Julkunen R J
Med Biol. 1977 Feb;55(1):41-7.
The diffusion of three weakly acidic drugs (warfarin, sulfaethidole, and barbital) in cyclohexane-buffer and n-octanol-buffer systems was studied by two different methods; shaking and model cell type of experimentation. At low pH values the drugs moved generally more readily into the organic phases than at higher pH. Moreover, when the shaking method was used the drugs moved readily to the n-octanol phase even at higher pH levels. Lecithin improved the diffusion at low more than at high pH levels. Thus, the results varied according to the organic phase selected and the method used. Poor correlation was found between some results of this study and previously reported results of in situ absorption from the rat gastrointestinal tract of the same drugs. The results do not support the assumption that phospholipids may have a role in the absorption of ionized moieties.
通过两种不同方法，即振荡法和模型细胞实验法，研究了三种弱酸性药物（华法林、磺胺乙噻二唑和巴比妥）在环己烷 - 缓冲液体系以及正辛醇 - 缓冲液体系中的扩散情况。在低pH值时，这些药物通常比在高pH值时更容易进入有机相。此外，当使用振荡法时，即使在较高pH水平下，药物也很容易转移到正辛醇相中。卵磷脂在低pH值时比在高pH值时更能促进扩散。因此，结果因所选有机相和使用的方法而异。本研究的一些结果与先前报道的相同药物在大鼠胃肠道原位吸收的结果之间相关性较差。这些结果不支持磷脂可能在离子化部分吸收中起作用的假设。
