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Updated: Aug 19, 2026

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Characterization of photoproducts of m-THPP in aqueous solution
Natacha Lourette1, Benoît Maunit, Lina Bezdetnaya
1Laboratoire de Spectrométrie de Masse et de Chimie Laser (LSMCL), Université Paul Verlaine-Metz, Institut de Physique et d'Electronique de Metz (IPEM), Metz, France.
Abstract:
This study examined the nature of photoproducts after pulse laser irradiation (647.5 nm) of 5,10,15,20-tetrakis(meso-hydroxyphenyl)porphyrin (m-THPP) (10 micromol/L) in ethanol-water (1/99, vol/vol) solution. Spectroscopic measurements (UV-visible absorption and fluorescence) and mass spectrometry techniques (matrix-assisted laser desorption-ionization [MALDI] coupled with time-of-flight mass spectrometer [TOF-MS] or tandem time of flight mass spectrometer [TOF/TOF-MS]) were used to follow photomodifications. Spectroscopic measurements evidenced photomodification as the main process after m-THPP irradiation. Three oxidized photoproducts at m/z 693.25, 695.24 and 713.25 were characterized by MS. After prolonged irradiation new isotopic distributions were registered at m/z 1355.41, 2031.57, 2707.80 and 3383.98 with MALDI-TOF-MS and TOF/TOF-MS. These new photoproducts were attributed to covalent oligomeric structures as dimer, trimer, tetramer and pentamer of m-THPP.
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