Table 1 Transient-absorption lifetimes and quantum yields of singlet-oxygen generation.

From: Detection of the thietane precursor in the UVA formation of the DNA 6-4 photoadduct

DNA system

τ1 (ps)a

τ2 (ps)a

τ3 (ps)a

τ4 (ns)

ΦΔ (air)b

ΦΔ (O2)b

T(T4tT)2T2

0.26 ± 0.02

3 ± 2c

290 ± 70c

23a,d

0.02 ± 0.01

0.04 ± 0.01

4tT

0.24 ± 0.02

2 ± 1c

56 ± 8c

4200 ± 300e

0.17 ± 0.02

–

  1. aMeasured in PBS pH 7.4 following excitation at 342 nm with reported errors equal to twice the standard deviation of at least two separate measurements.
  2. bMeasured in deuterated TRIS buffer solutions at pH 7.4 following excitation at 355 nm.
  3. cτ2 and τ3 are correlated to each other, and the reported large errors take into consideration this correlation.
  4. dExtrapolated lifetime assuming a complete exponential decay to the ground state.
  5. eTriplet lifetime calculated at infinite dilution in acetonitrile42.
Back to article page