Surface-immobilized self-assembled protein-based quantum dot nanoassemblies.
Luminescent semiconductor quantum dot (QD)-based optical biosensors have the potential to overcome many of the limitations associated with using conventional organic dyes for biodetection. We have previously demonstrated a hybrid QD-protein-based fluorescence resonance energy transfer (FRET) sensor. Although the QD acted as an energy donor and a protein scaffold in the sensor, recognition and specificity were derived from the proteins. Transitioning this hybrid prototype sensor into flow cells and integrated devices will require a surface-immobilization strategy that allows the QD-based sensor to sample the environment and still maintain a distinct protein-covered QD architecture. We demonstrate a self-assembled strategy designed to accomplish this. Using glass slides coated with a monolayer of neutravidin (NA) as the template, QDs with maltose binding protein (MBP) and avidin coordinated to their surface were attached to the glass slides in discrete patterns using an intermediary bridge of biotinylated MBP or antibody linkers. Control of the surface location and concentration of the QD-protein-based structures is demonstrated. The utility of this self-assembly strategy is further demonstrated by assembling a QD-protein structure that allows the QDs to engage in FRET with a dye located on the surface-covering protein.
Center for Bio/Molecular Science and Engineering, Code 6900, Naval Research Laboratory, Washington, D.C. 20375, USA.
Kim E
KE
Sapsford
Igor L
IL
Medintz
Joel P
JP
Golden
Jeffery R
JR
Deschamps
Harry Tetsuo
HT
Uyeda
Hedi
H
Mattoussi
D001360:Avidin / Q000737:chemistry; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D019921:Biotinylation; D002352:Carrier Proteins / Q000737:chemistry; D031541:Fluorescence Resonance Energy Transfer / Q000295:instrumentation / Q000379:methods*; D058619:Maltose-Binding Proteins; D008565:Membrane Proteins / Q000737:chemistry*; D036103:Nanotechnology; D045663:Quantum Dots; D012680:Sensitivity and Specificity
D002352:Carrier Proteins; D058619:Maltose-Binding Proteins; D008565:Membrane Proteins; C093483:neutravidin; D001360:Avidin