Table 2.

The permeability level of different concentrations of morphine in the presence of MDCK II.

Morphine Concentration* (μg/ml)	Permeability ± SD (106 cm/s)
61.82	27.86 ± 1.22
100.0	30.88 ± 1.34
200.0	42.94 ± 4.57
400.0	54.60 ± 1.77

^*Hank’s buffer was as working buffer