The alterations in the absorption and fluorescence spectra observed for the polyene
antibiotics filipin and nystatin in the presence of cholesterol are due to an exciton interaction
(polyene aggregates) and cannot be attributed to a specific sterol-antibiotic complex. Filipin
and nystatin molecules partition into the sterol aggregates, these structures being very
efficient to induce exciton interaction; the observed splitting profile indicates that the
chromophores are in a stacked arrangement (parallel transition dipoles). For filipin …