Feasibility study on quantitative measurements of singlet oxygen generation using singlet oxygen sensor green

Area of Science:

• Photochemistry
• Chemical sensing
• Biomedical engineering

Background:

• Singlet oxygen ((1)O(2)) is a reactive oxygen species with significant biological implications.
• Accurate quantification of (1)O(2) generation is crucial for various applications, including photodynamic therapy.
• Existing methods for (1)O(2) detection may have limitations in direct quantitative measurement.

Purpose of the Study:

• To investigate the feasibility of using the Singlet Oxygen Sensor Green reagent (SOSG) for quantitative measurement of (1)O(2) generation.
• To establish a reliable protocol for quantifying (1)O(2) production using SOSG.

Main Methods:

• Utilized a newly developed (1)O(2)-specific fluorescence probe, SOSG.
• Monitored (1)O(2) generation from photoirradiation of Rose Bengal (RB) in phosphate-buffered saline (PBS).
• Performed kinetic analysis of the RB-sensitized photooxidation of SOSG to determine reaction rates.

Main Results:

• SOSG reacts with (1)O(2) to form fluorescent SOSG endoperoxides (SOSG-EP) with maximum emission at 531 nm.
• SOSG-EP fluorescence intensity correlates with RB and SOSG concentrations and photoirradiation time.
• Quantitative measurement of (1)O(2) generation was achieved by determining the reaction rate.
• (1)O(2) quantum yield of hematoporphyrin monomethyl ether (HMME) using SOSG agreed with direct luminescence measurements.

Conclusions:

• The SOSG reagent is a feasible tool for the quantitative measurement of (1)O(2) generation.
• Kinetic analysis of SOSG reaction rates allows direct and accurate quantification of (1)O(2) production.
• This method provides a reliable approach for studying (1)O(2) generation in various chemical and biological systems.