Teeuwen, P.C.P.; Melissari, Z.; Senge, M.O.; Williams, R.M. Metal Coordination Effects on the Photophysics of Dipyrrinato Photosensitizers. Molecules2022, 27, 6967.
Teeuwen, P.C.P.; Melissari, Z.; Senge, M.O.; Williams, R.M. Metal Coordination Effects on the Photophysics of Dipyrrinato Photosensitizers. Molecules 2022, 27, 6967.
Teeuwen, P.C.P.; Melissari, Z.; Senge, M.O.; Williams, R.M. Metal Coordination Effects on the Photophysics of Dipyrrinato Photosensitizers. Molecules2022, 27, 6967.
Teeuwen, P.C.P.; Melissari, Z.; Senge, M.O.; Williams, R.M. Metal Coordination Effects on the Photophysics of Dipyrrinato Photosensitizers. Molecules 2022, 27, 6967.
Abstract
Within this work we review the metal coordination effect on the photophysics of metal dipyrrinato complexes. Dipyrrinato complexes are promising candidates in the search for alternative transition metal photosensitizers for application in photodynamic therapy (PDT). These complexes can be activated by irradiation with light of a specific wavelength, after which cytotoxic reactive oxygen species (ROS) are generated. The metal coordination allows for the use of the heavy atom effect, which can enhance the triplet generation necessary for generation of ROS. Additionally, the flexibility of these complexes for metal ions, substitutions and ligands allows the possibility to tune their photophysical properties. A general overview of the mechanism of photodynamic therapy and the properties of the triplet photosensitizers is given, followed by further details of dipyrrinato complexes described in the literature that show relevance as photosensitizers for PDT. In particular, the photophysical properties of Re(I), Ru(II), Ir(III), Ni(II), Cu(II), Pd(II), Pt(II), Zn(II), Ga(III), In(III), Al(III), Sn(II), and P dipyrrinato complexes are discussed. The potential for future development in the field of (dipyrrinato)metal complexes is addressed and several new research topics are suggested throughout this work. We propose that significant advances could be made for heteroleptic bis(dipyrrinato)zinc(II) and homoleptic bis(dipyrrinato)palladium(II) complexes and their application as photosensitizers for PDT.
Keywords
Photochemistry; Photophysics; Coordination Chemistry; Metal atom effect; Photodynamic Therapy; Triplet Photosensitizer; Dipyrrinato Complexes; Singlet Oxygen Generation; Triplet-triplet Annihilation; Heavy atom effect.
Subject
Chemistry and Materials Science, Inorganic and Nuclear Chemistry
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
