Abstract
Herein, we have examined the interaction between promazine hydrochloride (PMZ) with bile salts (sodium cholate (NaC) and sodium deoxycholate (NaDC)) at different temperatures and compositions using conductometric method. The critical micelle concentration (cmc) value of pure PMZ and bile salts were also evaluated by tensiometric method. The cmc values attained by the two methods are close to each other. Various physicochemical parameters like cmc, ideal cmc (cmc
id
), degree of dissociation of counterion (g), micellar mole fractions of bile salt (
,
,
), micellar mole fraction of bile salt in ideal state (
), interaction parameter (β
m
), activity coefficients (f
1
, f
2
), standard Gibbs free energy (
), enthalpy (
), entropy of micellization (
), and excess free energy of mixing (ΔG
ex
) of the mixed micelles have been evaluated and discussed in detail using Clint's, Rubingh's, Motomura's, and Rodenas's models. NaDC is more efficient in decreasing the cmc of PMZ as compared to NaC because it binds strongly to PMZ ions and more decreases the head group area of drug. On the whole, this lesson might find application in the fundamental science of the physical chemistry of amphiphilic systems, as well as in the research of drug delivery system.