Three Arginine-Rich Cell-Penetrating Peptides Facilitate Cellular Internalization of Red-Emitting Quantum Dots


Nanoparticles, such as semiconductor quantum dots (QDs), have been found increasing use in biomedical diagnosis and therapeutics because of their unique properties, including quantum confinement, surface plasmon resonance, and superparamagnetism. Cell-penetrating peptides (CPPs) represent an efficient mechanism to overcome plasma membrane barriers and deliver biologically active molecules into cells. In this study, we demonstrate that three arginine-rich CPPs (SR9, HR9, and PR9) can noncovalently complex with red light emitting QDs, dramatically increasing their delivery into living cells. Zeta-potential and size analyses highlight the importance of electrostatic interactions between positive-charged CPP/QD complexes and negative-charged plasma membranes indicating the efficiency of transmembrane complex transport. Subcellular colocalization indicates associations of QD with early endosomes and lysosomes following PR9-mediated delivery. Our study demonstrates that nontoxic CPPs of varied composition provide an effective vehicle for the design of optimized drug delivery systems.


Biological Sciences

Keywords and Phrases

Amino Acids; Arginine; Biomedical Engineering; Cell Membranes; Cells; Cytology; Drug Delivery; Light Emission; Nanocrystals; Nanoparticles; Peptides; Surface Plasmon Resonance; Biologically Active Molecules; Biomedical Diagnosis; Cell Penetrating Peptides (CPPs); Cellular Internalization; Drug Delivery System; Polyarginine; Protein Transduction; Semiconductor Quantum Dots; Chemistry; Color; Intracellular Space; Metabolism; Transport at the Cellular Level; Tumor Cell Line; Biological Transport; Cell Line, Tumor; Humans; Quantum Dots

International Standard Serial Number (ISSN)

1533-4880; 1533-4899

Document Type

Article - Journal

Document Version


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© 2015 American Scientific Publishers, All rights reserved.

Publication Date

01 Mar 2015

PubMed ID