When molecular probes meet self-assembly: an enhanced quenching effect

Area of Science:

• Biochemistry
• Molecular Biology
• Nanotechnology

Background:

• Conventional quenched fluorescent probes often suffer from high background fluorescence, limiting their sensitivity.
• Existing probes may have suboptimal enzyme recognition properties due to quenching mechanisms.

Purpose of the Study:

• To investigate the effect of incorporating phenylalanine (F) or 4-fluoro phenylalanine ((f)F) on fluorescence probe background intensity.
• To develop a self-assembled nanoprobe strategy for enhanced fluorescence detection.
• To evaluate the performance of the developed nanoprobe for cell apoptosis detection.

Main Methods:

• Incorporation of one or two amino acids (F or (f)F) into quenched fluorescent probes.
• Utilizing molecular self-assembly to create nanoprobes.
• Assessing enzyme recognition properties of modified probes.
• Evaluating nanoprobe performance in cellular apoptosis detection assays.

Main Results:

• Incorporation of F or (f)F significantly lowered background fluorescence intensities.
• The enhanced quenching resulted from a synergistic effect of aggregation-caused quenching and the quencher.
• Enzyme recognition properties of the probes were largely unaffected.
• Self-assembled nanoprobes demonstrated superior performance in cellular apoptosis detection compared to unassembled probes.

Conclusions:

• Molecular self-assembly is an effective strategy to optimize and improve molecular probe performance.
• The developed strategy significantly boosts signal-to-noise ratios of fluorescence probes.
• This approach offers a simple yet powerful method for enhancing fluorescence-based detection systems.