Solubility enhancement of anthracene and pyrene in the mixtures of a cleavable cationic gemini surfactant with conventional surfactants of different polarities

In this study, the solubilization of anthracene and pyrene was investigated in micellar solutions of ethane-1,2-diyl bis(N,N-dimethyl-N-dodecylammoniumacetoxy) dichloride (C12H25(CH3)2N+(CH2COOCH2)2N+(CH3)2C12H25·2Cl−, 12-E2-12) and its equimolar binary mixtures of conventional cationic, anionic and nonionic surfactants in water. Critical micelle concentration (cmc) and other physicochemical parameters were determined by the surface tension and conductivity measurements at 30 °C. Much lower cmc value was obtained for 12-E2-12 than the corresponding monomeric surfactant dodecyltrimethylammonium chloride (DTAC). Lower experimental cmc than the ideal cmc and the negative interaction parameters imply synergistic interaction between the surfactants in the binary solutions. Order of solubilization capacity of the pure/mixed surfactant micelles, for anthracene and pyrene, are not the same. Among the pure surfactants, Brij 58 has highest and SDBS has least efficiency for dissolution of the solutes. The mixed systems 12-E2-12 + SDS and 12-E2-12 + Brij 58 have highest dissolution power for anthracene and pyrene, respectively. Solubility enhancement was observed for both the solutes in the equivalent binary mixtures of the dicationic gemini 12-E2-12 with the anionic conventional surfactants SDS and SDBS. To determine the toxicity of 12-E2-12 and to quantify its interaction with erythrocytes, we have performed the hemolytic assessment. As regards the hemolytic activity and biodegradability test, 12-E2-12 is less toxic and readily biodegradable.