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Updated: May 17, 2026

Fluorescent Leakage Assay to Investigate Membrane Destabilization by Cell-Penetrating Peptide
Published on: December 19, 2020
Intracellular fate of peptide-mediated delivered cargoes
Irene Martín1, Meritxell Teixidó, Ernest Giralt
1Institute for Research in Biomedicine (IRB Barcelona), Barcelona Science Park, Baldiri Reixac 10, 08028 Barcelona, Spain.
Abstract:
Cell-penetrating peptides (CPPs) are promising tools for intracellular delivery. However, no consensus regarding their internalization mechanism has been reached within the scientific community. Although endocytosis seems to be the preferred internalization mechanism for most CPP-cargo complexes, examples of direct translocation have also been identified. In this review we go through the several ways of studying CPP-mediated cargo delivery in cells and the possible factors affecting the internalization pathways followed by these complexes. In addition, we analyze the CPP-mediated delivery of two relevant cargoes, namely quantum dots and nucleic acids, focusing on the internalization mechanism that they follow.
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