ac9611733_si_001.pdf (329.96 kB)
Mechanism and Analytical Applicability of Luminol-Specific Extrinsic Lyoluminescence of UV-Irradiated Potassium Peroxodisulfate
journal contribution
posted on 1997-08-15, 00:00 authored by Cristina Mãtãchescu, Sakari Kulmala, Timo Ala-Kleme, Heikki JoelaLuminol shows strong chemiluminescence with an emission maximum at ∼430 nm in the presence of sulfate
radicals. Sulfate radicals were produced by the
dissolution of UV-irradiated potassium peroxodisulfate powder
in aqueous luminol solutions. The UV irradiation at
6.7
eV produces a solid solution of sulfate radical in potassium peroxodisulfate by rupturing −O−O− bonds, as in
solution, but now the solid solution is stable in a time
scale of years in dryness. In the present system,
luminol
chemiluminescence is produced via several parallel pathways having a common triggering step, one-electron
oxidation of luminol monoanion by sulfate or hydroxyl
radical. Present chemiluminescence allows sensitive
luminol detection from picomolar to micromolar level with
a linear response over 5 orders of magnitude, after which
luminescence is too strong for single-photon counting.
The
high sensitivity of luminol detection allows us to propose
extrinsic lyoluminescence of potassium peroxodisulfate
as a new and simple method for detection step of bioaffinity assays using luminol or isoluminol derivatives as
label compounds.