Relevance of the chlorophyll phytyl chain on lamellar phase formation and organisation.

A series of modified chlorophylls (chlorophyll a, pyrochlorophyll a, Zn-pheophytin a and Zn-pheophorbide a) have been inserted into lamellar phases of sodium bis-(2-ethylhexyl)-sulfosuccinate (AOT). The role played by the different functional groups in affecting the bilayer formation and organisation has been investigated by means of the NMR quadrupolar splitting technique. Evidence is reported for the first time on the capacity of the phytyl chain of the chlorophylls to anchor the tetrapyrroles into the bilayer, favouring at the same time the regular formation of the lamellae.