Hasegawa J, Fujita T, Hayashi Y, Iwamoto K, Watanabe J
J Pharm Sci. 1984 Apr;73(4):442-5. doi: 10.1002/jps.2600730405.
The pKa of verapamil was determined by measuring the partition coefficient of verapamil between n-heptane and aqueous buffer solution at various pH values. The magnitude of the effects of ionic strength or temperature on the pKa of verapamil was in agreement with those reported previously. The estimated pKa of verapamil in human plasma was 8.75. The pKa of 2,4,6-trimethylpyridine measured by means of the present partition method was in good agreement with that determined by UV spectrophotometry.
通过测量维拉帕米在不同pH值下于正庚烷和水性缓冲溶液之间的分配系数来测定其pKa。离子强度或温度对维拉帕米pKa的影响程度与先前报道的一致。人血浆中维拉帕米的估计pKa为8.75。用本分配方法测得的2,4,6 - 三甲基吡啶的pKa与通过紫外分光光度法测定的结果高度一致。
