Purification of non-synaptic and synaptic mitochondria and plasma membranes from rat brain by a rapid Percoll gradient procedure.

A method is described for the isolation and purification of non-synaptic and synaptic mitochondria and plasma membranes. The procedure involved differential centrifugation and successively a Ficoll gradient followed by a Percoll one. The method is rapid and maintains constant osmotic conditions. The Percoll-purified fractions show a lower density than those prepared by the conventional methods. The fractions were identified and characterized by enzyme markers and electron microscopy. The method will be useful for routine preparations rendering a good degree of homogeneity and purity.