A capillary electrophoresis method to explore the self-assembly of a novel polypeptide ligand with quantum dots.
Electrophoresis
; 37(15-16): 2156-62, 2016 08.
Article
em En
| MEDLINE
| ID: mdl-27334251
Polyhistidine peptides are effective ligands to coat quantum dots (QDs). It is known that both the number of histidine (His) residues repeats and their structural arrangements in a peptide ligand play important roles in the assembly of the peptide onto CdSe/ZnS QDs. However, due to steric hindrance, a peptide sequence with more than six His residue tandem repeats would hardly coordinate well with Zn(2+) in the QD shell to further enhance the binding affinity. To solve this problem, a His-containing peptide ligand, ATTO 590-E2 G (NH)6 (ATTO-NH), was specifically designed and synthesized for assembly with QDs. With sequential injection of QDs and ATTO-NH into the capillary electrophoresis with fluorescence detection, strong Förster resonance energy transfer phenomenon between the QDs and the ATTO 590 dye was observed, indicating efficient self-assembly of the novel peptide onto the QDs to form ATTO-NH capped QDs inside the capillary. The binding stability of the ligand onto the QD was then systematically investigated by titrating with imidazole, His, and a his-tag containing competitive peptide. It is believed that this new in-capillary assay significantly reduced the sample consumption and the analysis time. By functionalizing QDs with certain metal cation-specific group fused peptide ligand, the QD-based probes could be even extended to the online detection of metal cations for monitoring environment in the future.
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Base de dados:
MEDLINE
Assunto principal:
Peptídeos
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Eletroforese Capilar
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Pontos Quânticos
Idioma:
En
Revista:
Electrophoresis
Ano de publicação:
2016
Tipo de documento:
Article