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Self-assembling nanostructures were prepared from novel cationic amphiphilic compounds synthesized from vernonia oil, a natural epoxydized triglyceride. The presence of a 12,13-epoxy group on the C18 unsaturated fatty acid, vernolic acid, which is the main constituent of vernonia oil, permitted the synthesis of novel amphiphilic derivatives with a hydrogen-bonding hydroxyl and a cationic headgroup moiety on adjacent carbon atoms. The amphiphiles were prepared in a two-stage synthesis that comprised opening of the epoxy groups with a haloacetic acid, followed by quaternization of the halo group with a tertiary amine containing a C12 aliphatic chain. Intact vernonia oil as the starting material gave a triple-headed cationic amphiphile, containing three vernolic acid derived moieties connected through a glycerol backbone. A single-headed amphiphile with two alkyl chains and a single quaternary ammonium headgroup was synthesized from the methyl ester of vernolic acid as the starting material. The triple-headed derivative could form nonencapsulating structures. Cholesterol was required in the formulation (1:1) to make spherical vesicles that could encapsulate a water-soluble marker. The single-headed derivative, however, formed spherical encapsulating vesicles without cholesterol. TEM, NMR, and FT-IR were used to characterize the vesicles, and molecular structure vs morphology relationships were postulated on the basis of these data. The triple-headed amphiphile also formed a DNA complex that was highly resistant to hydrolysis by DNase. This amphiphile-DNA complex was used as vector for gene transfer in cell culture demonstrating efficient DNA transfection.

Throughout the ages, fats, oils and their chemical derivatives have been used in a variety of medical applications, but currently they are becoming important as components in drug delivery systems. Liposomes (vesicles from phospholipids) are among the lipid-based delivery systems that have been most extensively studied. However, targeting of liposomes to specific tissues is still problematic, and attempts to overcome these limitations include developments in nano-sized monolayer vesicles made of bolaamphiphiles (compounds containing two hydrophilic headgroups at each end of an alkyl chain). This paper describes bolaamphiphile synthesis and characterization of the nano-sized vesicles formed from the bolaamphiphiles with potential application for targeted drug delivery to the brain. The starting material for the synthesis is vernonia oil (or its fatty acids or methyl esters), which is a naturally epoxidized triacylglycerol obtained from the seeds of Vernonia galamensis. The targeting mechanism is based on the hydrolysis of the amphiphile's headgroup by an enzyme abundant in the target tissue, with subsequent release of the encapsulated drug at the target site. Preliminary experiments in mice demonstrated that the marker FITC-dextran, which normally does not penetrate the blood brain barrier, is delivered into the brain when encapsulated in these vesicles.

Acrylate and methacrylate monomers were obtained by reacting vernonia oil, a naturally epoxidized oil, with acrylic or methacrylic acid. The highest conversion (85-98%) of epoxy groups was obtained when the reaction was performed with an excess of the carboxylic acid at 100 -120°C. The acrylate and methacrylate monomers of vernonia oil were characterized by IR and NMR spectroscopy. These monomers were then cured by sunlight in the presence of benzophenone to produce transparent films. In addition, interpenetrating polymer neworks (IPNs) were prepared in a two-step technique from the sunlight-cured methacrylate of vernonia oil, as the elastomeric component, in combination with a cured epoxy resin (a bisphenol A-type resin). Dynamic mechanical analysis showed good compatibility between the networks of the two cured polymers. An IPN with a 1 : 1 composition of the two polymer components exhibited the properties of a reinforced elastomer.

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