物理化学学报 >> 2011, Vol. 27 >> Issue (08): 1900-1906.doi: 10.3866/PKU.WHXB20110817
KABIR-UD-DIN, KHAN Abbul Bashar, NAQVI Andleeb Z.
KABIR-UD-DIN, KHAN Abbul Bashar, NAQVI Andleeb Z.
摘要:
The behavior of the mixed amphiphilic drug promethazine hydrochloride (PMT) and cationic as well as nonionic surfactants was studied by tensiometry. The cmc values of the PMT-surfactant systems decrease at a surfactant mole fraction of 0.1 and it then becomes constant. The critical micelle concentration (cmc) values are lower than the ideal cmc (cmc*) values for PMT/TX-100, PMT/TX-114, PMT/Tween 20, and PMT/Tween 60 systems. For the PMT/Tween 40, PMT/Tween 80, PMT/CPC, and PMT/CPB systems the cmc values are close to the cmc* values. This indicates that PMT forms mixed micelles with these surfactants by attractive interactions. The surface excess (Γmax) decreases in the presence of surfactants. The rigid structure of the drug makes adsorption easier and the contribution of the surfactant at the interface decreases. The interaction parameters βm (for the mixed micelles) and βσ (for the mixed monolayer) are negative indicating attraction among the mixed components.