Subnanosecond single photon timing measurements using a pulsed diode-laser.

Area of Science:

• Biophysics
• Photochemistry
• Spectroscopy

Background:

• Time-correlated single photon counting (TCSPC) is a crucial technique for measuring fluorescence lifetimes.
• Traditional light sources for TCSPC, such as pulsed lasers or gas discharge systems, can be expensive and complex.
• There is a need for cost-effective and convenient alternatives for fluorescence lifetime measurements.

Purpose of the Study:

• To evaluate the suitability of a pulsed diode laser (Hamamatsu Photonics PLP-01, 660 nm) as an economical replacement for standard light sources in TCSPC.
• To demonstrate the application of this diode laser system for determining fluorescence lifetimes of various photobiologically relevant compounds.

Main Methods:

• Utilized a commercial time-correlated single photon counting instrument.
• Employed a pulsed diode laser (Hamamatsu Photonics PLP-01, 660 nm) as the excitation source.
• Measured fluorescence lifetimes of phytochrome, chlorophyll a, 1,1'-diethyl-4,4' carbocyanine iodide (DCI/cryptocyanin), 5,10,15,20-tetra(p-phenyl) porphyrin, and stentorin I.

Main Results:

• The pulsed diode laser provided a convenient and inexpensive method for fluorescence lifetime analysis.
• Successful measurements were obtained for a range of photobiologically significant molecules.
• The results demonstrate the feasibility of using this diode laser in TCSPC applications.

Conclusions:

• The pulsed diode laser serves as a cost-effective and practical alternative to conventional light sources for TCSPC.
• This approach facilitates the study of fluorescence lifetimes in photobiology and related fields.
• The system's affordability and ease of use make advanced spectroscopic techniques more accessible.