Mewis, Ryan E., Savoie, Huguette, Archibald, Stephen J., Boyle, Ross W., "Synthesis and phototoxicity of polyethylene glycol (PEG) substituted metal-free and metallo-porphyrins: Effect of PEG chain length, coordinated metal, and axial ligand", PHOTODIAGNOSIS AND PHOTODYNAMIC THERAPY, 2009