A versatile fiber-optic coupled system for sensitive optical spectroscopy in strong ambient light

Area of Science:

• Optical Spectroscopy
• Photochemistry
• Biophysics

Background:

• Spectroscopic studies are often hindered by strong ambient light.
• Accurate monitoring of light-sensitive biological molecules requires specialized optical systems.
• Understanding photodeterioration is crucial for food preservation and biological sample stability.

Purpose of the Study:

• To design and validate a fiber-optic optical system for spectroscopic analysis under intense ambient light.
• To simultaneously monitor absorption, emission, and picosecond-resolved fluorescence transients.
• To investigate the photodeterioration kinetics of vitamin B2 under UV light.

Main Methods:

• Development of a fiber-optic based optical system utilizing confocal geometry for stray-light rejection.
• Simultaneous measurement of absorption, emission, and picosecond-resolved fluorescence transients.
• Utilizing an ultrasensitive microchannel plate photomultiplier tube detector for low signal detection.
• Testing the system on vitamin B2 under strong UV light exposure.

Main Results:

• The system achieved efficient stray-light rejection, enabling measurements in strong ambient light.
• Picosecond-resolved fluorescence transients of vitamin B2 were reliably detected.
• The measured kinetics of vitamin B2 photodeterioration were consistent with existing literature.
• The system demonstrated the ability to monitor low optical signals from liquid samples under UV exposure.

Conclusions:

• The developed fiber-optic optical system is effective for spectroscopic studies in high ambient light conditions.
• The system reliably detects low optical signals, crucial for studying transient phenomena like fluorescence.
• The study provides insights into vitamin B2 photodeterioration and supports tungsten light for food preservation.