dissolution profiles of two drugs with overlapped spectra, present in the same pharmaceutical formulation. The official procedure for the dissolution profile is adapted to the continuous-flow methodology; the dissolution vessel is connected to an FIA manifold, in which the sample aliquots from the dissolution vessel are treated in order to adjust to the suitable pH and dilution degree to be monitored. The resulting solution is injected into the carrier stream, an acetic acid-acetate buffer at pH 4.3 and forced to the flow-cell of the spectrophotometer. The simultaneous determination of both profiles is based on the first derivative spectra and the zero-crossing mathematical procedure. The empirical profile of the curve is adjusted by regression using different approaches; the three-parameter plot method is selected. The analytical errors, when the concentration of one drug is very low or very high, are also checked. A binary mixture in commercially available formulations of solid oral administration of sulphametoxazole and trimethoprim is presented.