Real-time data acquisition incorporating high-speed software correlator for single-molecule spectroscopy

Area of Science:

• Spectroscopy and Detection
• Physical Chemistry
• Biophysics

Background:

• Single-molecule spectroscopy is vital for studying individual fluorescent particles and their environmental interactions.
• Current systems can be costly and complex, limiting accessibility.

Purpose of the Study:

• To develop and validate a low-cost, software-based system for simultaneous real-time data acquisition and analysis in single-molecule experiments.
• To optimize real-time autocorrelation calculations for typical single-molecule count rates.

Main Methods:

• A multi-core computer and a low-cost counting board were utilized for hardware.
• Software was developed in a parallel programming environment with ANSI-C for time-critical operations.
• A novel, efficient real-time autocorrelation algorithm (ACF) was implemented and optimized.

Main Results:

• The system successfully performed simultaneous real-time acquisition, storage, and analysis of fluorescence time traces, autocorrelation functions, and delay histograms.
• The autocorrelation algorithm demonstrated performance independent of temporal resolution at all time delays.
• Validation confirmed the system's accuracy by comparison with a commercial correlator.

Conclusions:

• The developed low-cost system provides a robust and efficient platform for single-molecule spectroscopy.
• The optimized real-time autocorrelation algorithm enhances data processing capabilities for typical experimental conditions.
• The system's performance was validated under realistic experimental conditions, demonstrating its practical utility.