Table 1.
Plant origins and physicochemical parameters of model drugs
| Active component | Main plant origin | logK o/w at 32 °C | MW | Solubility in water at 32 °C (mg/ml) | pK a |
| Osthole | Cnidii Fructus (Shechuangzi); Angelicae Pubescentis Radix (Duhuo) | 3.85 | 244.34 | 1.32×10−3 | |
| Tetramethylpyrazine | Chuanxiong Rhizoma (Chuanxiong) | 2.34 | 136.20 | 4.72 | 3.20 |
| Ferulic acid | Angelicae Sinensis Radix (Danggui); Cimicifugae Rhizoma (Shengma) | 1.26 | 194.18 | 0.54 | 4.58 |
| Puerarin | Puerariae Lobatae Radix (Gegen) | −0.35 | 432.38 | 3.64 | 6.46 |
| Geniposide | Gardeniae Fructus (Zhizi); Eucommiae Cortex (Duzhong) | −1.01 | 388.37 | 481.87 | 12.80 |
K o/w: n-octanol/water partition coefficient; MW: molecular weight; pK a: acidity strength, from the SciFinder database