Facile Strategy to Output Fluorescein from Nucleic Acid Interactions

Area of Science:

• Biochemistry
• Molecular Biology
• Chemical Biology

Background:

• Biomolecular operations are crucial for converting molecular signals into functional outputs, forming the basis for diagnostic and therapeutic systems.
• Developing novel outputs and facile chemical transformation methods is essential to enhance the functionality and applicability of biomolecular operations.

Purpose of the Study:

• To present a straightforward method for converting nucleic acid signals into versatile fluorescein outputs.
• To enable nucleic acid-initiated activation of fluorescein functionalities for bioanalytical applications.

Main Methods:

• A DNA-templated reaction utilizing riboflavin-photocatalyzed oxidation of dihydrofluorescein.
• Dihydrofluorescein preparation via simple sodium borohydride (NaBH4) reduction of fluorescein, avoiding complex chemical caging.

Main Results:

• The DNA-templated photooxidation demonstrated high efficiency with an apparent rate constant (kapp) of 2.7 × 10^-3/s.
• A clear fluorescein output signal was generated with low background due to the stability of dihydrofluorescein.
• Activated fluorescein functionalities included fluorescence and artificial oxidase activity.

Conclusions:

• The facile and efficient method allows for nucleic acid-initiated activation of fluorescein functions.
• This approach facilitates the design of novel bioanalytical systems, such as fluorescent and colorimetric DNA sensors.
• The presented biomolecular operation expands the scope of biomolecular circuit systems for diagnostic and therapeutic applications.