High-Affinity Labeling and Tracking of Individual Histidine-Tagged Proteins in Live Cells Using Ni²⁺ Tris-nitrilotriacetic Acid Quantum Dot Conjugates

Abstract

Investigation of many cellular processes using fluorescent quantum dots (QDs) is hindered by the nontrivial requirements for QD surface functionalization and targeting. To address these challenges, we designed, characterized and applied QD-trisNTA, which integrates tris-nitrilotriacetic acid, a small and high-affinity recognition unit for the ubiquitous polyhistidine protein tag. Using QD-trisNTA, we demonstrate two-color QD tracking of the type-1 interferon receptor subunits in live cells, potentially enabling direct visualization of protein-protein interactions at the single molecule level.

Quantum Dots (QDs) for Tumor Targeting Theranostics

“…Highly stable ligand-QD conjugates mimicking viruses and pathogenic microorganisms can be modeled to characterize the immune response mechanisms in details. For example, Roullier et al 124 functionalized QDs with a chelator, tris-nitrilotriacetic acid (tris-NTA), pre-loaded with Ni for labeling of biomolecules with ubiquitous HIS tags.…”

Nanoparticles Containing Rare Earth Ions: A Tunable Tool for MRI

“…Their relatively narrow emission band whose position is controlled either by the particle size or, for a given size, by tuning the composition of the alloyed semiconducting QD (CdSeTe), together with their broad absorption spectra offer a large palette of distinct color enabling multilabeling [83]. Since several synthetic routes have been developed for the preparation of water-soluble QDs with narrow size distribution and high quantum yields, the literature is overflowing with examples of biological materials labeled by QDs [84,85]. Indeed, the most common synthetic routes of QDs lead to hydrophobic fluorescent nanoparticles since they are coated by trioctylphosphine/ trioctylphosphine oxide (TOP/TOPO).…”

Synthesis, biocompatibility and cell labeling of l-arginine-functional β-cyclodextrin-modified quantum dot probes

“…QDs are a novel class of fluorescent probes with unique optical properties. They are superior to conventional organic dyes used in many biological applications such as labeling both fixed and living cells [7][8][9][10][11]. Their robust water-solubility is essential when used as probes for examining biological specimens.…”