A Low-Cost Time-Correlated Single Photon Counting Portable DNA Analyzer

Area of Science:

• Biophotonics
• Analytical Chemistry
• Molecular Diagnostics

Background:

• Photon-counting analysis is crucial for accurate, non-invasive nucleic acid diagnostics.
• Conventional instruments are bulky and expensive due to optics and electronics limitations.

Purpose of the Study:

• To develop a portable, low-cost time-correlated single photon-counting (TCSPC) system for DNA detection.
• To improve instrumentation for rapid, point-of-care nucleic acid diagnostics.

Main Methods:

• Designed optimized optical and electronic subsystems for effective emission filtering and size reduction.
• Utilized fluorescence lifetime measurements of a V-carbazole conjugated fluorophore bioassay for DNA detection verification.
• Developed a time-to-digital module with high timing resolution and low differential non-linearity.

Main Results:

• Achieved a timing resolution (FWHM) between 121–145 ps and DNL of -8.5% to +9.7%.
• Demonstrated a DNA detection limit of 6.25 nM and a dynamic range of 6.8 ns.
• Verified DNA detection and fluorescence lifetime extraction performance.

Conclusions:

• The proposed TCSPC system provides a portable and cost-effective solution for DNA diagnostics.
• This technology enables rapid, point-of-care nucleic acid analysis.
• The system offers good performance in DNA detection and fluorescence lifetime extraction.