Mitochondrial targeting of a cationic amphiphilic polyproline helix.

The development of cell penetrating peptides (CPPs) for the cellular delivery of attached cargo is an area of growing interest. Many CPPs, however, are found trapped within endosomes, thereby limiting their use as drug delivery agents with sub-cellular applications. Herein, we detail the properties of a highly efficient class of CPPs, cationic amphiphilic polyproline helices (CAPHs), that are found localized to the mitochondria by direct transport into cells.