Bifunctional Peptide-Conjugated Gold Nanoparticles for Precise and Efficient Nucleus-Targeting Bioimaging in Live Cells

Anal Chem. 2020 Oct 6;92(19):13595-13603. doi: 10.1021/acs.analchem.0c03476. Epub 2020 Sep 17.

Abstract

Real-time in situ imaging of organelles is increasingly important in modern biomedical analysis and diseases diagnosis. To realize this goal, organelle-targeting nanoparticles as one of the most commonly used technologies in subcellular sensing and imaging has attracted a lot of interest. The biocompatibility, specificity, and binding efficiency are especially critical for efficient organelle-targeting bioimaging. Gold nanoparticles (AuNPs) fabricated with bifunctional peptides constructed with both Au-binding affinity and nucleus-targeting ability were designed and examined for efficient nucleus-targeting bioimaging. Such a design is expected to achieve an oriented assembling of peptides by the medium of the Au-binding peptides specifically assembled on the surface of AuNPs, with the nucleus-targeting end open for accessibility. The bifunctional peptides showed strong binding affinity toward AuNPs and led to a binding capability ∼1.5 times higher than that of the bare nucleus-targeting peptides, ensuring good surface coverage of the nanoparticles for enhanced nucleus-targeting ability. Such fabricated AuNPs demonstrated over 90% cell viability after incubation for 24 h with HepG2 cells, which were highly biocompatible. Precise and efficient bioimaging of the nucleus was achieved for HepG2 cells by using the fabricated AuNPs as observed with a confocal laser scanning microscope, a dark-field/fluorescence microscope, and a transmission electron microscope. The high surface coverage and oriented binding pattern appeared to be a promising strategy for construction of organelle-targeting agencies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Nucleus / chemistry*
  • Cell Nucleus / metabolism
  • Cell Survival / drug effects
  • Gold / chemistry*
  • Gold / pharmacology
  • Humans
  • Metal Nanoparticles / chemistry*
  • Particle Size
  • Peptides / chemistry*
  • Peptides / pharmacology
  • Spectrometry, Fluorescence
  • Surface Properties
  • Tumor Cells, Cultured

Substances

  • Peptides
  • Gold