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Updated: Jan 18, 2026
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Inactivation of Pathogens via Visible-Light Photolysis of Riboflavin-5′-Phosphate
Published on: April 6, 2022
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Riboflavin - understanding the dynamics and interactions of the triplet state
Marek Scholz1, Jan Moučka1, Jakub Pšenčík1
1Charles University, Faculty of Mathematics and Physics, Department of Chemical Physics and Optics, Prague, The Czech Republic. Roman.Dedic@matfyz.cuni.cz.
Physical Chemistry Chemical Physics : PCCP
|January 16, 2026
Summary
Riboflavin
Area of Science:
- Photochemistry
- Biochemistry
- Food Science
Background:
- Riboflavin is a vitamin and nutrient.
- It acts as a photosensitizer, generating singlet oxygen.
- Inconsistent literature data exists on riboflavin's triplet and singlet oxygen dynamics.
Purpose of the Study:
- To clarify riboflavin's triplet and singlet oxygen dynamics.
- To investigate quenching mechanisms involving riboflavin and sodium azide.
- To explore the role of delayed fluorescence (DF) in energy transfer.
Main Methods:
- Kinetic analysis of riboflavin in phosphate buffered water.
- Measurement of triplet and singlet oxygen lifetimes.
- Quenching studies with sodium azide and other photosensitizers.
Main Results:
- Riboflavin exhibits unusually close triplet (3.2 µs) and singlet oxygen (3.7 µs) lifetimes.
- Sodium azide efficiently quenches riboflavin triplets, not singlet oxygen.
- Riboflavin's quenching of singlet oxygen is negligible.
- Pronounced delayed fluorescence (DF) was observed, linked to singlet oxygen feedback.
- Triplet-triplet energy transfer is dominant for aluminum phthalocyanine.
Conclusions:
- Precise kinetic analysis is crucial for understanding riboflavin's photophysics.
- Sodium azide's quenching behavior differs significantly between riboflavin triplets and singlet oxygen.
- Delayed fluorescence provides insights into energy transfer mechanisms involving riboflavin.
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