Non-covalent associations of cyclomaltooligosaccharides (cyclodextrins) with carotenoids in water.: A study on the α- and β-cyclodextrin/ψ,ψ-carotene (lycopene) systems by light scattering, ionspray ionization and tandem mass spectrometry

Water-soluble complexes of the dietary carotenoid, psi,psi-carotene (lycopene 1) with cyclomaltohexaose (alpha-cyclodextrin, alphaCD) and cyclomaltoheptaose (beta-cyclodextrin, betaCD) have been prepared and characterized via multiangle light scattering (MALS), ionspray/electrospray ionization (IS/ESI) mass spectrometry (MS) and tandem MS. MALS experiments point out that large aggregates of particles, on the nanometer-size scale, are present in water, with meaningful differences in the shape of the alphaCD/1 aggregates with respect to betaCD/1 analogues. The true 1:1 alphaCD/1 inclusion complex has been observed by IS/ESIMS and confirmed by tandem MS. The structure of CD/1 aggregations in water is proposed which are consistent with the combined MALS and MS experimental results. (C) 2002 Elsevier Science Ltd. All rights reserved.