Matrix-assisted laser desorption/Ionization coupled to Fourier transform ion cyclotron resonance mass spectrometry: a method to characterize temoporpfin photoproducts

✍ Scribed by Marc Angotti; Benoît Maunit; Jean-François Muller; Lina Bezdetnaya; François Guillemin

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 117 KB
• Volume: 13
• Category: Article
• ISSN: 0951-4198
• DOI: 10.1002/(sici)1097-0231(19990415)13:7<597::aid-rcm528>3.0.co;2-a

✦ Synopsis

Temoporpfin (m-THPC) has been developed as a new photodynamic therapeutic agent and is currently under clinical trials for the treatment of malignant tumors. In the present study matrix-assisted laser desorption/ionization (MALDI) coupled with Fourier transform mass spectrometry has been applied for the analysis of the products of photochemical m-THPC oxidation in an ethanolic solution upon red laser-light irradiation (! 650 nm). MALDI mass spectrometric studies together with spectroscopic analysis have demonstrated the formation of an intermediate compound with a signal cluster at m/z 744, with main absorption bands at 418 and 620 nm. The evolution of the m/z 744 product, during dark storage, supports the free radical chain auto-oxidation reaction, yielding the addition of four oxygen atoms to the m-THPC molecule.