Purification of peroxisomes using a density barrier in a swinging-bucket rotor

In iodixanol, peroxisomes are the densest organelle in the light mitochondrial fraction and are therefore easily separated from the other components (lysosomes, mitochondria, etc.) in a preformed isosmotic continuous gradient. Because of the large difference in density between peroxisomes and the next densest organelle (mitochondria), a density barrier is effective. The resolution of the peroxisomes is far superior than that in sucrose and, unlike in Percoll, there is no contamination from endoplasmic reticulum.