title: Photochemistry and Cytotoxicity Evaluation of Heptamethinecyanine Near Infrared (NIR) Dyes.
abstract: The present study investigates the photochemical properties of potential photosensitizers for photodynamic therapy, namely four commercial heptamethinecyanine dyes (IR125, IR780, IR813, IR820). Spectroscopic studies were made by means of laser induced fluorescence and laser flash photolysis in order to obtain fluorescence quantum yields and transient absorption spectra. Fluorescence lifetimes were also determined. The differences encountered were essentially related with the interaction of the sulfonate groups with the solvent, and also regarding the rigidification of the central bridge connecting the two nitrogen-containing heterocyclic groups. Transient absorption studies were performed both in aerated and oxygen free samples, to conclude about the formation of photoisomers and triplet state. For the four dyes under study, a cytotoxic evaluation in the dark and after irradiation was performed using HeLa cells as the model cell line, which revealed significant changes after irradiation mainly in IR125 and IR813 dyes. Confocal microscopy analysis showed that these dyes tend to enter to the intracellular space.
authors.affiliation: Molecular Physical Chemistry Center, and IN-Institute of Nanoscience and Nanotechnology, Instituto Superior Técnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisboa, Portugal. luisfilipevf@ist.utl.pt.
authors.forename: David S
authors.initials: DS
authors.lastname: Conceição
authors.forename: Diana P
authors.initials: DP
authors.lastname: Ferreira
authors.forename: Luís F Vieira
authors.initials: LF
authors.lastname: Ferreira
mesh_terms: D002470:Cell Survival / Q000187:drug effects; D004396:Coloring Agents / Q000737:chemistry* / Q000494:pharmacology; D006367:HeLa Cells; D006801:Humans; D007211:Indoles / Q000737:chemistry / Q000494:pharmacology; D018613:Microscopy, Confocal; D010777:Photochemistry / Q000379:methods*; D017319:Photosensitizing Agents / Q000737:chemistry* / Q000494:pharmacology*
chemical_list: D004396:Coloring Agents; C472723:IR125; D007211:Indoles; D017319:Photosensitizing Agents
references.citation: Int J Biomed Imaging. 2012;2012:940585
references.pmid: 22577366
references.citation: Biochim Biophys Acta. 1992 Apr 13;1105(2):333-5
references.pmid: 1586670
references.citation: Curr Opin Biotechnol. 2007 Feb;18(1):17-25
references.pmid: 17234399
references.citation: J Pharm Sci. 2013 Jan;102(1):6-28
references.pmid: 23132644
references.citation: J Photochem Photobiol A Chem. 2008 Dec 15;200(2-3):438-444
references.pmid: 20016664
references.citation: J Photochem Photobiol B. 1988 May;1(4):437-46
references.pmid: 3149292
references.citation: ChemMedChem. 2008 Jul;3(7):1110-7
references.pmid: 18409176
references.citation: Curr Opin Chem Biol. 2010 Feb;14(1):64-70
references.pmid: 19926332
references.citation: J Photochem Photobiol B. 2002 Aug;68(1):15-22
references.pmid: 12208032
references.citation: Biomaterials. 2013 Mar;34(9):2244-51
references.pmid: 23261220
references.citation: J Photochem Photobiol B. 2006 Nov 1;85(2):150-4
references.pmid: 16857379
references.citation: Biomaterials. 2012 Mar;33(7):2230-9
references.pmid: 22182749
references.citation: Photochem Photobiol Sci. 2013 Jul;12(7):1187-92
references.pmid: 23584281
references.citation: Chem Rev. 2010 May 12;110(5):2709-28
references.pmid: 19831417
references.citation: Acad Radiol. 2002 Aug;9 Suppl 2:S320-2
references.pmid: 12188261
references.citation: Biol Pharm Bull. 1996 Nov;19(11):1518-20
references.pmid: 8951178
references.citation: Curr Drug Discov Technol. 2007 Dec;4(4):229-45
references.pmid: 18045086
references.citation: Bioorg Med Chem Lett. 2012 Jan 15;22(2):1242-6
references.pmid: 22177785
references.citation: Annu Int Conf IEEE Eng Med Biol Soc. 2009;2009:114-7
references.pmid: 19964923