Spectrophotometric study of quercetin in metallomicellar solutions of 1-hexadecyl-4-aza-1-azoniabicyclo[2.2.2]octane bromide complex with copper dibromide

The influence of 1-hexadecyl-4-aza-1-azoniabicyclo[2.2.2]octane bromide (D-16) complex with copper dibromide ([D-16 x CuBr2]) on the solubility of quercetin has been investigated by spectrophotometric method. High solubilization activity of the system in both premicellar and post-critical micelle concentration (CMC) ranges of complex concentrations was found. Analysis of spectral data strongly supports the interaction of metallosurfactant with quercetin and testifies the partial modification of the drug, including the complexation of quercetin with a copper cation below and above the CMC and the oxidation of the drug in micellar solutions. Solubilization of the drug in [D-16 x CuBr2] micelles is accompanied by changes in size behavior of aggregates of the complex. (C) 2017 Elsevier B.V. All rights reserved.