A Dendrimer-Based Time-Gated Concentric FRET Configuration for Multiplexed Sensing

Area of Science:

• Biochemistry
• Materials Science
• Nanotechnology

Background:

• Förster resonance energy transfer (FRET) is crucial for developing biological probes and sensors.
• Multiplexed detection traditionally uses multiple discrete donor-acceptor FRET probes.
• Concentric FRET (cFRET) probes allow multiplexed sensing using a single vector, but have been limited to semiconductor quantum dots.

Purpose of the Study:

• To demonstrate dendrimers labeled with a luminescent terbium complex (Tb) as a viable platform for cFRET probes.
• To establish a network of competitive and sequential FRET pathways using functionalized dendrimers.
• To develop a time-gated multiplexed assay for DNA targets using the dendrimer-based cFRET probes.

Main Methods:

• Functionalization of polyamidoamine dendrimers with Tb, biotin, NeutrAvidin, and dye-labeled oligonucleotide probes.
• Characterization of the synthesized probes' physical and photophysical properties.
• Development and demonstration of a time-gated multiplexed DNA detection assay.

Main Results:

• Successfully created dendrimer-based cFRET probes with Tb complexes.
• Established multiple Tb-to-dye and dye-to-dye FRET pathways within a single dendrimer structure.
• Demonstrated effective multiplexed DNA detection with background autofluorescence rejection using time-gating.

Conclusions:

• Dendrimer-based Tb complexes provide an advantageous alternative platform for cFRET probes.
• The developed dendrimer architecture validates cFRET as a general concept for biological sensing.
• This work represents a significant step towards a new generation of advanced biological sensing probes.