Application of ESR Spectroscopy in the Study of the Light Efficiency of a Dental Translucent Fiberglass Post to Promote Polymerization

Simple and effective in situ sample illumination for electron paramagnetic resonance

“…Ex situ illumination is easy to achieve, and many different light sources, including light emitting diodes (LEDs) 1,2 and lasers, 3 have been reported. However, this method prohibits acquisition of the EPR spectrum during irradiation and can only measure changes that persist on a timescale longer than the time taken to place the sample in the spectrometer and record the measurement.…”

“…Many chemical reactions and processes have mechanisms involving species with unpaired electrons, either as reactants, products, intermediates or catalysts. These are measurable by electron paramagnetic resonance (EPR), and examples include organic radicals, 1,2 nitroxides, 3 metal centres/clusters, 4 and excited triplet states. The processes involving the generation or removal of these species may be initiated by light.…”

“…The processes involving the generation or removal of these species may be initiated by light. Common examples include the study of polymerisation, 1 photosensitisation for the generation of singlet oxygen, 3 catalytic, 2 or biocatalytic processes. To measure the changes in EPR active species caused by illumination, the sample can be irradiated ex situ , then inserted into the spectrometer and a spectrum recorded.…”