Freeze-fracture electron microscopy on nanostructures for drug & gene delivery

The morphology of a variety of nanostructures suitable for drug and/or gene delivery such as liposomes, niosomes, cochleate cylinder, depofoam particles, and liposome/DNA complexes has been studied under biologically relevant conditions by using freeze-fracture electron microscopy. This study shows that freeze-fracture electron microscopy is not only a powerful technique to characterize drug/gene carrier but also the method of choice to study their fate related to the incubation milieu and drug/gene load, and during their interaction with cells on a nanometer resolution scale. Furthermore, parallel studies of the morphology and transfection activity help us to understand the fundamental difference between in vitro and in vivo transfection activity of cationic liposome/ DNA complexes as non-viral gene vectors.