Abstract
•Phase separation of TX-100 + promethazine hydrochloride (PMH) was studied in presence of salts.•Assembly of TTAB + PMH drug has been investigated at different temperatures.•CP of TX-100 + PMH mixture in salts media, follow the order: K3PO4 < K2SO4 < KCl.•Thermodynamic parameters (phase separation/aggregation processes) are computed.•Phase separation/aggregation of system was found nonspontaneous/spontaneous.
Here, the phase separation of the mixture of triton X-100 (TX-100) and promethazine hydrochloride (PMH), as well as the assembly of the mixture of tetradecyltrimethylammonium bromide (TTAB) and PMH drug, have been investigated. The cloud points (CP) of TX-100 in the manifestation of PMH/PMH + salts (KCl, K2SO4, and K3PO4) were determined, while the CP values were found to vary with the contents of PMH and salts. The CP of TX-100 + PMH mixture, at a particular PMH concentration in salts media, follow the order: K3PO4 < K2SO4 < KCl. The micellar parameters were determined from the conductivity versus [TTAB] plots. The conductivities and micellar parameters of the TTAB + PMH mixture in salts media were found to vary through the fluctuation of temperature. The thermodynamic variables (free energy (ΔG0), enthalpy (ΔH0), and entropy (ΔS0) changes) for the phase separation and aggregation phenomena of the mixture of surfactant + drug mixture have been computed in the current studies. The phase separation of TX-100 + PMH mixtures was nonspontaneous (+ΔG0c values) and assembly of the TTAB + PMH mixture was spontaneous (–ΔG0m values). The other thermodynamic variables, in addition to enthalpy–entropy compensation parameters, have also been evaluated and illustrated with proper explanation.