Hydrophilic Carotenoids: Surface Properties and Aqueous Aggregation of a Rigid, Long-Chain, Highly Unsaturated Dianionic Bolaamphiphile With a Carotenoid Spacer

Chem Phys Lipids. 2005 Jun;135(2):157-67. doi: 10.1016/j.chemphyslip.2005.02.006. Epub 2005 Mar 13.

Abstract

The water dispersibility of astaxanthin was greatly enhanced by converting it to a disodium disuccinate salt. This carotenoid salt behaved as a bolaamphiphile in water; dynamic light scattering (DLS) revealed the formation of stable aggregates with an average hydrodynamic radius close to 1 microm. Larger aggregates were observed in solutions of increased osmolarity. Absorption spectra demonstrated that the aggregates could withstand the addition of 20% acetonitrile before disintegrating to monomers. The physicochemical properties of this astaxanthin derivative in solution were comprehensively studied by measuring surface tension, critical aggregate concentration, surface concentration, molecule area, free energy of adsorption and micellation, adsorption-aggregate energy relationship, and equilibrium constants, and then compared with similar compounds reported previously in the literature.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carotenoids / chemistry*
  • Food Coloring Agents / chemistry*
  • Solubility
  • Surface Properties
  • Surface-Active Agents / chemistry
  • Water

Substances

  • Food Coloring Agents
  • Surface-Active Agents
  • Water
  • Carotenoids