Adenine-based small molecule fluorescent probe for imaging mitochondrial nucleic acid

Area of Science:

• Chemical Biology
• Molecular Biology
• Cell Biology

Background:

• Nucleic acid detection is crucial for understanding cellular processes.
• Developing selective and sensitive fluorescent probes is essential for biological imaging.
• Existing probes may lack specificity or exhibit weak fluorescence responses.

Purpose of the Study:

• To design and synthesize a novel small molecule fluorescent probe (probe 1) for nucleic acid detection.
• To investigate the photophysical properties and selectivity of probe 1 towards DNA and RNA.
• To evaluate the probe's ability to image nucleic acids in live cells, specifically in mitochondria and nucleoli.

Main Methods:

• Synthesis of an adenine-coumarin derivative as probe 1.
• Spectroscopic analysis to determine fluorescence enhancement and quantum yield changes upon nucleic acid binding.
• Quantitative analysis to establish linear relationships between fluorescence intensity and nucleic acid concentration.
• Cellular imaging experiments using HeLa cells, including co-staining and nucleic acid digestion assays.

Main Results:

• Probe 1 demonstrated significant fluorescence enhancement upon binding to both DNA (5.68 times) and RNA (9.73 times).
• Fluorescence quantum yield increased from 2.5% to 11.7% for DNA and 22.5% for RNA.
• An excellent linear correlation was observed between fluorescence intensity and nucleic acid concentrations.
• Probe 1 selectively imaged nucleic acids within mitochondria and nucleoli in HeLa cells.

Conclusions:

• The developed adenine-coumarin based probe 1 is a sensitive and selective tool for detecting DNA and RNA.
• Probe 1 exhibits favorable photophysical properties, including significant fluorescence enhancement and quantum yield increase.
• The probe's ability to selectively image nucleic acids in specific cellular organelles highlights its potential for biological research.