Platinum(II) Ring-Fused Chlorins as Near-Infrared Emitting Oxygen Sensors and Photodynamic Agents.
Novel near-infrared luminescent compounds based on platinum(II) 4,5,6,7-tetrahydropyrazolo[1,5-a]pyridine-fused chlorins are described. These compounds have high photostability and display light emission, in particular simultaneous fluorescence and phosphorescence emission in solution at room temperature, in the biologically relevant 700-850 nm red and near-infrared (NIR) spectral region, making them excellent materials for biological imaging. The simultaneous presence of fluorescence and phosphorescence emission at room temperature, with the phosphorescence strongly quenched by oxygen whereas fluorescence remains unaffected, allows these compounds to be used as ratiometric oxygen sensors in chemical and biological media. Both steady-state (fluorescence vs phosphorescence intensities) and dynamic (dependence of phosphorescence lifetimes upon oxygen concentration) luminescence approaches can be used. Photocytotoxicity studies against human melanocytic melanoma cells (A375) indicate that these compounds display potential as photosensitizers in photodynamic therapy.
CQC, Department of Chemistry, University of Coimbra , 3004-535 Coimbra, Portugal.
Nelson A M
NA
Pereira
Biophysics Unit, Faculty of Medicine of University of Coimbra, Azinhaga de Santa Comba, Celas, 3000-548 Coimbra, Portugal; CIMAGO-Center of Investigation in Environment, Genetics and Oncobiology, Faculty of Medicine of University of Coimbra, Azinhaga de Santa Comba, Celas, 3004-548 Coimbra, Portugal; CNC.IBILI Consortium, IBILI, University of Coimbra, Azinhaga de Santa Comba, Celas, 3004-548 Coimbra, Portugal.
Mafalda
M
Laranjo
Biophysics Unit, Faculty of Medicine of University of Coimbra, Azinhaga de Santa Comba, Celas, 3000-548 Coimbra, Portugal; CIMAGO-Center of Investigation in Environment, Genetics and Oncobiology, Faculty of Medicine of University of Coimbra, Azinhaga de Santa Comba, Celas, 3004-548 Coimbra, Portugal; CNC.IBILI Consortium, IBILI, University of Coimbra, Azinhaga de Santa Comba, Celas, 3004-548 Coimbra, Portugal.
João
J
Casalta-Lopes
Department of Chemical Engineering, CEMUC, University of Coimbra , Rua Silvio Lima Polo 2, 3030 290 Coimbra, Portugal.
Arménio C
AC
Serra
CQC, Department of Chemistry, University of Coimbra , 3004-535 Coimbra, Portugal.
Marta
M
Piñeiro
CQC, Department of Chemistry, University of Coimbra , 3004-535 Coimbra, Portugal.
João
J
Pina
CQC, Department of Chemistry, University of Coimbra , 3004-535 Coimbra, Portugal.
J Sérgio
JS
Seixas de Melo
School of Chemistry, SFI Tetrapyrrole Laboratory, Trinity Biomedical Sciences Institute, Trinity College Dublin, The University of Dublin , 152-160 Pearse Street, Dublin 2, Ireland.
Mathias O
MO
Senge
Biophysics Unit, Faculty of Medicine of University of Coimbra , Azinhaga de Santa Comba, Celas, 3000-548 Coimbra, Portugal.
M Filomena
MF
Botelho
CQC, Department of Chemistry, University of Coimbra, 3004-535 Coimbra, Portugal; Centro de Química-Física Molecular (CFQM), and the Institute of Nanoscience and Nanotechnology (IN), Instituto Superior Técnico, University of Lisbon, 1049-001 Lisbon, Portugal.
Liliana
L
Martelo
CQC, Department of Chemistry, University of Coimbra , 3004-535 Coimbra, Portugal.
Hugh D
HD
Burrows
CQC, Department of Chemistry, University of Coimbra , 3004-535 Coimbra, Portugal.
Teresa M V D
TM
Pinho E Melo
PDT; Pt(II) chlorins; oxygen sensing; photosensitizers; theranostics