Synthesis and characterization of NVOC-DOPE, a caged photoactivatable derivative of dioleoylphosphatidylethanolamine

A caged, photocleavable derivative of dioleoylphosphatidylethanolamine (DOP E) called NVOC-DOPE was prepared by reaction of DOPE with 6-nitroveratrylox ycarbonyl chloride. In contrast to egg phosphatidylethanolamine (EPE), NVOC -DOPE or its 1:1 mixture with EPE forms liposomes at both pH 7.4 and 5.0. P hotolysis (lambda > 300 nm) of aqueous liposomal dispersions of NVOC-DOPE a t pH 9.0, 7.4, or 5.0 results in complete conversion to DOPE and subsequent release of entrapped calcein dye. The temporal and spatial control associa ted with the photorelease technique suggests that NVOC-DOPE can be used to study a range of important; dynamic membrane processes such as membrane fus ion and the action of membrane-associated enzymes.