Nanodomain-Enhanced Stable and Multifunctional Probes with Near 100% Quantum Yield for Versatile Biosensing

Area of Science:

• Materials Science
• Biomedical Engineering
• Analytical Chemistry

Background:

• High quantum yield, stable, and multifunctional fluorescent probes are crucial for biomedicine and photoelectric sensing.
• Triphenylamine-based D-π-A fluorescent molecules offer potential for advanced probe development.

Purpose of the Study:

• To design and prepare a novel triphenylamine-based fluorescent molecule (TPA-CN) and encapsulate it within nanospheres for enhanced performance.
• To develop a dual-signal readout biosensor for ultrasensitive and instrument-free determination of target molecules, using chloramphenicol as a model.
• To evaluate the performance of the developed biosensor in terms of sensitivity, speed, and comparison to existing methods like enzyme-linked immunosorbent assays (ELISA).

Main Methods:

• Synthesis and characterization of a triphenylamine-based D-π-A fluorescent molecule (TPA-CN).
• Encapsulation of TPA-CN within polystyrene nanospheres to create intra-nanosphere confining domains, forming nanodomain-enhanced fluorescent nanospheres.
• Development of a dual-signal readout biosensor utilizing antigen-antibody specificity and bioenzyme catalytic activity for target detection.
• Performance evaluation including fluorescence quantum yield measurements, detection limit determination, and comparison with ELISA.

Main Results:

• The synthesized TPA-CN molecule exhibited a high fluorescence quantum yield of 88.84%.
• The nanodomain-enhanced fluorescent nanospheres achieved a significantly higher fluorescence quantum yield of 98.21%.
• The developed biosensor demonstrated an ultrasensitive detection limit of 24 pg/mL for chloramphenicol within 30 minutes in fluorescence mode, outperforming ELISA by 38-fold in sensitivity and 10-fold in speed.

Conclusions:

• The nanodomain-enhanced fluorescent probes offer superior fluorescence properties and stability.
• The developed dynamic biosensor provides a robust, versatile, and instrument-free platform for ultrasensitive detection.
• This technology holds significant promise for applications in public health and environmental monitoring.