Visible to near IR luminescence spectrum of Radachlorin under excitation at 405nm

Highlights: • Luminescence spectrum of Radachlorin in water at 600–1350 nm. • Evaluation of relative contributions to the spectrum from different sources. • Ratio of the singlet oxygen signal to the total signal intensity. • Isolation of the singlet oxygen signal from the total signal at 1274 nm. The luminescence spectrum of Radachlorin dissolved in water in the 600–1350 nm spectral range excited by 405 nm light has been recorded at the first time. The spectrum contains a wide band with peaks centered at 662, 715, 940, and 1274 nm. Relative contributions to the spectrum from different sources have been evaluated. Ratio of the singlet oxygen signal to the total signal intensity averaged over the 1240–1300 nm spectral range was determined to be 40%. Isolation of the singlet oxygen signal from the total signal at 1274 nm has been achieved by means of a spectral-resolved TCSPC detection technique.