title: Three Arginine-Rich Cell-Penetrating Peptides Facilitate Cellular Internalization of Red-Emitting Quantum Dots.
abstract: 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 deliv- ery 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.
authors.forename: Betty R
authors.initials: BR
authors.lastname: Liu
authors.forename: Hwei-Hsien
authors.initials: HH
authors.lastname: Chen
authors.forename: Ming-Huan
authors.initials: MH
authors.lastname: Chan
authors.forename: Yue-Wern
authors.initials: YW
authors.lastname: Huang
authors.forename: Robert S
authors.initials: RS
authors.lastname: Aronstam
authors.forename: Han-Jung
authors.initials: HJ
authors.lastname: Lee
mesh_terms: D001120:Arginine; D001692:Biological Transport; D045744:Cell Line, Tumor; D057846:Cell-Penetrating Peptides / Q000737:chemistry*; D003116:Color; D006801:Humans; D042541:Intracellular Space / Q000378:metabolism; D045663:Quantum Dots / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D057846:Cell-Penetrating Peptides; D001120:Arginine