Fluorogenic resolution of ligand binding by a nucleic acid aptamer.

Area of Science:

• Biochemistry
• Analytical Chemistry
• Molecular Biology

Background:

• Nucleic acid aptamers are versatile molecules with specific binding capabilities.
• Developing sensitive and selective biosensors is crucial for various applications.
• Ligand-induced conformational changes in aptamers can be exploited for sensing.

Purpose of the Study:

• To create a solution-phase fluorescence-detected sensor using an ATP-binding aptamer.
• To utilize a 2'-amine group for a ligand-sensitive fluorogenic reaction.
• To demonstrate the sensor's functionality in detecting adenosine triphosphate (ATP).

Main Methods:

• Incorporation of a 2'-amine group into an ATP-binding aptamer.
• Reaction of the 2'-amine with fluorescamine to produce a fluorescent product.
• Detection of fluorescence via energy transfer to a tethered fluor (emitting at 615 nm).
• Monitoring fluorescence changes in the presence and absence of ATP.

Main Results:

• The modified aptamer produced a fluorescent signal upon reaction with fluorescamine.
• The presence of ATP significantly reduced the fluorogenic reaction.
• The sensor demonstrated functionality in both simplified conditions and a urine background.

Conclusions:

• Fluorogenic chemistry provides a general strategy for developing aptamer-based sensors.
• The developed sensor is sensitive to ATP through ligand-induced conformational changes.
• This approach offers a promising method for creating novel biosensors.