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Updated: Oct 5, 2025

Fluorescent Leakage Assay to Investigate Membrane Destabilization by Cell-Penetrating Peptide
Published on: December 19, 2020
An update on cell-penetrating peptides with intracellular organelle targeting
Carmine Pasquale Cerrato1, Ülo Langel2,3
1Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden.
Introduction:
Cell-penetrating peptide (CPP) technologies represent an important strategy to address drug delivery to specific intracellular compartments by covalent conjugation to targeting sequences, potentially enabling strategies to combat most diseases.
Areas Covered:
This updated review article provides an overview of current intracellular organelle targeting by CPP. The targeting strategies of CPP and CPP/cargo complexes to specific cells or intracellular organelles are summarized, and the review provides an update on the current data for their pharmacological and therapeutical applications.
Expert Opinion:
Targeted drug delivery is moving from the level of tissue or specific pathogenic cell to the level of specific organelle that is the target of the drug, an important aspect in drug design and development. Organelle-targeted drug delivery results in improved efficacy, ability to control mode of action, reduction of undesired toxicities and side effects, and the possibility to overcome drug resistance mechanisms.
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