Properties of chlorophyll on plasticized polyethylene particles.

There are several reasons for suspecting that there is a specific interaction between chlorophyll and galactolipids in the chloroplast. The model system described is intended to detect association of chlorophyll with polar lipids and other surfactants at a hydrocarbon-water interface. It consists of chlorophyll and other lipids or surfactants absorbed to the surface of polyethylene particles, which have been swelled with undecane to allow the lipophilic parts of these molecules to be anchored firmly in the hydrocarbon substrate. The absorption spectrum of adsorbed chlorophyll is usually modified by the presence of surfactant, and usually in the direction of decreased order of aggregation. Spectra in the presence of glycolipids in particular seem peculiar to the surfactant. The particles are strongly fluorescent, at room temperature as well as at 77K, and emission bands from aggregated chlorophyll species are observed along with fluorescence of monomeric chlorophyll.