Constrained cell penetrating peptides

In this review we provide an overview of recent developments in the field of cell penetrating peptides (CPPs) on research that aims to achieve better control over their transduction properties - one of the big challenges - by means of restraining them. Three different constraining strategies are presented: triggerable activation, backbone rigidification and macrocyclization. Each of these methods have their opportunities in gaining control over CPP activity and selectivity.