Multispectral fluorescence lifetime imaging device with a silicon avalanche photodetector

Area of Science:

• Optoelectronics
• Spectroscopy
• Biomedical instrumentation

Background:

• Traditional fluorescence lifetime measurement devices often use microchannel-plate photomultiplier tubes.
• These existing systems can suffer from variability, limited dynamic range, and slower acquisition speeds.
• There is a need for improved instrumentation for precise fluorescence lifetime analysis.

Purpose of the Study:

• To design, develop, and characterize a novel multi-spectral fluorescence lifetime measurement device.
• To leverage solid-state detectors and automated gain control for enhanced performance.
• To demonstrate the device's accuracy and advantages over existing technologies.

Main Methods:

• Incorporation of UV-enhanced avalanche photodetectors and high-speed analog-to-digital converters (2.5 GS/s).
• Implementation of channel-wise dynamic range adjustment (<2 ms) for signal-to-noise optimization.
• Characterization using fluorophores with known lifetimes (0.5-6.0 ns).

Main Results:

• Simultaneous recording of complete fluorescence decay across multiple spectral channels within microseconds.
• Demonstrated a 5-fold reduction in lifetime measurement variability under identical conditions.
• Achieved a 4-times faster imaging speed compared to microchannel-plate photomultiplier tube devices.

Conclusions:

• The novel device offers significant improvements in accuracy, speed, and measurement consistency.
• Solid-state detectors enable independent gain adjustment per spectral band, enhancing flexibility.
• The developed instrument paves the way for future miniaturization and performance enhancements in fluorescence lifetime imaging.