Graphene oxide based fluorescent aptasensor for adenosine deaminase detection using adenosine as the substrate

Area of Science:

• Biochemistry
• Materials Science
• Analytical Chemistry

Background:

• Adenosine deaminase (ADA) plays a crucial role in immune function and is implicated in various diseases.
• Accurate and sensitive detection of ADA activity is essential for disease diagnosis and drug development.
• Existing methods for ADA detection can be complex and lack sensitivity.

Purpose of the Study:

• To develop a novel, highly sensitive, and selective fluorescent aptasensor for detecting adenosine deaminase (ADA) activity and inhibition.
• To utilize graphene oxide (GO) and an adenosine (AD)-specific aptamer for a cost-effective and simple sensing platform.
• To validate the sensor's performance in buffer and human serum samples and assess its potential for drug screening.

Main Methods:

• A fluorescent aptasensor was constructed using a dye-labeled AD-specific aptamer and graphene oxide (GO).
• The sensor leverages the fluorescence quenching effect of GO on the aptamer, which is recovered by AD.
• ADA activity is quantified by the fluorescence quenching resulting from ADA's conversion of AD to inosine, which has no aptamer affinity.

Main Results:

• The aptasensor demonstrated high sensitivity and selectivity for ADA activity detection with a low detection limit of 0.0129 U/mL.
• A strong linear correlation (R=0.9922) was observed when testing human serum samples with varying ADA concentrations.
• The sensor successfully investigated the inhibitory effects of erythro-9-(2-hydroxy-3-nonyl) adenine on ADA activity.

Conclusions:

• The developed GO-based fluorescence aptasensor provides a simple, cost-effective, and sensitive method for ADA activity and inhibitor detection.
• This platform shows significant potential for the diagnosis of ADA-related diseases and facilitates drug development.
• The aptasensor offers a promising tool for biochemical analysis and biomedical applications.