Optical sensors based on hybrid aptamer/conjugated polymer complexes.

Area of Science:

• Biophotonics
• Molecular Biology
• Analytical Chemistry

Background:

• Single-stranded DNA aptamers exhibit specific binding to targets like potassium ions and human alpha-thrombin.
• Target binding induces a conformational change in the aptamer from an unfolded to a folded state.

Purpose of the Study:

• To develop a novel, label-free method for detecting human alpha-thrombin.
• To transduce aptamer conformational changes into an optical signal for sensitive detection.

Main Methods:

• Utilized single-stranded DNA aptamers for specific target recognition.
• Employed a water-soluble, cationic polythiophene derivative to detect aptamer conformational transitions.
• Transduced binding events into colorimetric or fluorometric signals.

Main Results:

• Achieved label-free detection of human alpha-thrombin.
• Demonstrated femtomole-level sensitivity for thrombin detection.
• Established a simple and rapid methodology for biophysical detection.

Conclusions:

• The developed biophotonic tool enables sensitive, label-free detection of human thrombin.
• This methodology is adaptable for detecting other proteins.
• The technique is suitable for high-throughput screening in drug discovery.