Controlling the reactivity of ampiphilic quantum dots in biological assays through hydrophobic assembly of custom PEG derivatives.
Modifications of the quantum dot (QD) surface are routinely performed via covalent biomolecule attachment, and poly(ethylene glycol) (PEG) derivatization has previously been shown to limit nonspecific cellular interactions of QD probes. Attempts to functionalize ampiphilic QDs (AMP-QDs) with custom PEG derivatives having a hydrophobic terminus resulted in self-assembly of these PEG ligands to the AMP-QD surface in the absence of covalent coupling reagents. We demonstrate, via electrophoretic characterization techniques, that these self-assembled PEG-QDs exhibit improved passivation in biological environments and are less susceptible to unwanted protein adsorption to the QD surface. We highlight the artifactual fluorescent response protein adsorption can cause in biological assays, and discuss considerations for improved small molecule presentation to facilitate specific QD interactions.
Department of Chemistry, Vanderbilt University, Station B, 351822, Nashville, Tennessee, 37235-1822, USA.
Michael R
MR
Warnement
Ian D
ID
Tomlinson
Jerry C
JC
Chang
Michael A
MA
Schreuder
Courtney M
CM
Luckabaugh
Sandra J
SJ
Rosenthal
D000327:Adsorption; D000818:Animals; D016477:Artifacts; D001681:Biological Assay / Q000379:methods*; D002417:Cattle; D002460:Cell Line; D004591:Electrophoresis, Polyacrylamide Gel; D011992:Endosomes / Q000378:metabolism; D057927:Hydrophobic and Hydrophilic Interactions; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D008856:Microscopy, Fluorescence; D011092:Polyethylene Glycols / Q000737:chemistry*; D045663:Quantum Dots; D012710:Serum Albumin, Bovine / Q000737:chemistry / Q000378:metabolism; D013499:Surface Properties
D008024:Ligands; D012710:Serum Albumin, Bovine; D011092:Polyethylene Glycols