Dextran-Functionalized Semiconductor Quantum Dot Bioconjugates for Bioanalysis and Imaging.
Kelly ReesMichael V TranMelissa MasseyHyungki KimKatherine D KrauseW Russ AlgarPublished in: Bioconjugate chemistry (2020)
The prerequisites for maximizing the advantageous optical properties of colloidal semiconductor quantum dots (QDs) in biological applications are effective surface functionalization and bioconjugation strategies. Functionalization with dextran has been highly successful with some nanoparticle materials, but has had very limited application with QDs. Here, we report the preparation, characterization, and proof-of-concept applications of dextran-functionalized QDs. Multiple approaches to dextran ligands were evaluated, including performance with respect to colloidal stability across a range of pH, nonspecific binding with proteins and cells, and microinjection into cells and viability assays. Multiple bioconjugation strategies were demonstrated and applied, including covalent coupling to develop a simple pH sensor, binding of polyhistidine-tagged peptides to the QD for energy transfer-based proteolytic activity assays, and binding with tetrameric antibody complexes (TACs) to enable a sandwich immunoassay and cell immunolabeling and imaging. Our results show that dextran ligands are highly promising for the functionalization of QDs, and that the design of the ligands is tailorable to help optimally meet the requirements of applications.
Keyphrases
- quantum dots
- energy transfer
- induced apoptosis
- cell cycle arrest
- high resolution
- sensitive detection
- room temperature
- high throughput
- dna binding
- binding protein
- molecularly imprinted
- oxidative stress
- single cell
- cell therapy
- mesenchymal stem cells
- cell proliferation
- photodynamic therapy
- fluorescence imaging
- amino acid
- tandem mass spectrometry