Interactions of tricyclic antidepressant drug chlomipramine hydrochloride with imidazolium based surface active ionic liquid in aqueous solution

[Display omitted] •Formation of thermodynamically stable mixed micelles of CLP and [C8mim][Cl].•Values of TΔSM0 are higher than the ΔHM0 specifying entropy controlled micellization.•Activity coefficients ƒ1 and ƒ2 being small signifying non-ideality of mixed system.•|β|> |ln (cmc1/cmc2) |and ΔGM0 and ΔGex both found to be negative.•Interaction parameter, β, negative confirming synergistic interactions. Tricyclic antidepressant drug, Chlomipramine hydrochloride (CLP) with surface active ionic liquid (SAIL), 1-octyl-3-methylimidazolium chloride, was investigated using electrical conductivity. Various theoretical models were employed to calculate various interaction parameters and thermodynamic parameters. Different mole fractions of CLP with SAIL were studied to evaluate the critical micelle concentration (CMC) using electrical conductivity measurements. The change in Gibbs free energy of micellization, change in enthalpy of micellization, change in entropy of micellization, micellar mole fraction, χ1, of the CLP, and the interaction parameter, β, activity coefficients ƒ1 and ƒ2were calculated. The χIdeal and χ1 values were observed to increase on increasing the mole fraction of CLP from 0.4 to 0.6. This may be an indication of drug molecules being adsorbed on the micellar surface. As a result the mixed system (CLP and SAIL) were found to form stable mixed micelles.