TABLE 1

Determination of λ based on the pH-dependent permeation data of statins observed in Caco-2 cells

Values are shown as the mean ± S.D.

Drug	f_i,ion^{^a}	f_i,uion^{^a}	f_o,ion^{^a}	f_o,uion^{^a}	pKa^{^b}	PS_{dif,inf,uion,Caco-2}^{^c}× 10⁻⁶	λ^{^c}
						µL/min/well
Pitavastatin	0.857	0.143	0.905	0.095	4.46	3487 ± 1403	0.0282 ± 0.0204
Rosuvastatin	0.986	0.014	0.991	0.009	4.6	714 ± 68	0.0112 ± 0.0035
Pravastatin	0.986	0.014	0.991	0.009	4.6	111 ± 19	0.188 ± 0.038

↵^a The f_i,ion and f_o,ion were calculated based on Henderson–Hasselbalch equation assuming that intracellular pH and medium pH are 7.2 and 7.4, respectively. The f_i,uion and f_o,uion were subtracted f_i,ion and f_o,ion from one, respectively.
↵^b Fixed at values obtained from the manufacturer’s Interview Forms.
↵^c The PS_{dif,inf,uion,Caco-2} and λ were determined by fitting eq. 9 to the pH-dependent permeation data of statins observed in Caco-2 cells (Supplemental Fig. 1).