Enhancing solubilization of Nebivolol hydrochloride through tuning pluronic F-127 with ionic Surfactants: An experimental and theoretical investigation

Abstract

In the present work, the interaction of the antihypertensive drug Nebivolol hydrochloride (NBL) with nonionic surfactant pluronic F-127 (F-127) is investigated in an aqueous medium. Two ionic surfactants, viz., cationic, cetyl trimethyl ammonium bromide (CTAB) and anionic, sodium tetradecyl sulphate (STS) were added to F-127 to improve the physicochemical properties of the single micellar medium. The characterization techniques employed were, FTIR, UV–visible spectroscopy, dynamic light scattering, zeta potential, antioxidant, conductivity, and FESEM studies. The critical micellar concentration (CMC) of CTAB and STS are estimated from the conductivity experiments which is lowered due to the addition of F-127 and NBL. The lowering of CMC is attributed to the solubilization of NBL in the binary micellar mediums. The extent of binding of NBL in F-127, F-127 + CTAB, and F-127 + STS were quantified by determining the binding constant values using the Benesi–Hildebrand (B-H) plot from UV absorbance data. They were, 838.2 M−1 for F-127 1100.7 M−1 for F-127 + CTAB and 1836.5 M−1 for F-127 + STS systems. There was an increase in the size of the micelle due to the encapsulation of the drug in both binary micellar systems. The zeta potential (ZP) values displayed enhanced stability of the drug in binary micellar systems. The radical scavenging activity (RSA %) of NBL was estimated to be 16.5 % in F-127, 24.7 % in F-127 + CTAB, and 44.9 % in F-127 + STS systems. The encapsulation efficiency (EE %) for the above three systems were 14.7 %, 16.4 % and 18.5 %, respectively. The surface parameters and the interactions were verified through molecular docking studies. The results suggest that the properties of F-127 can be improved by tuning with ionic surfactants to solubilize NBL. To our knowledge, this is the first report of NBL solubilization in mixed micellar systems. Similar studies with other drug systems can be applied to get improved results.