Real-time aptamer quantum dot fluorescent flow sensor

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Nanotechnology

Background:

• Developing sensitive and specific biosensors is crucial for both environmental monitoring and clinical diagnostics.
• Existing biosensing methods often face challenges with nonspecific binding and require complex sample preparation.
• Real-time detection capabilities are highly desirable for rapid identification of biological targets.

Purpose of the Study:

• To develop and validate a novel real-time biosensing platform.
• To create a portable and user-friendly aptamer-based fluorescent flow sensor prototype.
• To demonstrate the sensor's capability for specific analyte detection with minimal background noise.

Main Methods:

• Utilized a competitive displacement assay with surface-immobilized DNA aptamers and fluorescently labeled oligonucleotides.
• Employed quantum dots for bright and stable fluorescence, enabling prolonged detection in flow conditions.
• Tested the sensor prototype using an ATP-specific aptamer for quantifying ATP in a biological buffer.

Main Results:

• Successfully developed a working prototype of a real-time aptamer-based fluorescent flow sensor.
• Achieved specific detection of 0.1 mM ATP with a quantitative response range up to 5 mM.
• Demonstrated low nonspecific binding due to the competitive displacement mechanism.
• Confirmed the sensor's portability, ease of use, and potential for miniaturization and multiplexing.

Conclusions:

• The developed real-time aptamer-based fluorescent flow sensor is a promising tool for environmental and clinical pathogen monitoring.
• The competitive displacement strategy effectively minimizes nonspecific binding, enhancing detection specificity.
• The sensor's design facilitates adaptation for detecting a wide range of clinically and environmentally relevant targets.