Self-assembled quantum dot-peptide bioconjugates for selective intracellular delivery.

摘要: We demonstrate the use of self-assembled luminescent semiconductor quantum dot (QD)-peptide bioconjugates for selective intracellular labeling several eukaryotic cell lines. A bifunctional oligoarginine penetrating peptide (based on HIV-1 Tat protein motif) bearing a terminal polyhistidine tract was synthesized and used to facilitate transmembrane delivery QD bioconjugates. The sequence allows self-assemble onto surface via metal-affinity interactions while specific across cellular membrane as compared nonconjugated QDs. This peptide-driven is concentration-dependent thus can be titrated. Upon internalization, QDs display punctate-like staining pattern in which some, but not all, signal colocalized within endosomes. effects constant versus limited exposure QD-peptide conjugates viability are evaluated by metabolic assay, clear differences cytotoxicity observed. efficacy using peptides highlighted performing multicolor labeling, where we found that presence or absence controls uptake.