Cellular internalization and targeting of semiconductor quantum dots

Abstract

Peptide-mediated internalization and organelle targeting of quantum dots.

Peptides for Specific Intracellular Delivery and Targeting of Nanoparticles: Implications for Developing nanoparticle-mediated Drug Delivery

“…The NP must present the requisite positively/negatively charged surface with the peptide having the opposite characteristics. Naik and co-workers showed that this approach could even be used to deliver QDs to cells [25]. The positively charged lysine-rich 21-residue Pep-1 peptidyl sequence was noncovalently associated with commercial streptavidin-conjugated CdSe/ZnS core/shell QDs, which facilitated their delivery to HeLa cells.…”

“…This QD-based barcoding approach, mediated by Pep-1 QD delivery, has applications for multiplexed cellbased drug-discovery assays and, more generally, for studies using mixed cell populations (e.g., tissue engineering). The work of Rozenzhak is another elegant example of a Pep-1-directed QD cell-labeling study with implications for targeted cancer therapy/therapeutic peptide delivery [25]. The authors used commercially available streptavidin-conjugated QDs decorated with both a biotinylated Pep-1 peptide and the pro-apoptotic GH3 peptide to induce apoptosis in vitro.…”

“…A subsequent mixed-surface approach combined biotinylated peptides with the electrostatically associated Pep-1 to achieve either organelle targeting or apoptotic triggering and highlighted the versatility of this approach. The authors suggested that the Pep-1 carrier initially associated with the QD conjugates to allow initial interactions and crossing of the cell membrane and then dissociated from the complex, thus permitting further intracellular targeting [25]. Electrostatic chemistry has also been applied to negatively charged citrate-stabilized Au-NPs partnered with a positively charged coiled peptide and pH changes were even used as a trigger to alter the electrostatics and control assembly kinetics [26].…”

Self-Assembled Quantum Dot−Peptide Bioconjugates for Selective Intracellular Delivery

“…Lagerholm attached 25-to 50-fold excess of a biotinylated 9-mer poly-arginine containing peptide to streptavidin QDs and found intracellular labeling in Swiss 3T3, HeLa and MG63 cells with a brightness two orders of magnitude stronger than unconjugated QDs alone (8). Rozenzhak used a noncovalently complexed 21-residue peptide carrier for cellular delivery of QDs into HeLa cells (9). This peptide, which is believed to function independently of endocytosis, consists of a hydrophobic tryptophan-rich domain for efficient membrane translocation and a lysine-rich domain for solubility.…”

Pep-1 Peptide-Modified Liposomal Carriers for Intracellular Delivery of Gold Nanoparticles

“…Several strategies have been reported for the intracellular delivery of metallic nanoparticles, including microinjection, 33) cationic transfection reagents, 34) CPPs introduction, 35,36) and electroporation. 37) Although these techniques facilitate better transport of Au NPs to the cells, they present certain problems such as a limited throughput process in microinjection requiring simultaneous manipulation of individual cells and invasive damage to cellular membranes in electroporation.…”