Table IV.

Surfactant Solubilization Parameters for Repaglinide and Glitazones

Drug/surfactant	Solubilization parameters
	Water			0.15 M NaCl			Buffer
	χ	K	a	χ	K	a	χ	K	a
Repaglinide
SDS	36.77	20.90	−7.53	43.64	24.80	−7.96	–	–	–
CTAB	35.18	19.99	−7.42	34.45	19.58	−7.37	643.23	365.53	−14.62
T-80	41.58	23.63	−7.84	39.65	22.53	−7.72	266.80	151.61	−12.44
SDS + T-80	52.23	29.68	−8.40	38.87	22.09	−7.67	–	–	–
CTAB + T-80	19.74	11.22	−5.99	44.42	25.24	−8.00	562.91	319.88	−14.29
Pioglitazone
SDS	20.53	28.71	−8.32	22.96	32.11	−8.60	–	–	–
CTAB	3.85	5.39	−4.17	6.83	9.55	−5.59	51.62	72.19	−10.60
T-80	3.50	4.89	−3.93	5.01	7.01	−4.82	0.63	0.88	+0.32
SDS + T-80	28.10	39.29	−9.10	358.93	501.94	−15.41	–	–	–
CTAB + T-80	8.31	11.62	−6.08	123.05	172.07	−12.76	9.16	12.81	−6.32
Rosiglitazone
SDS	19.03	14.69	−7.53	22.99	17.75	−7.96	–	–	–
CTAB	20.33	15.69	−7.42	25.19	19.45	−7.37	130.68	100.87	−14.62
T-80	18.38	14.19	−7.84	16.28	12.56	−7.72	14.13	10.91	−12.44
SDS + T-80	5.82	4.49	−8.40	347.29	268.07	−7.67	–	–	–
CTAB + T-80	16.51	12.75	−5.99	308.63	238.22	−8.00	43.00	33.19	−14.29

^a χ has been expressed as millimoles of drug solubilized per mole surfactant and values are in kilojoules per mole at 298.15 K